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ABSTRACT: The optimal role of radiotherapy (RT) to the prostate bed after radical prostatectomy (RP) is the subject of much debate. In this study, the results of adjuvant RT (ART) and salvage RT (SRT) were compared.
A total of 146 lymph node-negative patients were treated postoperatively after RP with RT to the prostate bed between 1987 and 1998. Of these, 75 patients had an undetectable prostate-specific antigen (PSA) level and were treated with ART for adverse pathologic features only to a median dose of 60 Gy (range 51-70). A positive margin was identified in 96%, and two of the three with negative margins had seminal vesicle involvement (SVI). SRT was administered for either a persistently detectable PSA level after RP (n = 27) or for a delayed rise in PSA (n = 44) to a median dose of 70 Gy (range 60-78). Adjuvant androgen ablation was given to 37 patients; 2 who had received ART and 35 had who received SRT. The median duration of androgen ablation was 24 months. The primary end point was freedom from biochemical failure (bNED), which was considered to be an undetectable PSA level. The median follow-up was 53 months for all patients: 68 months for the ART patients and 35 months for the SRT patients.
For the ART group, 8 patients subsequently developed a rising PSA level. The 5-year bNED rate was 88%. SVI was the strongest predictor of outcome, with a 5-year bNED rate of 94% for those without SVI and 65% for those with SVI (p = 0.0002). SVI was the only significant factor in Cox proportional hazards regression analysis in the ART cohort. For the SRT group, 20 patients developed a rising PSA level after RT. The 5-year bNED rate was 66% for all SRT patients, and 43% and 78% in those with a persistently detectable PSA and those with a delayed rise in PSA, respectively. In the Cox proportional hazards regression analysis, this subdivision of SRT was statistically significant. Moreover, when the Cox model included all patients and variables, the timing of RT (ART vs. SRT) was an independent correlate of bNED, as was androgen ablation.
For RP patients with high-risk pathologic features, the timing of postoperative RT and the PSA status after RP were strong determinants of outcome. Because of the potential confounding factors, direct comparisons of ART and SRT are problematic; however, ART is extremely effective and offers the surest approach for maintaining biochemical control.
International Journal of Radiation OncologyBiologyPhysics 08/2003; 56(3):755-63. · 4.11 Impact Factor
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ABSTRACT: The majority of clinical trials have shown that high-grade prostate cancer patients treated with androgen deprivation (AD) plus radiation (RT) have a survival advantage over those treated with RT alone. One possible mechanism for such a favorable interaction is that AD sensitizes cells to radiation. Animal model studies have provided suggestive evidence that AD sensitizes cells to radiation, but this mechanism is difficult to confirm conclusively in vivo. This question was investigated in LNCaP cells grown in vitro.
LNCaP cells were cultured in vitro in Dulbecco's modified Eagle's medium (DMEM)-F12 medium, containing 10% fetal bovine serum (complete medium [CM]). AD was achieved by culture in charcoal-stripped serum (SS)-containing medium. Replacement of androgen was done by adding the synthetic androgen R1881 at 1 x 10(-10) M to SS. Apoptosis was measured with a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. Clonogenic survival was used to determine overall cell death, and the results were corrected for differences in plating efficiency from the various growth conditions.
LNCaP cells were grown in CM, SS, or SS + R1881 medium, and cell counts obtained at 3, 4, and 5 days. Cell number increased exponentially in CM, whereas no increase in cell number was observed in SS medium. Cell counts from growth in SS + R1881 were intermediate between these extremes. Apoptosis was measured to determine if the combination of AD + RT in vitro resulted in supra-additive cell death, as has been previously described in an in vivo model system. The cells were cultured for 3 days before RT and apoptosis quantified 24 h after RT. There was a consistent supra-additive increase in apoptosis in cells exposed to AD + RT (2 or 8 Gy), as compared to either treatment given individually. In contrast, significant radiosensitization by AD was not observed by clonogenic survival even when the conditions of AD were varied. No radiosensitization was observed upon incubation in SS medium for 3, 4, or 5 days before RT, or extending AD after RT for 6 h before plating or 24 h after plating.
The results show that in LNCaP prostate tumor cells supra-additive apoptosis does not translate into radiosensitization by clonogenic survival. Because clonogenic survival is a measure of overall cell death, either the level of apoptosis is too small a component of overall cell death or the increases in apoptosis occurred in a subpopulation that would have been killed by other mechanisms. Although the findings indicate that AD does not act by sensitizing prostate cancer cells to RT, the additive cell death and growth inhibitory effects of AD + RT are clinically meaningful.
International Journal of Radiation OncologyBiologyPhysics 12/2001; 51(4):1002-7. · 4.11 Impact Factor
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ABSTRACT: To compare the outcome of patients with Stage II seminoma treated with prophylactic mediastinal irradiation, without any supradiaphragmatic irradiation, and with prophylactic left supraclavicular irradiation (PLSCI).
Between 1960 and 1999, 73 men with Stage II seminoma received postorchiectomy radiotherapy. Before 1984, 36 received prophylactic mediastinal irradiation (Series I); between 1984 and 1992, 17 received no supradiaphragmatic irradiation (Series II); and after 1992, 20 received PLSCI (Series III). The outcomes in these series were compared.
The abdominal tumor sizes were as follows: Series I, <or=2 cm, n = 4; >2 and <or=5 cm, n = 12; >5 and <or=10 cm, n = 16; Series II, <or=2 cm, n = 1; >2 and <or=5 cm, n = 12; >5 and <or=10 cm, n = 4; and Series III, <or=2 cm, n = 1; >2 and <or=5 cm, n = 14; >5 and <or=10 cm, n = 5 (p = 0.75). The median duration of follow-up was 14.4, 9.3, and 4.5 years for Series I, II, and III, respectively. The 6-year freedom from relapse was 94%, 71%, and 95% for Series I, II, and III, respectively. The differences between Series I and II (p = 0.014) and between II and III (p = 0.042) were significant. Three patients in Series II had a relapse in their left supraclavicular fossa-a failure pattern abrogated by PLSCI.
PLSCI significantly diminishes the likelihood of relapse for Stage IIA, IIB, and IIC seminoma (mass <or=10 cm).
International Journal of Radiation OncologyBiologyPhysics 11/2001; 51(3):643-9. · 4.11 Impact Factor
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ABSTRACT: To determine the outcome for node-positive prostate cancer treated by early androgen ablation with or without prostatic radiation.
Two hundred fifty-five men with lymphadenectomy-proven pelvic nodal metastases treated with early androgen ablation alone (n = 183) or with combined ablation and radiation (n = 72) between 1984 and 1998 were retrospectively reviewed for disease outcome and survival. Post-treatment disease status was based on the prostate-specific antigen levels or on the clinical and radiographic status for patients treated before 1987. Univariate and multivariate statistics were used to determine the prognostic factors and assess the influence of radiation treatment.
With a median follow-up of 9.4 years, the 5, 10, and 13-year overall survival rate for those treated with early ablation alone was 83%, 46%, and 21%, respectively. The freedom from relapse or rising prostate-specific antigen rate for these patients was 41%, 25%, and 19% at 5, 10, and 13 years, respectively. Distant metastasis and local recurrence occurred with a 10-year actuarial incidence of 44% and 51%, respectively. With a median follow-up of 6.2 years, the 5 and 10-year overall survival rate for those treated with radiation and ablation was 92% and 67%, respectively. The freedom from relapse or rising prostate-specific antigen rate in these men was 91% and 80% at 5 and 10 years, respectively. The superior outcome for combined ablation and radiation was substantial and statistically significant in the univariate and multivariate analyses.
Early androgen ablation alone has little curative potential for node-positive prostate cancer. The addition of prostatic radiation to ablation resulted in substantial and significant improvement in disease control and patient survival.
Urology 09/2001; 58(2):233-9. · 2.43 Impact Factor
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ABSTRACT: An approach to treatment plan optimization is presented that inputs dose--volume constraints and utilizes a feasibility search algorithm that seeks a set of beam weights so that the calculated dose distributions satisfy the dose--volume constraints. In contrast to a search for the "best" plan, this approach can quickly determine feasibility and point out the most restrictive of the predetermined constraints.
The cyclic subgradient projection (CSP) algorithm was modified to incorporate dose--volume constraints in a treatment plan optimization schema. The algorithm was applied to determine beam weights for several representative three-dimensional treatment plans.
Using the modified CSP algorithm, we found that either a feasible solution to the dose--volume constraint problem was found or the program determined, after a predetermined set of iterations was performed, that no feasible solution existed for the particular set of dose--volume constraints. If no feasible solution existed, we relaxed several of the dose--volume constraints and were able to achieve a feasible solution.
Feasibility search algorithms can be used in radiation treatment planning to generate a treatment plan that meets the dose--volume constraints established by the radiation oncologist. In the absence of a feasible solution, these algorithms can provide information to the radiation oncologist as to how the dose--volume constraints may be modified to achieve a feasible solution.
International Journal of Radiation OncologyBiologyPhysics 05/2001; 49(5):1419-27. · 4.11 Impact Factor
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ABSTRACT: The effect of adenoviral-mediated p53 transgene expression on the radiation response of two human prostate cancer cell lines, the p53(wild-type) LNCaP and p53(null) PC3 lines, was examined. The objective was to determine if this vector sensitizes cells to radiation independently of their p53 status.
A recombinant adenovirus-5 vector (RPR/INGN 201, Introgen Therapeutics, Houston, TX) containing a CMV promoter and wild-type p53-cDNA (Ad5-p53) was used to facilitate p53 transgene expression. A multiplicity of infection (MOI) of 10-40 viral particles per cell was used, based on Ad5/CMV/lacz infection and staining for the beta-galactosidase reporter gene product. Clonogenic assays were performed to evaluate the degree of sensitization to radiation of viral-transduced cells compared with irradiated nontransduced controls. The relative efficacy of these treatments to induce apoptotic cell death was determined using the TUNEL assay.
The delivery of Ad5-p53 (10 MOI) reduced control plating efficiency from 36.5% to 0.86% in the LNCaP cell line and from 75.1% to 4.1% in the PC3 cell line. After correcting for the effect of Ad5-p53 on plating efficiency, the surviving fraction after 2 Gy (SF2) of gamma-irradiation was reduced over 2.5-fold, from 0.187 to 0.072, with transgene p53 expression in the LNCaP cell line. Surviving fraction after 4 Gy (SF4) was reduced over 4.5-fold, from 0.014 to 0.003, after Ad5-p53 treatment. In the PC3 cell line, Ad5-p53 (40 MOI) reduced SF2 over 1.9-fold from 0.708 to 0.367, and SF4 over 6-fold from 0.335 to 0.056. In both the LNCaP and PC3 cell lines, the combination of Ad5-p53 plus radiation (2 Gy) resulted in supra-additive apoptosis (approximately 20% for LNCaP and approximately 15% for PC3 at 50 MOI), above that seen from the addition of the controls; control vector Ad5-pA plus RT (0.15% for LNCaP and 1.44% for PC3), Ad5-p53 alone (28.6% for LNCaP and 21.7% for PC3), RT alone (0% for LNCaP and 0.23% for PC3), or Ad5-pA alone (0.1% for LNCaP and 0.29% for PC3).
The clonogenic survival and apoptosis data demonstrate that p53 transgene expression sensitizes human prostate adenocarcinoma cells in vitro to irradiation. As this effect was observed in both the p53(wild-type) LNCaP and p53(null) PC3 lines, radiosensitization was independent of p53 status.
International Journal of Radiation OncologyBiologyPhysics 01/2001; 48(5):1507-12. · 4.11 Impact Factor
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ABSTRACT: To determine the effect of radiotherapy dose on prostate cancer patient outcome and biopsy positivity in a phase III trial.
A total of 305 stage T1 through T3 patients were randomized to receive 70 Gy or 78 Gy of external-beam radiotherapy between 1993 and 1998. Of these, 301 were assessable; stratification was based on pretreatment prostate-specific antigen level (PSA). Dose was prescribed to the isocenter at 2 Gy per fraction. All patients underwent planning pelvic computed tomography scan to confirm prostate position. Treatment failure was defined as an increasing PSA on three consecutive follow-up visits or the initiation of salvage treatment. Median follow-up was 40 months.
One hundred fifty patients were randomized to the 70-Gy arm and 151 to the 78-Gy arm. The difference in freedom from biochemical and/or disease failure (FFF) rates of 69% and 79% for the 70-Gy and 78-Gy groups, respectively, at 5 years was marginally significant (log-rank P: =.058). Multiple-covariate Cox proportional hazards regression showed that the study randomization was an independent correlate of FFF, along with pretreatment PSA, Gleason score, and stage. The patients who benefited most from the 8-Gy dose escalation were those with a pretreatment PSA of more than 10 ng/mL; 5-year FFF rates were 48% and 75% (P: =.011) for the 70-Gy and 78-Gy arms, respectively. There was no difference between the arms ( approximately 80% 5-year FFF) when the pretreatment PSA was < or = 10 ng/mL.
A modest dose increase of 8 Gy using conformal radiotherapy resulted in a substantial improvement in prostate cancer FFF rates for patients with a pretreatment PSA of more than 10 ng/mL. These findings document that local persistence of prostate cancer in intermediate- to high-risk patients is a major problem when doses of 70 Gy or less are used.
Journal of Clinical Oncology 01/2001; 18(23):3904-11. · 18.37 Impact Factor
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ABSTRACT: An adenovirus 5 vector containing wild-type p53 cDNA (Ad5-p53) and a cytomegalovirus promoter was used to generate p53 transgene expression. Control vector (Ad5-pA) contained the poly-adenosine sequence. PC3 cells (2 x 10(6)) were injected s.c. into the legs of nude mice. Treatment with Ad5-p53 was initiated at a tumor volume of 200 mm3. Three intratumoral injections (days 1, 4, and 7) were given with 3 x 10(8) plaque-forming units, followed by 5 Gy pelvic irradiation (day 8) in one fraction using a cobalt-60 source. Tumor volume measurements were obtained every 2 days. LNCaP cells (2 x 10(6)) were injected orthotopically into the prostates of nude mice, and tumor weight was approximated using serum prostate-specific antigen (PSA) obtained from weekly tail vein bleedings. The target PSA for the start of the studies was 5 ng/ml. The intraprostatic injections of Ad5-p53 were done twice (days 1 and 2) and followed by 5 Gy pelvic irradiation on day 3. The PC3 tumor volume growth curves were log transformed and fitted using linear regression. The times (in days) for the tumors to reach 500 mm3 were calculated as 10.7 +/- 0.7 (+/- SE) for the saline control (no virus), 9.8 +/- 2.1 for Ad5-pA, 15.6 +/- 1.6 for Ad5-p53, 14.6 +/- 1.5 radiation therapy (RT; 5 Gy), 14.6 +/- 1.5 for Ad5-pA plus RT, and 31.4 +/- 5.3 for Ad5-p53 plus RT. The Ad5-p53 plus RT times were significantly different from the other groups. An enhancement factor of 3.4 was calculated, indicating supra-additivity. LNCaP tumor growth was determined via weekly serum PSA measurements. Treatment failure was determined using two PSA-based methods; a serum PSA of > 1.5 ng/ml or two rises in PSA during 6 weeks posttreatment. The results were similar using either end point. Treatment with Ad5-p53 plus 5 Gy resulted in significantly fewer PSA failures (<30%), as compared with Ad5-p53 alone (64-73%) and the other controls (approximately 80-100%) These results are also consistent with a supra-additive inhibition of tumor growth. Tumor growth in vivo was inhibited supra-additively when p53null and p53wildtype prostate tumors were treated with Ad5-p53 and 5 Gy radiation.
Clinical Cancer Research 12/2000; 6(11):4402-8. · 7.74 Impact Factor
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ABSTRACT: To compare early and late side effects in prostate cancer patients with Stage T1b-T3 disease randomized to receive 70 Gy or 78 Gy.
There were 189 patients randomized with a minimum follow-up of 2 years, that were available for this analysis. All patients were initially treated with a 4-field box to an isocenter dose of 46 Gy at 2 Gy per fraction. In the 70-Gy arm, treatment was continued to a reduced volume using a 4-field box technique. In the 78-Gy arm, treatment was continued to a reduced volume using a conformal 6-field arrangement. Side effects were graded on a 1-4 scale, adapted from Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria.
No significant differences in acute rectal or bladder toxicity were seen between the two treatment techniques (p > 0.6 for all comparisons). The 5-year Kaplan-Meier risks of Grade 2 or higher late bladder toxicity were 20% and 9% for 70-Gy and 78-Gy groups, respectively (log rank, p = 0.8). The 5-year risks of Grade 2 or higher late rectal toxicity were 14% and 21% for 70 Gy and 78 Gy, respectively (p = 0.4). Dose-volume histogram analysis of the 78-Gy patients showed a significant correlation between the percentage of rectum irradiated to 70 Gy or greater and the likelihood of developing late rectal complications. Patients with more than 25% of the rectum receiving 70 Gy or greater had a 5-year risk of Grade 2 or higher complications of 37% compared to 13% for patients with 25% or less (p = 0.05). All three Grade 3 complications occurred when greater than 30% of the rectum received 70 Gy or more.
The overall rate of complications was similar in both treatment arms. However, there is evidence for a significant increase in late rectal complications when more than 25% of the rectum received 70 Gy or greater. This parameter may serve as a benchmark for the design of future three-dimensional conformal trials.
International Journal of Radiation OncologyBiologyPhysics 10/2000; 48(3):635-42. · 4.11 Impact Factor
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ABSTRACT: Cystosarcoma phyllodes is a rare sarcoma of the breast. Although surgical removal is the mainstay of treatment, the extent of surgery required (excision vs. mastectomy) and the need for additional local therapy, such as radiotherapy, are unclear. The current study evaluated the rate of local and distant failure, as well as potential prognostic factors, to better define appropriate treatment strategies.
One hundred one patients treated primarily for cystosarcoma phyllodes of the breast were evaluated. These tumors were classified histologically into benign (58%), indeterminate (12%), and malignant (30%) based on well defined criteria. Stromal overgrowth (29%) was considered separately. Surgery was comprised of local excision with breast conservation (47%) or mastectomy (53%). Microscopic surgical margins were negative in 99% of cases. Six patients received adjuvant radiotherapy.
Overall survival for the 101 patients was 88%, 79%, and 62% at 5, 10, and 15 years, respectively. For patients with nonmalignant (benign or indeterminate) and malignant cystosarcoma phyllodes, the overall survival was 91% and 82%, respectively, at 5 years, and 79% and 42%, respectively, at 10 years. Similar rates were observed based on the presence or absence of stromal overgrowth. Local recurrence occurred in 4 patients, with an actuarial 10-year rate of 8%. Eight patients developed distant metastases, with an actuarial 10-year rate of 13%. Multivariate analysis using Cox proportional hazards regression revealed stromal overgrowth to be the only independent predictor of distant failure.
Local failure in this group of largely margin negative patients with cystosarcoma phyllodes of the breast was low, showing that breast-conserving surgery with appropriate margins is the preferred primary therapy. The current study data do not support the use of adjuvant radiotherapy for patients with adequately resected disease. Patients with stromal overgrowth, particularly when the tumor size was > 5 cm, were found to have a high rate of distant failure; such patients merit consideration of a trial that examines the efficacy of systemic therapy.
Cancer 10/2000; 89(7):1502-11. · 4.77 Impact Factor
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ABSTRACT: Screening pedigrees for inherited minisatellite length changes provides an efficient means of monitoring repeat DNA instability but has given rise to apparently contradictory results regarding the effects of radiation on the human germline. To explore this further in individuals with known radiation doses and to potentially gain information on the timing of mutation induction, we have used an extremely sensitive single molecule approach to quantify the frequencies of mutation at the hypervariable minisatellites B6.7 and CEB1 in the sperm of three seminoma patients following hemipelvic radiotherapy. Scattered radiation doses to the testicles were monitored and pre-treatment sperm DNA was compared with sperm derived from irradiated pre-meiotic, meiotic and post-meiotic cells. We show no evidence for mutation induction in any of the patients and discuss this finding in the context of previous population studies using minisatellites as reporter systems, one of which provided evidence for radiation-induced germline mutation.
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 10/2000; 453(1):67-75. · 2.85 Impact Factor
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ABSTRACT: To characterize the relationship of radiotherapy dose to prostate cancer patient outcome, with an emphasis on the influence of pretreatment prognostic variables.
The 1127 Stage T1-T4 prostate cancer patients examined were treated consecutively with definitive external beam radiotherapy at the University of Texas-M.D. Anderson Cancer Center from 1987 to 1997. All had a pretreatment prostate-specific antigen (PSA) level. Treatment failure was defined as two consecutive PSA elevations on follow-up. There were 994 patients treated with a four-field box throughout to 60-70 Gy after a small reduction at 46 Gy and 161 treated with a six-field conformal boost after 46 Gy to 74-78 Gy. No patient received neoadjuvant or adjuvant androgen ablation. Median follow-up was 51.8 months.
Patients were divided into three radiotherapy dose groups consisting of </=67 Gy (n = 500), >67-77 Gy (n = 495), and >77 Gy (n = 132). Relative to other prognostic factors, there were fewer patients treated to the highest dose level with a pretreatment PSA (PSAB) </=4 or >20 ng/ml, Stage T3/T4 disease, or a Gleason score of 2-6. Actuarial 4-year freedom from biochemical failure (bNED) rates for the entire cohort were 54%, 71%, and 77% (p < 0.0001) for the low-, intermediate-, and high-dose groups. PSAB, palpable stage, and Gleason score were also highly significant. In Cox proportional hazards regression, dose (p < 0. 0001 as a continuous or categorical variable) was an independent predictor of bNED, as were the other prognostic factors. Pairwise univariate comparisons showed that an increase in dose from </=67 Gy to >67-77 Gy was associated with improved bNED rates for all PSAB (</=10 and >10), stage (T1/T2 and T3/T4), and Gleason score (2-6 and 7-10) subgroups tested. In contrast, the only prognostic group that benefited from raising dose from >67-77 Gy to >77 Gy was patients with a PSAB >10 ng/ml; although trends were noted for Stage T1/T2 and Gleason 2-6 patients. Patients with the combined features of a PSAB >10 ng/ml and Stage T1/T2 disease had 4-year bNED rates of 61% and 93% at the intermediate- and high-dose levels. A strongly significant linear association between dose (60-78 Gy) and 4-year actuarial bNED was demonstrated for patients with these intermediate-risk features.
Prostate cancer dose response to external beam radiotherapy should be considered in the context of pretreatment prognostic factors. Our data indicate that, for favorable patients with a PSAB of </=10 ng/ml, intermediate doses of >67-77 Gy provide the same rate of control as higher doses. However, longer follow-up may reveal a benefit to dose escalation >77 Gy, even in this favorable subset. Substantial and clinically relevant enhancements in bNED were seen at all dose levels for moderate-risk patients, such as those having a PSAB >10 ng/ml and Stage T1/T2 disease. Sustained bNED was not realized for high-risk patients, even using 78 Gy; these patients may be best treated with higher doses, whole pelvic irradiation, and/or androgen ablation plus radiation.
International Journal of Radiation OncologyBiologyPhysics 10/2000; 48(2):507-12. · 4.11 Impact Factor
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ABSTRACT: Estimating the duration of S phase (T(S) ) and the potential doubling time (T(pot) ) from a single time measurement of the movement of cells using bivariate cytometry is common. However, these estimates require an assumption of the duration of G2 + M (T(G2+M) ). Inspection of the measured dynamic quantities, relative movement [RM(t)], fractions of labeled divided and undivided cells (f(lu)(t) and f(ld)(t)) suggests that T(G2+M), T(S), and T(pot) can be determined simultaneously.
An equation connecting the growth of the cell population, time, and the dynamic quantities was determined. The equation cannot be solved analytically, but accurate approximations can be used to find T(pot). From this result, the value of T(G2+M) can be determined from f(ld)(t), and T(S) can be determined from RM(t).
Kinetic parameters obtained from single time estimates using the new method compared to those obtained from the analysis of multiple time-point measurements of MCa-K and MCa-4 murine tumors are shown to be in close agreement. Moreover, estimates of T(G2+M) in MCa-4 tumors, treated with paclitaxel, provide extra information on the changes in T(G2+M). When applied to the rat R3327-G prostate tumor model following androgen ablation, a correlation analysis of the T(pot) values obtained by the new and previous single time-point methods demonstrates that the rank order from shortest to longest T(pot) values are largely preserved.
The new procedure makes direct estimation of T(G2+M) possible from single time-dynamic measurements. The results from previous studies on T(S) and T(pot) are largely unchanged, but extra information is now available.
Cytometry 10/2000; 41(1):1-8.
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L Potters,
C A Perez,
D C Beyer,
J C Blasko,
J D Forman,
D H Hussey,
W R Lee,
S B Paryani, A Pollack,
M Roach,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1383-400. · 5.73 Impact Factor
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A Pollack,
S B Paryani,
D Hussey,
C A Perez,
D C Beyer,
J C Blasko,
J D Forman,
W R Lee,
L Potters,
M Roach,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1401-12. · 5.73 Impact Factor
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M Roach,
J C Blasko,
C A Perez,
D C Beyer,
J D Forman,
D H Hussey,
W R Lee,
S B Paryani, A Pollack,
L Potters,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1441-8. · 5.73 Impact Factor
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J D Forman,
W R Lee,
M Roach,
C A Perez,
D C Beyer,
J C Blasko,
D H Hussey,
S B Paryani, A Pollack,
L Potters,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1373-82. · 5.73 Impact Factor
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W R Lee, A Pollack,
C A Perez,
D C Beyer,
J C Blasko,
J D Forman,
D H Hussey,
S B Paryani,
L Potters,
M Roach,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1413-8. · 5.73 Impact Factor
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C A Perez,
D C Beyer,
J C Blasko,
J D Forman,
D H Hussey,
W R Lee,
S B Paryani, A Pollack,
L Potters,
M Roach,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1419-39. · 5.73 Impact Factor
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C A Perez,
D C Beyer,
J C Blasko,
J D Forman,
D H Hussey,
W R Lee,
S B Paryani, A Pollack,
L Potters,
M Roach,
P Scardino,
P Schellhammer,
S Leibel
Radiology 07/2000; 215 Suppl:1449-72. · 5.73 Impact Factor
