A phase I radiation dose-escalation study to determine the maximal dose of radiotherapy in combination with weekly gemcitabine in patients with locally advanced pancreatic adenocarcinoma.

Abstract

The primary objective of this study was to determine the maximum tolerated dose (MTD) of escalating doses of radiotherapy (RT) concomitantly with a fixed dose of gemcitabine (300 mg/m2/week) within the same overall treatment time.
Thirteen patients were included. Gemcitabine 300 mg/m2/week was administered prior to RT. The initial dose of RT was 45 Gy in 1.8 Gy fractions, escalated by adding 5 fractions of 1.8 Gy (one/week) to a dose of 54 Gy with a total duration kept at 5 weeks. All patients received a dynamic MRI to assess the pancreatic respiratory related movements. Toxicity was scored using the RTOG-EORTC toxicity criteria.
Three of six patients experienced an acute dose limiting toxicity (DLT) at the 54 Gy dose level. For these patients a grade III gastro-intestinal toxicity (GI) was noted. Patients treated at the 45 Gy dose level tolerated therapy without DLT. The 54 Gy dose level was designated as the MTD and was deemed not suitable for further investigation. Between both dose levels, there was a significant difference in percentage weight loss (p = 0.006) and also in cumulative GI toxicity (p = 0.027). There was no grade 3 toxicity in the 45 Gy cohort versus 4 grade 3 toxicity events in the 54 Gy cohort. The mean dose to the duodenum was significantly higher in the 54 Gy cohort (38.45 Gy vs. 51.82 Gy; p = 0.001).
Accelerated dose escalation to a total dose of 54 Gy with 300 mg/m2/week gemcitabine was not feasible. GI toxicity was the DLT. Retrospectively, the dose escalation of 9 Gy by accelerated radiotherapy might have been to large. A dose of 45 Gy is recommended. Considering the good patient outcomes, there might be a role for the investigation of a fixed dose of gemcitabine and concurrent RT with small fractions (1.8 Gy/day) in borderline resectable or unresectable non-metastatic locally advanced pancreatic cancer.

Full text

Page 1

BioMed Central
Page 1 of 7
(page number not for citation purposes)
Radiation Oncology
Open Access
Research
A phase I radiation dose-escalation study to determine the maximal
dose of radiotherapy in combination with weekly gemcitabine in
patients with locally advanced pancreatic adenocarcinoma
Tom Budiharto1,6, Karin Haustermans*1,6, Eric Van Cutsem1,6, Werner Van
Steenbergen5,6, Baki Topal2,6, Raymond Aerts2,6, Nadine Ectors4,6,
Didier Bielen3,6, Dirk Vanbeckevoort3,6, Laurence Goethals1,6 and
Chris Verslype1,6
Address: 1Department of Radiotherapy, University Hospitals Leuven, Leuven, Belgium, 2Department of Abdominal Surgery, University Hospitals
Leuven, Leuven, Belgium, 3Department of Radiology, University Hospitals Leuven, Leuven, Belgium, 4Department of Pathology, University
Hospitals Leuven, Leuven, Belgium, 5Department of Gastroenterology, University Hospitals Leuven, Leuven, Belgium and 6Leuvens Kanker
Instituut, LKI, Leuven, Belgium
Email: Tom Budiharto - tom.budiharto@uz.kuleuven.ac.be; Karin Haustermans* - karin.haustermans@uz.kuleuven.ac.be; Eric Van
Cutsem - eric.vancutsem@uz.kuleuven.ac.be; Werner Van Steenbergen - werner.vansteenbergen@uz.kuleuven.ac.be;
Baki Topal - baki.topal@uz.kuleuven.ac.be; Raymond Aerts - raymond.aerts@uz.kuleuven.ac.be;
Nadine Ectors - nadine.ectors@uz.kuleuven.ac.be; Didier Bielen - didier.bielen@uz.kuleuven.ac.be;
Dirk Vanbeckevoort - dirk.vanbeckevoort@uz.kuleuven.ac.be; Laurence Goethals - laurence.goethals@uz.kuleuven.ac.be;
Chris Verslype - chris.verslype@uz.kuleuven.ac.be
* Corresponding author
Abstract
Background: The primary objective of this study was to determine the maximum tolerated dose (MTD) of escalating doses of
radiotherapy (RT) concomitantly with a fixed dose of gemcitabine (300 mg/m2/week) within the same overall treatment time.
Methods: Thirteen patients were included. Gemcitabine 300 mg/m2/week was administered prior to RT. The initial dose of RT
was 45 Gy in 1.8 Gy fractions, escalated by adding 5 fractions of 1.8 Gy (one/week) to a dose of 54 Gy with a total duration
kept at 5 weeks. All patients received a dynamic MRI to assess the pancreatic respiratory related movements. Toxicity was
scored using the RTOG-EORTC toxicity criteria.
Results: Three of six patients experienced an acute dose limiting toxicity (DLT) at the 54 Gy dose level. For these patients a
grade III gastro-intestinal toxicity (GI) was noted. Patients treated at the 45 Gy dose level tolerated therapy without DLT. The
54 Gy dose level was designated as the MTD and was deemed not suitable for further investigation.
Between both dose levels, there was a significant difference in percentage weight loss (p = 0.006) and also in cumulative GI
toxicity (p = 0.027). There was no grade 3 toxicity in the 45 Gy cohort versus 4 grade 3 toxicity events in the 54 Gy cohort.
The mean dose to the duodenum was significantly higher in the 54 Gy cohort (38.45 Gy vs. 51.82 Gy; p = 0.001).
Conclusion: Accelerated dose escalation to a total dose of 54 Gy with 300 mg/m2/week gemcitabine was not feasible. GI
toxicity was the DLT. Retrospectively, the dose escalation of 9 Gy by accelerated radiotherapy might have been to large. A dose
of 45 Gy is recommended. Considering the good patient outcomes, there might be a role for the investigation of a fixed dose
of gemcitabine and concurrent RT with small fractions (1.8 Gy/day) in borderline resectable or unresectable non-metastatic
locally advanced pancreatic cancer.
Published: 22 September 2008
Radiation Oncology 2008, 3:30 doi:10.1186/1748-717X-3-30
Received: 21 March 2008
Accepted: 22 September 2008
This article is available from: http://www.ro-journal.com/content/3/1/30
© 2008 Budiharto et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0),
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Page 2

Radiation Oncology 2008, 3:30http://www.ro-journal.com/content/3/1/30
Page 2 of 7
(page number not for citation purposes)
Background
Pancreatic ductal adenocarcinoma has a 5-year survival
rate of 0.4% [1] to 5% [2]. Because of this dismal progno-
sis, it is one of the top four causes of cancer death in the
Western world [3]. Surgical resection of the tumour is
associated with improved 5-year survival up to approxi-
mately 20% [4], but unfortunately, only 10% to 20% of
patients are candidate for surgery at initial diagnosis [5]
and there remains a high incidence of local tumour recur-
rence [6]. Approximately 40% of patients with pancreatic
cancer present with locally advanced non-metastatic dis-
ease. Tumour adherence or invasion into adjacent struc-
tures, particularly the celiac and superior mesenteric
vasculature (T3-4 or stage III disease according to the
TNM-classification) make complete resection difficult or
impossible. The median survival of patients with non-
metastatic locally advanced pancreatic cancer (LAPC) var-
ies between 6 to 12 months when treated with palliative
therapy.
Based on an early trial by the Gastrointestinal Tumour
Study Group, which demonstrated a modest survival ben-
efit with chemoradiotherapy (CRT) when compared to
radiation therapy (RT) or chemotherapy alone, patients
who have unresectable disease are often treated with con-
current fluorouracil (5-FU)-based CRT [7].
Gemcitabine has been shown to provide a survival advan-
tage over 5-FU in patients with locally advanced (unre-
sectable) or metastatic pancreatic cancer [8]. Also,
different in vitro and in vivo studies have demonstrated
that gemcitabine is a potent radiosensitizer in human can-
cer cell lines including pancreatic cancer cell lines [9-12].
Thus integration of gemcitabine with radiation in a CRT
protocol represents an alternative approach to improve
outcome in patients with pancreatic cancer [13].
Based on studies of hyperfractionation and/or accelera-
tion in squamous cell cancer of head and neck [14], one
could expect that the combination of RT dose escalation
and concurrent gemcitabine would also improve the rate
of loco-regional control and in the same time overall sur-
vival in patients with non-metastatic LAPC.
The primary objective of this study was to define the max-
imum tolerated dose (MTD) of escalating doses of RT
delivered concurrently with a fixed dose of gemcitabine
(300 mg/m2) administered on a weekly basis within the
same overall treatment time in patients with borderline
resectable or unresectable LAPC.
Methods
Eligibility
Eligibility criteria for study entry included cytological or
histological confirmation of pancreatic adenocarcinoma.
Patients were required to have T3-4 disease (Tumour
adherence or invasion into adjacent structures, particu-
larly the celiac and superior mesenteric vasculature), N0-
1 according to the TNM-classification, without distant
metastases (M0). Eligible patients were required to be ≥
18 years, to have a WHO performance status ≤ 2 and a life
expectancy of more than 3 months. Pre-treatment evalua-
tion included a complete history and physical examina-
tion, a diagnostic CT scan of the abdomen with
intravenous (IV) contrast, as well as a blood exam with an
adequate haematological (absolute neutrophil count
(ANC) ≥ 1.5 × 103/L, platelets > 100 × 103/L, hemoglobin
level > 10 g/dL), renal (serum creatinin concentration < 2
mg/dL) and liver function (bilirubin ≤ 1.5 times UNL,
SGOT and SGPT ≤ 2.5 times UNL). All patients underwent
an ERCP and also a laparoscopy to exclude peritoneal
metastasis. Patients were excluded for any other concom-
itant cancers or serious illnesses (medical or psychiatric)
and for metastatic disease. This phase I trial was approved
by an independent ethics committee and all patients gave
written informed consent before study enrolment.
Study design
The treatment schedule is shown in Figure 1. Gemcitabine
was administered weekly in a single dose of 300 mg/m2 as
a 30-min IV infusion at least one hour prior to RT. This
dose was chosen based on literature data [13,15,16] and
taking into account that escalating doses of RT would be
given. The starting dose of RT was 45 Gy in 25 fractions of
1.8 Gy per day. Dose escalation was achieved by giving 2
fractions of 1.8 Gy per day on a fixed day, with an inter-
fraction interval of at least 6 hours. The escalating dose
levels we planned to test were: 54 Gy, 59.4 Gy and 63 Gy.
The total duration of the RT was kept on 5 weeks. Five
patients were treated in the first dose cohort and followed
for one month post treatment before entering patients in
subsequent cohorts. We have chosen to escalate the dose
by adding an extra fraction of 1.8 Gy 6 to 8 hours after the
first one on some days instead of increasing the dose per
fraction as smaller fraction sizes induce less late side
effects. Moreover, adding extra fractions on some days did
not prolong overall treatment time. With this accelerated
scheme, we wanted to avoid to prolong the overall treat-
ment time as this may be deleterious (accelerated repopu-
lation) and as these patients have such a poor prognosis
that we did not want to jeopardise their limited survival
by increasing overall treatment time.
Radiotherapy
The dose was prescribed at the centre of the target area or
at the intersection of central rays of the beam. Highly con-
formal beams were used, with at least 5 incident beams
and 18 MV photons. CT-based treatment planning (with
a contrast enhanced CT scan using 5 mm slices) was
required for all patients as well as a dynamic MRI in treat-

Page 3

Radiation Oncology 2008, 3:30http://www.ro-journal.com/content/3/1/30
Page 3 of 7
(page number not for citation purposes)
ment position to assess the corrections needed for breath-
ing movement [17]. The clinical target volume (CTV)
included the primary tumour with the peripancreatic and
pathological lymph nodes. The patient specific margins
around the clinical target volume to account for breathing
motion as defined on dynamic MRI were then expanded
with another 1 cm to the planning target volume (PTV).
The supportive care program consisted of a close follow
up (at least weekly) by a medical doctor combined with a
regular consultation with the dietician and prescription of
an anti-emetic therapy (5-HT3 antagonist) whenever
required.
Toxicity criteria
Patients interrupted treatment in case of grade 4 adverse
events. When one of five patients experienced a dose lim-
iting toxicity (DLT) in a stratum, an additional 5 patients
were entered at that dose level. A DLT was defined as one
or more of the following events occurring within 8 weeks
after the start of treatment: any grade 3 gastro-intestinal
(GI) toxicity, any grade 3 liver toxicity that persisted for
more than 2 weeks, pancreatitis, any grade 4 skin toxicity
within the radiation field, an interruption of the course of
RT due to toxicity that lasted more than 2 consecutive
weeks, or if 2 interruptions occurred each of which lasted
at least one week, an interruption of the course of chemo-
therapy due to haematological toxicity for 2 consecutive
weeks (cycles), febrile neutropenia, or any other grade 3
or 4 toxicity. The RT doses were fixed; however, RT was
planned to be interrupted temporarily to manage local
toxicity presented in body areas in the radiation volumes,
especially in case of grade 3 or 4 adverse events involving
small and large intestine. If the toxicity reduced to grade 1
or 2, RT was continued. Based upon the blood counts on
the day of treatment, a 20% dose reduction of gemcitab-
ine was given for ANC > 1.0 × 103/L and < 1.499 × 103/L
and/or platelet count > 50 × 103/L and < 75 × 103/L. A
treatment was dropped for ANC > 0.5 × 103/L and < 0.999
× 103/L and/or platelet count > 20 × 103/L and < 50 ×
103/L. A new treatment cycle could begin when blood
counts were recuperated. When ANC was < 0.5 × 103/L
and/or platelet count < 20 × 103/L, the administration of
gemcitabine was stopped.
Patients were examined and toxicities were scored at least
every week until 4 weeks after the end of treatment. All
toxicities encountered during the course of CRT were eval-
uated using the RTOG-EORTC Common Toxicity Criteria.
The stratum in which DLT were seen, will be defined as
the MTD. The recommended dose of RT was defined as
one level below the MTD.
Treatment scheme: different RT dose levels to be investigated
Figure 1
Treatment scheme: different RT dose levels to be investigated. Radiotherapy dose escalation scheme investigated in
this phase I trial; gemcitabine (G) was administered on day 1 of week 1, 2, 3, 4 and 5 in a single dose of 300 mg/m2 as a 30-min
IV infusion at least one hour prior to RT; the starting dose of RT was 45 Gy in 25 fractions of 1.8 Gy per day (XRT); dose esca-
lation was achieved by giving 2 fractions of 1.8 Gy per day on a fixed day, with an interfraction interval of at least 6 hours, an
arrow indicates an extra fraction of 1.8 Gy on that day; the escalating dose levels tested were: 54 Gy, 59.4 Gy and 63 Gy; the
total duration of the RT was kept on 5 weeks.
Dose Week 1 Week 2 Week 3 Week 4 Week 5
M T W T F MT WT F MT W T F M T WT FM T W T F
45 Gy
1.8 Gy per fx

54 Gy
1.8 Gy per fx

59.4 Gy
1.8 Gy per fx


G


G


G


G


G


G


G


G


G


G


G


G


G


G


G


G


G


G


G


G

?

?
?
?
XRT XRTXRTXRT XRT

?

?
?
?
?
?

?

?

?
63 Gy
1.8 Gy per fx
?
?
?
?

?
?

?

???

Page 4

Radiation Oncology 2008, 3:30http://www.ro-journal.com/content/3/1/30
Page 4 of 7
(page number not for citation purposes)
Surgery
Approximately 4 to 6 weeks after the end of the CRT,
patients were re-evaluated with a CT of the abdomen to
assess resectability. When a patient had become operable,
he/she was referred for surgery. If a patient stayed inoper-
able, treatment with conventional systemic gemcitabine
was given until disease progression or until a total dura-
tion of 6 months. The followed scheme was 1000 mg/m2
per week for 3 consecutive weeks with one week of rest.
Statistical considerations
The study intent was to determinate the DLT of escalating
doses of RT delivered concurrently with a fixed dose of
gemcitabine (300 mg/m2) administered on a weekly basis
within the same overall treatment time. The different
parameters in both of the dose cohorts were compared by
a student's t-test. The relationship between the percentage
weight loss and the cumulative GI toxicity (= sum of all
different GI toxicities) and the total dose administered to
the different normal tissues was evaluated with a Spear-
man rank correlation test. A p-value ≤ 0.05 was considered
to be significant for these tests. Survival was measured
from the day of diagnosis until death or the last date of
follow up.
Results
Patient characteristics and treatment received
Over a 2 year period, 13 patients with locally advanced
histologically proven, T3-T4 or stage III pancreatic adeno-
carcinoma, were enrolled in this study. No patient had
received prior therapy for pancreatic cancer. The median
age of study participants was 58 years (range, 42–70
years). There were 7 men and 6 women. WHO perform-
ance status was 0 in 6, 1 in 5 and 2 in 2 subjects. The
median duration of RT was 37 days (range, 32–40 days).
The median volume of the PTV was 536.7 cm3 (mean of
522.5 cm3), ranging from 200.3 cm3 to 869.0 cm3. The
volume of each PTV is listed in Table 1 per patient.
Five patients were included in the 45 Gy cohort and they
completed the planned treatment without experiencing
any DLT. One patient in this cohort required a dose reduc-
tion of gemcitabine because of haematological toxicity,
but there was no delay in treatment delivery. The next
dose level was then tested and 5 patients were included in
the 54 Gy cohort. All patients were able to complete the
planned treatment, but one patient received only 4 cycles
of gemcitabine. Two of 5 patients experienced a DLT,
which consisted of acute grade 3 GI toxicity (grade 3 nau-
sea for the first patient and grade 3 nausea and vomiting
for the second). An additional 5 patients were planned to
enter this dose level, but the first patient also suffered a
grade 3 GI toxicity (nausea), so dose escalation was inter-
rupted and the 54 Gy dose level was designated as the
MTD and was deemed not suitable for further investiga-
tion. Another 2 patients were then studied at the dose
level below (45 Gy).
Toxicity
All 13 patients were evaluable for toxicity analysis, with
the different GI toxicities experienced per dose cohort dur-
ing CRT shown in Table 2. Although it was not the intent
of the study to perform a formal comparison between the
two dose cohorts (due to the limited number of patients
and the non-randomised setting), we report here differ-
ences and correlations that might be of interest. Between
both dose levels, there was a significant difference in per-
centage weight loss (4.51% ± 2.11 in the 45 Gy cohort and
11.88% ± 5.26 in the 54 Gy cohort; p = 0.006) and also in
cumulative GI toxicity (p = 0.027). There was no grade 3
toxicity in the 45 Gy cohort versus 4 grade 3 toxicity events
in the 54 Gy cohort. There was no significant difference in
the mean dose to the stomach between both dose levels
but the mean dose to the duodenum was significantly
higher in the 54 Gy cohort (38.45 Gy vs. 51.82 Gy; p =
0.001).
Non-resected patients
Eight of the 13 patients did not undergo resection. For
three of these patients, a palliative Roux-en-Y choledocho-
jejunostomy and gastrojejunostomy were performed pre-
CRT. In one patient, it was performed post-CRT because of
the evidence of evolutive disease with a gastric outlet
obstruction and in another patient because of persisting
inoperability at exploratory laparotomy. In the remaining
three patients, there was no possibility for a surgical pro-
cedure and two cases continued with gemcitabine accord-
ing to the study protocol.
Table 1: Volume of PTV per patient and the mean dose to the
PTV (% of prescribed dose and absolute dose)
PTV (planning target volume)
PatientVolumeMean dose %Mean dose Gy
Patient 1
Patient 2
Patient 3
Patient 4
Patient 5
Patient 6
Patient 7
Patient 8
Patient 9
Patient 10
Patient 11
Patient 12
Patient 13
445.6
539.9
396
590.2
637.1
200.3
318
720.6
419.5
536.7
869
529.7
589.8
99.7
100.2
100.1
100.4
99.1
100.5
101
101.8
101.7
101.9
100.1
100.8
99
44.9
45.1
45.1
45.2
44.6
45.2
45.5
55
54.9
55
54.1
54.4
53.5

Page 5

Radiation Oncology 2008, 3:30 http://www.ro-journal.com/content/3/1/30
Page 5 of 7
(page number not for citation purposes)
Surgical results
Five of the 13 patients underwent a Whipple procedure.
One required a reconstruction of the portal vein; two
other procedures required a splenectomy, of which one
also included an en bloc resection of the left kidney. There
was no postoperative death, and only one patient suffered
from a complication (bilateral pneumonia, medically
treated). Two patients have no evidence of disease (one
patient in the 45 Gy cohort and one patient in 54 Gy
cohort). From the three remaining patients in the group
with resection, one had an omental metastasis at surgery
and received gemcitabine thereafter, and the other two
presented with local failure and/or metastases, so a treat-
ment with systemic gemcitabine was started.
Long-term outcome and survival
The overall median survival for the 13 study patients was
20.3 months. Three of 5 patients in the 45 Gy cohort were
operated on, and 2 of 6 in the 54 Gy cohort. The median
disease free and 2-year overall survival for the group with
resection was 12.6 months and 39%. Three patients are
alive at the time of this report and 2 of them have no evi-
dence of disease (1 patient in the 45 Gy cohort and 1
patient in 54 Gy cohort). They both underwent a com-
plete surgical resection. The third patient is currently
treated with gemcitabine and has a stable disease.
Discussion
The primary objective of this trial was to determine the
MTD of escalating doses of radiation therapy that could be
delivered concurrently with a fixed dose of gemcitabine
(300 mg/m2), administered on a weekly basis, within the
same overall treatment time. We have concluded that a
dose escalation to 54 Gy in 1.8 Gy fractions in an acceler-
ated fractionation regimen was the MTD. GI toxicity was
the DLT. Therefore we do not recommend this dose for
further investigation.
Varying doses and schedules of gemcitabine and concom-
itant RT for patients with locally advanced pancreatic can-
cer have been investigated, mainly in phase I clinical trials
[16,18-20]. Gemcitabine 300 – 600 mg/m2/week given as
a once weekly infusion concurrent with conventional RT
of 50.4 Gy was reported to be reasonably well tolerated
with some indication of anti-tumour activity [13,15,16].
In a phase I study by McGinn et al. to find the MTD of
gemcitabine in association with RT to 50.4 Gy in 1.8 Gy
daily fractions in patients with locally advanced non-
resectable pancreatic cancer, a DLT was reported in 3 of 13
patients [21]. Ten patients did not experience a DLT at the
following dose levels: 200 mg/m2 (3 patients), 300 mg/m2
(4 patients) and 400 mg/m2 (3 patients). One patient had
a DLT as a result of grade 3 neutropenia at a dose of 300
mg/m2 gemcitabine weekly. The most frequently reported
toxicities were GI (nausea and vomiting). Therefore a dose
of gemcitabine 300 mg/m2 on a weekly basis was chosen
in our study. This was a precaution measure, to take into
account the expected additional toxic effects of gemcitab-
ine concurrently with dose-escalated accelerated RT.
Despite this, the escalation to a 54 Gy dose level in an
accelerated regimen was shown to be not feasible.
McGinn et al. published the results of a phase I trial where
the investigators also combined a fixed weekly dose of
gemcitabine (1000 mg/m2) with an escalating dose of RT
[20]. Escalation was achieved by increasing the fraction
size in increments of 0.2 Gy, keeping the duration of radi-
ation constant at 3 weeks. The starting dose was 30 Gy (in
2 Gy fractions) and the final dose investigated (42 Gy in
2.8 Gy fractions) was not recommended for further study
considering the (potential) occurrence of both acute and
late toxicity. As in our study, the acute toxicity consisted of
dose-limiting GI toxicity. Application of the linear quad-
ratic model indicates that 42 Gy in 2.8 Gy-fractions is bio-
logically equivalent to 50.4 Gy in 1.8 Gy-fractions, a
standard dose and fractionation schedule used in the
treatment of patients with unresectable pancreatic cancer.
However, a radiation dose of 36 Gy in 2.4 Gy-fractions
was well tolerated and this is biologically equivalent to
approximately 41.4 Gy in 1.8 Gy-fractions with regard to
late effects. Also the radiation field size was defined much
smaller than radiation field sizes used in our CRT regi-
men, because the RT volume is the most critical variable
influencing GI toxicity in gemcitabine-based CRT regi-
Table 2: GI toxicity: The different GI toxicities experienced (nausea, vomiting and diarrhoea) for each dose cohort.
Gastro-intestinal (GI) toxicity
45 Gy cohort (7 patients)
Vomiting
54 Gy cohort (6 patients)
Vomiting NauseaDiarrhoea NauseaDiarrhoea
Grade 0
Grade 1
Grade 2
Grade 3
Grade 4
0/7
2/7
5/7
0/7
0/7
1/7
4/7
2/7
0/7
0/7
5/7
2/7
0/7
0/7
0/7
0/6
0/6
3/6
3/6
0/6
0/6
3/6
2/6
1/6
0/6
2/6
3/6
1/6
0/6
0/6

Page 6

Radiation Oncology 2008, 3:30http://www.ro-journal.com/content/3/1/30
Page 6 of 7
(page number not for citation purposes)
mens. Nevertheless, McGinn et al. did not report on an
excess in local or regional failures by this reduction in
radiation dose and field size.
The inclusion of prophylactic nodal basins in the treat-
ment volume, resulting in a large volume of normal tissue
irradiated with increased radiosensitization of normal tis-
sues, in combination with the accelerated fractionation
and dose escalation, may have led to the toxicity pattern
described in our study. Therefore, it is recommended to
use guidelines for standardised treatment and volume
delineation. Efforts have been put to identify the elective
lymphatic target volume in pancreatic cancer and the large
topographic variability of upper abdominal lymphatics
may have consequences on PTV definition, resulting in an
adaptation of the treated volume [22,23]. Also, the adap-
tation of the PTV according to the dynamic MRI, to
account for the potential shift of the target volume due to
respiration, has led to an increased radiation volume
(mean PTV volume was 522.5 cm3). The recommended
dose level according to our results is 45 Gy in 1.8 Gy frac-
tions. When dose escalation in an altered fractionation
regimen is considered, this has to be performed more con-
servatively. Perhaps it would have been more feasible if
we had given an extra fraction in week 1, 3 and 5 in the
first dose escalation cohort to a total dose of 50.4 Gy, fol-
lowed by an evaluation of this group and then we could
have added one fraction per week.
Equally encouraging is the observation that the median
survival in this group of patients with a dismal prognosis
was 20.3 months, indicating that CRT may play a role in
the therapy of borderline resectable or unresectable LAPC.
Another important field of interest and future research
which may lead to a significant clinical impact on therapy
for this poor prognostic cancer, is the combination of
molecular targeted agents like nelfinavir [24] or erlotinib,
gefitinib and bevacizumab [25-27] with a CRT regimen,
although further confirmation of initial positive results in
phase I studies is warranted by randomised trials.
Conclusion
This gemcitabine-based CRT regimen with accelerated
dose escalation is clearly not feasible. GI toxicity is the
DLT. However, the median survival and the number of
inoperable patients becoming resectable, indicate that
there might be a role for the investigation of CRT with a
fixed dose of gemcitabine and concurrent RT with small
fractions (1.8 Gy/day) in borderline resectable or unre-
sectable non-metastatic LAPC.
Competing interests
The authors declare that they have no competing interests.
Authors' contributions
All authors read and approved the final manuscript. TB
analysed the patient data and drafted the manuscript. KH
participated in the study design and the patient evaluation
and study enrolment and helped to draft the manuscript.
EVC participated in the study design and the patient eval-
uation and study enrolment and helped to draft the man-
uscript. WVS participated in the patient evaluation and
study enrolment. BT participated in the patient evaluation
and study enrolment. RA participated in the patient eval-
uation and study enrolment. NE participated in the
patient evaluation. DB participated in the patient evalua-
tion. DVB participated in the patient evaluation. LG par-
ticipated in the study design and patient follow up during
RT. CV participated in the patient evaluation and study
enrolment and helped to draft the manuscript.
Acknowledgements
Part of this work was supported by an educational grant of Eli Lilly Benelux
NV.
References
1.Bramhall SR, Allum WH, Jones AG, Allwood A, Cummins C, Neop-
tolemos JP: Treatment and survival in 13,560 patients with
pancreatic cancer, and incidence of the disease, in the West
Midlands: an epidemiological study. Br J Surg 1995, 82:111-115.
2.Jemal A, Siegel R, Ward E, Murray T, Xu J, Thun MJ: Cancer statis-
tics, 2007. CA Cancer J Clin 2007, 57:43-66.
3.Fernandez E, La VC, Porta M, Negri E, d'Avanzo B, Boyle P: Pancre-
atitis and the risk of pancreatic cancer. Pancreas 1995,
11:185-189.
4.Yeo CJ, Cameron JL, Lillemoe KD, Sitzmann JV, Hruban RH, Good-
man SN, et al.: Pancreaticoduodenectomy for cancer of the
head of the pancreas. 201 patients. Ann Surg 1995, 221:721-731.
5.Geer RJ, Brennan MF: Prognostic indicators for survival after
resection of pancreatic adenocarcinoma. Am J Surg 1993,
165:68-72.
6. Sperti C, Pasquali C, Piccoli A, Pedrazzoli S: Recurrence after
resection for ductal adenocarcinoma of the pancreas. World
J Surg 1997, 21:195-200.
7.Moertel CG, Frytak S, Hahn RG, O'Connell MJ, Reitemeier RJ, Rubin
J, et al.: Therapy of locally unresectable pancreatic carcinoma:
a randomized comparison of high dose (6000 rads) radiation
alone, moderate dose radiation (4000 rads + 5-fluorouracil),
and high dose radiation + 5-fluorouracil: The Gastrointesti-
nal Tumor Study Group. Cancer 1981, 48:1705-1710.
8. Burris HA III, Moore MJ, Andersen J, Green MR, Rothenberg ML,
Modiano MR, et al.: Improvements in survival and clinical ben-
efit with gemcitabine as first-line therapy for patients with
advanced pancreas cancer: a randomized trial. J Clin Oncol
1997, 15:2403-2413.
9.Lawrence TS, Chang EY, Hahn TM, Hertel LW, Shewach DS: Radio-
sensitization of pancreatic cancer cells by 2',2'-difluoro-2'-
deoxycytidine. Int J Radiat Oncol Biol Phys 1996, 34:867-872.
10.Lawrence TS, Eisbruch A, Shewach DS: Gemcitabine-mediated
radiosensitization. Semin Oncol 1997, 24:S7.
11.Mason KA, Milas L, Hunter NR, Elshaikh M, Buchmiller L, Kishi K, et
al.: Maximizing therapeutic gain with gemcitabine and frac-
tionated radiation. Int J Radiat Oncol Biol Phys 1999, 44:1125-1135.
12.Gregoire V, Hittelman WN, Rosier JF, Milas L: Chemo-radiother-
apy: radiosensitizing nucleoside analogues (review). Oncol
Rep 1999, 6:949-957.
13.Li CP, Chao Y, Chi KH, Chan WK, Teng HC, Lee RC, et al.: Concur-
rent chemoradiotherapy treatment of locally advanced pan-
creatic cancer: gemcitabine versus 5-fluorouracil, a
randomized controlled study. Int J Radiat Oncol Biol Phys 2003,
57:98-104.

Page 7

Publish with BioMed Central and every
scientist can read your work free of charge
"BioMed Central will be the most significant development for
disseminating the results of biomedical research in our lifetime."
Sir Paul Nurse, Cancer Research UK
Your research papers will be:
available free of charge to the entire biomedical community
peer reviewed and published immediately upon acceptance
cited in PubMed and archived on PubMed Central
yours — you keep the copyright
Submit your manuscript here:
http://www.biomedcentral.com/info/publishing_adv.asp
BioMedcentral
Radiation Oncology 2008, 3:30http://www.ro-journal.com/content/3/1/30
Page 7 of 7
(page number not for citation purposes)
14.Nguyen LN, Ang KK: Radiotherapy for cancer of the head and
neck: altered fractionation regimens. Lancet Oncol 2002,
3:693-701.
McGinn CJ, Zalupski MM: Radiation therapy with once-weekly
gemcitabine in pancreatic cancer: current status of clinical
trials. Int J Radiat Oncol Biol Phys 2003, 56:10-15.
Poggi MM, Kroog GS, Russo A, Muir C, Cook J, Smith J, et al.: Phase
I study of weekly gemcitabine as a radiation sensitizer for
unresectable pancreatic cancer. Int J Radiat Oncol Biol Phys 2002,
54:670-676.
Bussels B, Goethals L, Feron M, Bielen D, Dymarkowski S, Suetens P,
et al.: Respiration-induced movement of the upper abdominal
organs: a pitfall for the three-dimensional conformal radia-
tion treatment of pancreatic cancer. Radiother Oncol 2003,
68:69-74.
Blackstock AW, Bernard SA, Richards F, Eagle KS, Case LD, Poole
ME, et al.: Phase I trial of twice-weekly gemcitabine and con-
current radiation in patients with advanced pancreatic can-
cer. J Clin Oncol 1999, 17:2208-2212.
McGinn CJ, Lawrence TS, Zalupski MM: On the development of
gemcitabine-based chemoradiotherapy regimens in pancre-
atic cancer. Cancer 2002, 95:933-940.
McGinn CJ, Zalupski MM, Shureiqi I, Robertson JM, Eckhauser FE,
Smith DC, et al.: Phase I trial of radiation dose escalation with
concurrent weekly full-dose gemcitabine in patients with
advanced pancreatic cancer. J Clin Oncol 2001, 19:4202-4208.
McGinn CJ, Smith DC, Szarka CE: A phase I study of gemcitabine
(GEM) in combination with radiation therapy (RT) in
patients with localized, unresectable pancreatic cancer
[abstract]. Proc Am Soc Clin Oncol 1998, 17:264a.
Brunner TB, Baum U, Grabenbauer GG, Sauer R, Lambrecht U:
Large topographic variability of upper abdominal lymphatics
and the consequences for radiation treatment planning. Radi-
other Oncol 2006, 81:190-195.
Brunner TB, Merkel S, Grabenbauer GG, Meyer T, Baum U, Papa-
dopoulos T, et al.: Definition of elective lymphatic target vol-
ume in ductal carcinoma of the pancreatic head based on
histopathologic analysis. Int J Radiat Oncol Biol Phys 2005,
62:1021-1029.
Brunner TB, Geiger M, Grabenbauer GG, Lang-Welzenbach M, Man-
toni TS, Cavallaro A, et al.: Phase I trial of the human immuno-
deficiency virus protease
chemoradiation for locally advanced pancreatic cancer. J Clin
Oncol 2008, 26:2699-2706.
Czito BG, Willett CG, Bendell JC, Morse MA, Tyler DS, Fernando
NH, et al.: Increased toxicity with gefitinib, capecitabine, and
radiation therapy in pancreatic and rectal cancer: phase I
trial results. J Clin Oncol 2006, 24:656-662.
Duffy A, Kortmansky J, Schwartz GK, Capanu M, Puleio S, Minsky B,
et al.: A phase I study of erlotinib in combination with gemcit-
abine and radiation in locally advanced, non-operable pan-
creatic adenocarcinoma. Ann Oncol 2008, 19:86-91.
Crane CH, Ellis LM, Abbruzzese JL, Amos C, Xiong HQ, Ho L, et al.:
Phase I trial evaluating the safety of bevacizumab with con-
current radiotherapy and capecitabine in locally advanced
pancreatic cancer. J Clin Oncol 2006, 24:1145-1151.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
inhibitor nelfinavir and
25.
26.
27.