[Show abstract][Hide abstract] ABSTRACT: Because predicting recurrence intervals and patterns would allow for appropriate therapeutic strategies, we evaluated the clinical and pathological characteristics of early and late recurrences of colorectal cancer.
Patients who developed recurrence after undergoing curative resection for colorectal cancer stage I-III between January 2000 and May 2006 were identified. Early recurrence was defined as recurrence within 2 years after primary surgery of colorectal cancer. Analyses were performed to compare the clinicopathological characteristics and overall survival rate between the early and late recurrence groups.
One hundred fifty-eight patients experienced early recurrence and 64 had late recurrence. Multivariate analysis revealed that the postoperative elevation of carbohydrate antigen 19-9 (CA 19-9), venous invasion, and N stage correlated with the recurrence interval. The liver was the most common site of early recurrence (40.5%), whereas late recurrence was more common locally (28.1%), or in the lung (32.8%). The 5-year overall survival rates for early and late recurrence were significantly different (34.7% vs. 78.8%; P < 0.001). Survival rates after the surgical resection of recurrent lesions were not different between the two groups.
Early recurrence within 2 years after surgery was associated with poor survival outcomes after colorectal cancer recurrence. An elevated postoperative CA 19-9 level, venous invasion, and advanced N stage were found to be significant risk factors for early recurrence of colorectal cancer.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: The aim of this study was to compare the long-term outcomes of laparoscopy-assisted surgery (LAP) with those for open surgery (OS) when excising nonmetastatic rectal cancers. METHODS: We reviewed the prospectively collected records of all patients (n = 1,009) undergoing OS or LAP from January 2000 to November 2008 at Kyungpook National University Hospital. We undertook propensity score analyses and compared outcomes for the OS and LAC groups in a 1:1 matched cohort. Covariates in the model for propensity scores included age, gender, preoperative tumor marker level, preoperative chemoradiation status, tumor height from the anal verge, and clinical tumor stage. Subgroup analysis was conducted to evaluate the oncologic safety of LAP in patients with extraperitoneal rectal cancers. RESULTS: There were no significant differences in mortality, morbidity, and pathological quality in the propensity-matched cohort (n = 812). The combined 3-year local recurrence rate for all tumor stages was 3.8 % (95 % confidence intervals [95 % CI], 1.9-5.7 %) in the LAP group and 5.9 % (95 % CI, 3.9-8.3 %) in the OS group (P = .089 by log-rank test). The combined 3-year disease-free survival for all stages was 80.5 % (95 % CI, 76.6-84.4 %) in the LAP group and 82.9 % (95 % CI 79.2-86.6 %) in the OS group (P = .516 by log-rank test). Similar results were confirmed for the subgroup of patients with extraperitoneal rectal cancers. CONCLUSIONS: Laparoscopic rectal excision for rectal cancer is feasible and safe with acceptable oncologic outcomes. Further prospective multicenter trials are warranted before incorporating this technology into routine surgical care.
Annals of Surgical Oncology 05/2013; DOI:10.1245/s10434-013-2981-y · 3.94 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: PURPOSE: We compared oncologic outcomes of laparoscopic surgery following self-expandable metallic stent (SEMS) insertion with one-stage emergency surgical treatment of obstructive left-sided colon and rectal cancers. METHODS: From April 1996 to October 2007, 95 consecutive patients with left-sided obstructive colorectal cancers were included: 25 underwent preoperative stenting and elective laparoscopic surgery (SLAP) and 70 underwent emergency open surgery with intraoperative colon lavage (OLAV). Long-term oncologic outcomes were analyzed on an intention-to-treat basis. RESULTS: There were no significant differences in baseline characteristics of patients between groups. Perineural invasion of the primary tumor was more frequent with SLAP (76 vs. 51.4 %, p = 0.033). The median follow-up was 51 months (range, 4-139 months). There were no significant differences between groups in 5-year overall survival rates (SLAP vs. OLAV, 67.2 vs. 61.6 %, p = 0.385). Five-year disease-free survival rates were also similar between groups (SLAP vs. OLAV, 61.2 vs. 60.0 %, p = 0.932). CONCLUSIONS: Laparoscopic surgery after SEMS was feasible and safe for patients with obstructive left-sided colorectal cancer, and oncologic outcomes were comparable to emergency open surgery with intraoperative colon lavage. These results support the continued use of SLAP in this setting. Further large-scale study is needed to investigate any clinical impact attached to the higher rates of perineural invasion observed in SLAP.
International Journal of Colorectal Disease 08/2012; 28(3). DOI:10.1007/s00384-012-1556-x · 2.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To access the short-term outcomes of simultaneous laparoscopic surgery combined with resection for synchronous lesions in patients with colorectal cancer.
Between March 1996 and April 2010 prospectively collected data were reviewed from 93 consecutive patients who had colorectal cancer and underwent simultaneous multiple organ resection (combined group) and 1090 patients who underwent conventional laparoscopic right hemicolectomy or laparoscopic low/anterior resection for colorectal cancer (non-combined group). In the combined group, there were nine gastric resections, three nephrectomies, nine adrenalectomies, 56 cholecystectomies, and 21 gynecologic resections. In addition, five patients underwent simultaneous laparoscopic resection for three organs. The patient demographics, intra-operative outcomes, surgical morbidity, and short-term outcomes were compared between the two groups (the combined and non-combined groups).
There were no significant differences in the clinicopathological variables between the two groups. The operating time was significantly longer in the combined group than in the non-combined group, regardless of tumor location (laparoscopic right hemicolectomy and laparoscopic low/anterior resection groups; P = 0.048 and P < 0.001, respectively). The other intra-operative outcomes, such as the complications and open conversion rate, were similar in both groups. The rate of post-operative morbidity in the combined group was similar to the non-combined group (combined vs non-combined, 15.1% vs 13.5%, P = 0.667). Oncological safety for the colon and synchronous lesions were obtained in the combined group.
Simultaneous laparoscopic multiple organ resection combined with colorectal cancer is a safe and feasible option in selected patients.
World Journal of Gastroenterology 02/2012; 18(8):806-13. DOI:10.3748/wjg.v18.i8.806 · 2.43 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To compare the surgical outcome and intermediate oncological outcomes for laparoscopic versus open intersphincteric resection (ISR).
Intersphincteric resection has been proposed as an alternative to abdominoperineal resection for selected low rectal cancer cases, but the oncological adequacy of laparoscopic ISR has not been established.
A total of 210 consecutive patients with low rectal cancer who underwent ISR between 1997 and 2009 in 2 institutions were evaluated retrospectively. Patients were classified into an open surgery (OS, n = 80) group and a laparoscopy (LAP, n = 130) group. The primary endpoint was 3-year disease-free survival.
The major complication rates were similar in the LAP and OS groups (5.4% vs 3.8%, respectively; P = 0.428). However, the LAP group had a shorter hospital stay and time to bowel movement compared with the OS group. In the LAP group, operating time was 16 minutes shorter (P = 0.230) and intraoperative blood loss was less (P = 0.002). Median follow-up was 34 months (interquartile range: 20.0-42.5 months). The local recurrence rates were similar in the 2 groups (LAP, 2.6% vs OS, 7.7%; P = 0.184). The combined 3-year disease-free survival for all stages was 82.1% (95% CI: 73.7-90.2%) in the LAP group and 77.0% (95% CI: 66.9%-86.9%) in the OS group (P = 0.523).
Laparoscopic ISR can be performed safely and offers a minimally invasive sphincter-sparing alternative. The oncological adequacy of laparoscopic ISR requires long-term follow-up data, but the intermediate-term outcomes seem equivalent to those achieved with OS.
Annals of surgery 11/2011; 254(6):941-6. DOI:10.1097/SLA.0b013e318236c448 · 7.19 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Situs inversus totalis (SIT) is a rare congenital anomaly characterized by an inversion of the thoracic and abdominal viscera that creates a mirror image. The transposition of the organs imposes special demands on the diagnostic and technical skills of the surgeon, especially when performing laparoscopic surgery. We herein report the case of a 63-year-old man with colon cancer of the hepatic flexure who received a laparoscopic right hemicolectomy. Careful recognition by the surgeon of the mirror image anatomy and skillful use of his left hand resulted in a successful outcome. The surgery was not otherwise different from ordinary cases. Therefore, laparoscopic colectomy is considered to be a safe and feasible option for patients with colorectal cancer and SIT.
Surgery Today 11/2011; 41(11):1538-42. DOI:10.1007/s00595-010-4530-7 · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Laparoscopic salvage surgery for colorectal cancer is a novel but technically challenging option for surgeons. The aim of this study was to evaluate the feasibility and safety of laparoscopic surgery in patients with recurrent or metachronous colorectal cancer in comparison with an open approach.
The data used in this study were obtained from databases, the data of which were collected prospectively from January 1996 to February 2010. Data pertaining to patients, operations, and short-term outcomes were analyzed and compared between open and laparoscopic salvage groups.
Among the 3,425 patients studied, colorectal cancer recurred in 565 patients (16.5%) and 41 patients had colorectal salvage operations. Twenty-six patients with recurrence underwent open surgery and 15 cases underwent laparoscopic surgery. The short-term outcomes of the laparoscopic group were comparable with those of the open surgery group or were partly favorable. The five-year disease-free interval and overall survival of recurrent cancer patients were not significantly different from those of the open patients. Metachronous colorectal cancer occurred in 13 patients (0.38%), 5 of whom had open surgery and 6 had laparoscopic salvage. The only significant difference between the groups was a shorter operating time for the laparoscopic group. Late in the study, four patients in the laparoscopic recurrent group and one patient in the metachronous group were converted to open surgery.
Laparoscopic surgery yielded short-term outcomes that were comparable to those of conventional open surgery, in both recurrent and metachronous colorectal cancer patients. Thus, minimally invasive salvage approaches should be considered as a treatment option for the recurrent and the metachronous colorectal cancer patient.
[Show abstract][Hide abstract] ABSTRACT: To evaluate the technical feasibility, safety, and oncological outcomes of laparoscopic extended lateral pelvic lymph node dissection (LPLD) following total mesorectal excision (TME) in patients with advanced low rectal cancer.
A review of a prospectively collected database at Kyungpook National University Hospital from May 2003 to September 2009 revealed a series of 16 consecutive laparoscopic TME with LPLD patients with preoperative diagnosis of lateral node metastasis. Data regarding patient demographics, operating time, perioperative blood loss, surgical morbidity, lateral lymph node status, functional outcome, and mid-term oncologic result were analyzed.
In all 16 patients, the procedures were completed without conversion to open surgery. During the study period, robot-assisted laparoscopic LPLD was performed in two patients. Mean operative time was 321.9 min (range 220-510 min). The mean number of lateral lymph nodes harvested was 9.1 (range 3-19), and a total of nine patients (56.2%) had lymph node metastases. Postoperative mortality and morbidity were 0 and 31.2%, respectively. Recovery after the procedure was rapid, and mean hospital stay was 9.9 days (range 7-14 days). With median follow-up of 38 months, among nine patients who were lateral pelvic node positive, one patient experienced pelvic side-wall local recurrence (11.2%).
Laparoscopic TME with LPLD is safe and feasible, with the advantage of a minimally invasive approach. Prospective controlled study comparing laparoscopy and conventional open surgery with long-term follow-up evaluation is needed to confirm the authors' initial experience.
[Show abstract][Hide abstract] ABSTRACT: This case-control study compared the clinical outcomes of totally laparoscopic hemicolectomy with natural orifice specimen extraction (NOSE) and the conventional laparoscopically assisted approach for right-sided colonic cancer.
Consecutive patients who underwent totally laparoscopic mobilization of the right colon with transvaginal resection, anastomosis and specimen extraction between April 2007 and December 2009 were matched by various clinicopathological characteristics with patients who had conventional laparoscopically assisted procedures.
Thirty-four patients in each group were studied. The number of lymph nodes harvested and the resection margin status were similar in the two groups. After NOSE, patients experienced less pain (mean(s.e.m.) pain score on day 1: 4·2(0·3) versus 5·7(0·3), P = 0·001; on day 3: 2·6(0·2) versus 3·5(0·2), P = 0·010) and had a shorter hospital stay (mean(s.d.) 7·9(0·8) versus 8·8(1·5) days; P = 0·003). The NOSE group had less surgical morbidity than the laparoscopically assisted group, but the difference was not significant (4 of 34 versus 9 of 34; P = 0·119). After a median follow-up of 23 (range 5-40) months, there was no transvaginal access-site recurrence or posterior colpotomy-related complications. NOSE was associated with significantly better cosmetic results (mean(s.d.) score 7·5(1·7) versus 6·6(1·8); P = 0·037).
The NOSE approach is feasible with favourable short-term surgical outcomes.
British Journal of Surgery 05/2011; 98(5):710-5. DOI:10.1002/bjs.7419 · 5.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In recent years, robot-assisted surgery using the da Vinci System® has been proposed as an alternative to traditional open or laparoscopic procedures. The aim of this study was to compare the short-term outcomes for open, laparoscopic, and robot-assisted rectal resection for cancer.
Two hundred sixty-three patients with rectal cancer who underwent curative resection between 2007 and 2009 were included. Patients were classified into an open surgery group (OS, n = 88), a laparoscopic surgery group (LAP, n = 123), and a robot-assisted group (RAP, n = 52). Data analyzed include operating time, length of recovery, methods of specimen extraction, quality of total mesorectal excision, and morbidity.
The mean operating time was 233.8 ± 59.2 min for the OS group, 158.1 ± 49.2 min for the LAP group, and 232.6 ± 52.4 min for the RAP group (p < 0.001). Patients from the LAP and RAP groups recovered significantly faster than did those from the OS group (p < 0.05). The proportion of operations performed through a natural orifice (intracorporeal anastomosis with transanal or transvaginal retrieval of specimens) was significantly higher in the RAP group (p < 0.001). The specimen quality--with a distal resection margin, harvested lymph nodes, and circumferential margin--did not differ among the three groups. The overall complication rates were 20.5, 12.2, and 19.2% in the OS, LAP, and RAP groups, respectively (p = 0.229).
RAP and LAP reproduce the equivalent short-term results of standard OS while providing the advantages of minimal access. For the experienced laparoscopic colorectal oncologist, use of the da Vinci robot resulted in no significant short-term clinical benefit over the conventional laparoscopic approach.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study is to compare short-term outcomes and surgical quality of robot-assisted (RAP) and laparoscopic (LAP) total mesorectal excision (TME) in patients with low rectal cancer.
From December 2007 to June 2009, 41 consecutive patients with low rectal cancer underwent TME by robot-assisted procedures. The lowest tumor margins were below peritoneal reflection and 1.0-8.0 cm above the anal verge. These patients were matched 1:2 by age, gender, body mass index, date of surgery, American Society of Anesthesiologists score, and tumor stage, with 82 patients who underwent conventional LAP. Macroscopic quality of the specimens and operative and postoperative outcomes were compared.
Mean operation time was 168.0 ± 49.3 min for LAP group and 231.9 ± 61.4 min for RAP group (P < 0.001). Time to regular diet (RAP, 6.7 days vs. LAP, 6.6 days) and length of stay (RAP, 9.9 days vs. LAP, 9.4 days) were similar. The proportion of surgeries performed with the modified natural orifice techniques (totally intracorporeal procedures with transanal or transvaginal retrieval of specimens) was significantly higher in the RAP group (RAP, 48.8% vs. LAP, 13.4%; P < 0.001). There were no between-group differences in specimen quality, including distal resection margins, harvested lymph nodes, and circumferential margins. The overall major complication rates were similar (RAP, 9.8% vs. LAP, 7.3%; P = 0.641).
RAP was safe and effective for patients with low rectal cancer. Furthermore, the technical advantages of robot surgical systems may allow a novel approach using hybrid natural orifice surgery.
[Show abstract][Hide abstract] ABSTRACT: The goal of this study is to evaluate the technical feasibility, safety, and clinical outcomes of totally laparoscopic colectomy with transvaginal anastomosis and extraction of specimen in female patients with right-sided colon cancer.
A review of prospectively collected database at the Kyungpook National University Hospital from April 2007 to December 2007 revealed a series of 14 consecutive patients affected by right colon cancer were operated by use of the totally laparoscopic colectomy with transvaginal anastomosis and extraction of specimen approach. For this approach, the bowel was fully mobilized and a D3 lymphadenectomy was performed with established laparoscopic technique, followed by transvaginal anastomosis and removal of the resected specimen. Data regarding clinicopathological outcomes, surgical morbidity, and short-term oncologic results were analyzed.
No case required an open conversion, but in 2 patients the planned transvaginal retrieval of the specimen was aborted because of inadequate posterior colpotomy. The median operative time was 150.0 minutes (range, 110-330 min) and the median blood loss was 50.0 mL (range, 20.0-115 mL). The median tumor size was 4.0 cm and the number of harvested lymph nodes was 36.0 (range, 13-65). There was no surgical mortality or major morbidity, except one case of postoperative ileus that was conservatively managed. No patient experienced complications directly associated the transvaginal approach; nor did any patient have infection or prolonged spotting from the extraction site postoperatively. Recovery after the procedure was rapid and the median hospital stay was 7.0 days (range, 6-12 d). With a median follow-up 34 months, one patient experienced distant metastasis (7.1%).
In selected cases, totally laparoscopic colectomy with transvaginal anastomosis and extraction of specimen is feasible and reproducible and may be an alternative technique for treatment of women with right colon cancer. This approach may provide both an attractive way to increase patient comfort and a bridge to "pure" natural orifice colon surgery.
Diseases of the Colon & Rectum 11/2010; 53(11):1473-9. DOI:10.1007/DCR.0b013e3181f1cc17 · 3.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Microsatellite instability (MSI) is a molecular marker that can provide valuable prognostic information for colorectal cancer (CRC). However, the predictive role of the MSI status remains less clear than its role in prognostication due to mixed results from previous studies. Therefore, this study investigated the usefulness of the MSI status as a predictive factor for stage II or III CRC patients who received adjuvant doxifluridine therapy. Among 3030 patients with CRC who underwent surgical resection between 1997 and 2006, 564 patients were diagnosed with stage II or III, and adjuvant doxifluridine therapy was administered to 394 patients (70.0%). The MSI status was assessed using the markers BAT25 and BAT26, and samples with instability at both markers were scored as exhibiting high-frequency MSI (MSI-H). Among the 564 patients, 290 patients (51.4%) had stage II, and MSI-H was found in 41 patients (7.3%). With a median follow-up duration of 35.1 months (range, 0.5-135.2), the 5-year overall survival (OS) rate and relapse-free survival (RFS) rate were 87.5 and 76.2%, respectively. MSI-H showed a favorable survival trend for OS (P = 0.098) and significant survival benefit for RFS (P = 0.037) in all patients. In a univariate analysis, the doxifluridine-treated patients with MSI-H showed improved RFS compared to those with low or stable MSI (MSI-L/S) (P = 0.036), while the MSI status was not significantly associated with OS (P = 0.107). In a multivariate analysis, MSI-H was not significantly associated with RFS (Hazard ratio = 2.467, P = 0.125). In conclusion, this study confirmed the positive prognostic role of MSI-H. However, MSI-H patients with stage II or III CRC did not seem to benefit from doxifluridine adjuvant therapy.
[Show abstract][Hide abstract] ABSTRACT: Prior studies suggest that obesity is inversely associated with tumor marker concentration and may reduce diagnostic precision. This study was undertaken to evaluate the association between body mass index (BMI) and serum carcinoembryonic antigen (CEA) concentrations in colorectal cancer patients.
We analyzed the association between BMI and CEA concentration in a group of 2,845 patients who underwent surgical treatment for colorectal adenocarcinoma from 1995 to 2009. Multivariate linear regression analysis was applied to adjust for clinicopathologic confounding factors to analyze main outcome measures. The association of BMI with plasma volume, CEA concentration, and total circulating CEA mass was assessed by determining P values for trends. We also developed a regression formula to calculate the effect of obesity on the serum CEA levels.
Increased BMI was linearly correlated with higher plasma volume (P < 0.001 for trend) and lower adjusted CEA concentrations after controlling for potentially confounding factors (P ≤ 0.005 for trend in stage II and III tumors). Our theoretical model suggests that a CEA value of 7.0 ng/mL in patients of normal weight corresponds to 6.1 ng/mL in obese patients.
The hemodilution effect from increased plasma volume may account for the decreased CEA concentrations observed in patients with higher BMI.
Obesity might be one of the factors that affect CEA value, leading to loss of sensitivity and diagnostic accuracy in the CEA test. The BMI status of patients should be taken into account during assessment of serum CEA during the surveillance of colorectal cancer.
[Show abstract][Hide abstract] ABSTRACT: Peritoneal recurrence after curative resection of colorectal cancer has been considered to be a lethal condition and to be suitable for palliative chemotherapy. Recently, aggressive approaches such as cytoreductive surgery and perioperative intraperitoneal chemotherapy were introduced for peritoneal malignancies to improve survival. The aim of this study is to identify the risk factors of peritoneal recurrence after curative resection of colorectal cancer and to determine the indication of early postoperative intraperitoneal chemotherapy (EPIC).
Journal of the Korean Surgical Society 01/2010; 79(5):355. DOI:10.4174/jkss.2010.79.5.355 · 0.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: CA19-9 was evaluated as a prognostic marker for colorectal cancer and whether it could be helpful in addition to surveillance using CEA was also tested.
Serum CA19-9 levels were measured preoperatively in 1109 patients and monitored at 3-month intervals for the first 2 years postoperatively, and at 6-month intervals thereafter in 700 patients.
Preoperative high CA19-9 was independent prognostic factor for recurrence. Among patients with recurrence, 21.4% had a high postoperative CA19-9. High postoperative CA 19-9 levels were more likely in patients with high preoperative levels. Postoperative CA19-9 increased more in patients with a peritoneal recurrence than in those with liver metastasis (p=0.002). Among patients with recurrence, CA19-9 increased in 7.8% of the patients with a normal follow-up CEA.
Postoperative CA19-9 was more frequently elevated when peritoneal recurrence occurred. Data on CA19-9 levels provided 7.8% of additional information in predicting recurrence in this study.
Anticancer research 10/2009; 29(10):4303-8. · 1.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We assessed which classification of lymph node metastasis better predicted outcomes in patients with colorectal carcinoma.
We identified 318 patients (176 men) with stage III colon cancer who underwent curative resection. The number of LNs dissected, LNR, and disease-free survival time, were analyzed. Lymph node disease was stratified by the American Joint Committee on Cancer staging and LNR, with the latter categorized into groups with LNR <0.059 (n = 67), 0.059-0.23 (n = 171), and >0.23 (n = 80). Median follow-up time was 37 (range, 1-122) months.
LNR significantly increased with the number of metastatic LNs (P < 0.0001). Three-year disease-free survival (DFS) rates differed significantly in the three LNR groups. Within each TNM stage, 3-year DFS rates differed according to LNR, but, within each LNR subgroup, 3-year DFS did not differ according to TNM stage. When both TNM stage and LNR subgroup were considered, 3-year DFS was stratified into four groups, which differed significantly (P < 0.0001). Considering number of retrieved lymph nodes, this stratification was not found when <12 lymph nodes retrieved.
Re-stratified lymph node staging, reflecting both LNR and TNM stage, can predict survival in patients with LN-positive colon cancer, especially when more than 12 lymph nodes harvested.
[Show abstract][Hide abstract] ABSTRACT: We evaluated preoperative serum carcinoembryonic antigen (CEA) as a prognostic factor for colorectal cancer and determined when surveillance of this marker was useful.
Serum CEA was measured preoperatively in 1,263 patients who underwent curative resection for colorectal cancer at 3-month intervals for the first 2 postoperative years and at 6-month intervals thereafter. Mean follow-up was 48 months (range 1-156 months).
The 5-year disease-free survival was less in patients with a high preoperative serum CEA level (P<0.0001). Among patients with a tumor recurrence, 38.5% had high follow-up serum CEA levels. The number of patients with high postoperative serum CEA levels exceeded the number of patients with high preoperative levels. High preoperative and follow-up serum CEA levels were independent prognostic factors for tumor recurrence (P=0.003 and P<0.001, respectively). In patients with high preoperative serum CEA levels, CEA surveillance had a 92.3% positive predictive value (PPV) and a 96.1% negative predictive value (NPV). The mean interval between postoperative serum CEA elevation and the diagnosis of a tumor recurrence [diagnostic interval (DI)] was 2.5 months (range 5-17 months). The DI was 0 in 18.8% of patients with a tumor recurrence.
High serum CEA levels preoperatively and at follow-up are prognostic factors for colorectal cancer. Postoperative serum CEA surveillance is used most effectively when patients have high preoperative serum CEA levels. Considering the DI of 0 in 18.8% of the patients, the current CEA surveillance schedule might be changed.