Chien-Yuh Yeh

Evaluation of Prognosis for Malignant Rectal Gastrointestinal Stromal Tumor by Clinical Parameters and Immunohistochemical Staining

PURPOSEThe aim of this study was to identify associated prognostic factors influencing the outcome of curative resection of rectal gastrointestinal stromal tumor.PATIENTS AND METHODSDiagnostic immunohistochemical staining with CD34, CD117, S-100, desmin, and muscle-specific actin was performed in 46 consecutive patients with previously diagnosed rectal leiomyosarcoma who underwent curative resection from 1979 to 1999. CD44, Bcl-2, P53, and Ki-67 staining were performed on tumors rediagnosed as gastrointestinal stromal tumor for the prognostic evaluation.RESULTSThere were 42 (91.3 percent) patients with rectal gastrointestinal stromal tumor (18 females and 24 males; mean age, 58.4 years). Twenty-nine patients underwent radical surgical resections, such as abdominoperineal resection or low anterior resection, whereas the other 13 patients underwent wide local excision, such as transrectal excision or Kraske’s operation. Sixteen tumors were classified as high-grade gastrointestinal stromal tumors, and 26 as low-grade. No tumor had a positive P53 stain. Twenty-seven patients (64.3 percent) developed recurrence or metastasis postoperatively (median follow-up, 52 months). The one-year, two-year, and five-year disease-free survival rates were 90.2 percent, 76.7 percent, and 43.9 percent, respectively. Of these patients with recurrence, subsequent resections in 12 patients with local recurrence, transarterial tumor embolism or STI-571 chemotherapies in 3 patients with distant mestastases were performed. The one-year, two-year, and five-year overall survival rates were 97.4 percent, 94.3 percent, and 83.7 percent, respectively. Bcl-2 (P = 0.007) and histologic grade (P = 0.05) in disease-free survival analysis and age <50 years (P = 0.03) and tumor size >5 cm (P = 0.02) in overall survival analysis were independent prognostic factors. The group with wide local excision had a higher local recurrence rate than that of the radical resection group (77 percent vs. 31 percent, P = 0.006), despite smaller tumors (4.5 vs. 7.2 cm, P = 0.05). There was no difference in the incidence of distant metastasis between the two groups.CONCLUSIONYounger age (<50 years), higher histologic tumor grade, positive Bcl-2 status, and larger tumors (>5 cm) were factors associated with significantly poorer prognoses for rectal gastrointestinal stromal tumor. Radical resection was superior to wide local excision in the prevention of local recurrence, but not that of distant metastases.

The oncologic benefit of high ligation of the inferior mesenteric artery in the surgical treatment of rectal or sigmoid colon cancer

PurposeIt remains controversial as to whether high ligation of the inferior mesenteric artery (IMA) should be performed during surgical treatment for sigmoid colon or rectal cancer. The purpose of this study is to attempt to clarify the extent of the oncologic benefit of high ligation of the IMA.Materials and methodsFrom January 1995 to July 2001, a total of 1,389 patients underwent high ligation of the IMA; 387 patients featured non-disseminated sigmoid colon cancer and 1,002 patients had rectal cancer. Pathology of the primary tumors, IMA nodes, and clinical outcome were reviewed.ResultsForty-three patients (3.1%) revealed IMA node metastasis. Of these 43 patients, 29 (67.4%) featured tumor recurrences/metastases. After a minimum 5-year follow-up, 11 of these 43 patients (25.6%) were alive and disease free. Of these 43 patients, the 5-year disease-free survival rate for patients featuring sigmoid cancer was 50% and for patients with rectal cancer 13.8%. The beneficial rate of high ligation of the IMA for non-disseminated sigmoid colon cancer and rectal cancer was 0.8%, for non-disseminated sigmoid colon cancer 1.8%, and for non-disseminated rectal cancer, the rate was only 0.4%. The rates of IMA metastasis in patients with T stage tumors were 0% (pT1), 1.0% (pT2), 2.6% (pT3), and 4.3% (pT4).ConclusionsAlthough patients afflicted with IMA node metastasis revealed a rather high incidence of tumor recurrence/metastasis, 25.6% of these patients remained disease free following IMA node dissection after a minimum 5-year follow-up. We consider that IMA node dissection is more beneficial in patients with non-disseminated sigmoid pT4 tumor.

Metastatic lymph node ratio is a more precise predictor of prognosis than number of lymph node metastases in stage III colon cancer

ObjectiveThe objective of this study is to assess the value of metastatic lymph node ratio (LNR) in predicting disease-free survival (DFS) in patients with stage III adenocarcinoma of the colon.Materials and methodsFrom 1995 to 2003 inclusively, a total of 624 patients featuring stage III adenocarcinoma of the colon underwent curative resection. Of the 624 patients, an adequate number of lymph nodes (n ≥ 12) had been harvested in 490 patients. These patients were stratified into LNR groups 1 (LNR ≤ 0.4), 2 (0.4 < LNR ≤ 0.7), and 3 (LNR > 0.7). Kaplan–Meier survival curve and log-rank test were used to evaluate the prognostic value of LNR. A Cox regression model was used for multivariate analyses.ResultsThe 5-year DFS rate was 66.7% for patients with LNR1, 35.1% for those with LNR2, and 0% for patients with LNR3 (p < 0.0001). In T3/4LNR1 patients (n = 411), there was no difference in survival between those with N1 stage and those with N2 stage. Cox proportional hazards regression analysis revealed that N stage (number of positive lymph nodes) was not a significant factor when LNR was taken into consideration.ConclusionsLNR is a more precise predictor of 5-year DFS than number of positive lymph nodes (N stage) in patients with stage III colon cancer.

Circulating Tumor Cell Count Correlates with Colorectal Neoplasm Progression and Is a Prognostic Marker for Distant Metastasis in Non-Metastatic Patients

Enumeration of circulating tumor cells (CTCs) has been proven as a prognostic marker for metastatic colorectal cancer (m-CRC) patients. However, the currently available techniques for capturing and enumerating CTCs lack of required sensitivity to be applicable as a prognostic marker for non-metastatic patients as CTCs are even more rare. We have developed a microfluidic device utilizing antibody-conjugated non-fouling coating to eliminate nonspecific binding and to promote the multivalent binding of target cells. We then established the correlation of CTC counts and neoplasm progression through applying this platform to capture and enumerate CTCs in 2 mL of peripheral blood from healthy (n = 27), benign (n = 21), non-metastatic (n = 95), and m-CRC (n = 15) patients. The results showed that the CTC counts progressed from 0, 1, 5, to 36. Importantly, after 2-year follow-up on the non-metastatic CRC patients, we found that those who had ≥5 CTCs were 8 times more likely to develop distant metastasis within one year after curable surgery than those who had <5. In conclusion, by employing a sensitive device, CTC counts show good correlation with colorectal neoplasm, thus CTC may be as a simple, independent prognostic marker for the non-metastatic CRC patients who are at high risk of early recurrence.

Stapled colonic J-pouch-anal anastomosis without a diverting colostomy for rectal carcinoma

PURPOSE: Colonic J-pouch reconstruction is designed to improve functional outcome of coloanal anastomosis. Most surgeons use a diverting colostomy to avoid severe pelvic sepsis caused by anastomotic breakdown. METHODS: We report the outcome of 30 consecutive patients with colonic J-pouch-anal anastomosis without a diverting colostomy performed between November 1992 and October 1993. All patients had carcinoma of the lower two-thirds of the rectum. Patients were seen every three months. Functional results were compared with those of 21 rectal cancer patients with straight coloanal anastomosis who underwent surgery in the same period and 20 normal patients. RESULTS: There were two anastomotic leakages and one postoperative death. After one year, patients with pouch anastomosis had significantly less frequency of defecation and rectal urgency compared with those with straight anastomosis (P<0.01); 48 percent of patients with straight anastomosis had more than five bowel movements per day, whereas all patients with pouch anastomosis had five or less bowel movements per day. Manometric studies showed maximum tolerable volume was significantly higher in patients with pouch anastomosis (81vs.152 ml;P<0.01). CONCLUSIONS: Stapled colonic J-pouch-anal anastomosis without a diverting colostomy is a reliable procedure that provides good, long-term functional results.

Effect of Body Mass Index on the Outcome of Patients With Rectal Cancer Receiving Curative Anterior Resection: Disparity Between the Upper and Lower Rectum

Objective:The aim of this study was to investigate the effect of body mass index (BMI) on local recurrence of primary rectal cancer after open curative sphincter-saving resection. Background:Increasing BMI was reported to be associated with a higher likelihood of local recurrence in male patients with rectal cancer. However, it remained unclear whether BMI exerts the same effects on local recurrence of rectal cancer in the upper and lower rectum. Methods:Between January 1995 and December 2002, we investigated 1873 patients with well-documented body height and body weight who underwent curative anterior resection for primary rectal cancer in a single institution. The patients were assigned to 4 groups according to their BMI: underweight, normal, overweight, and obese. Results:The frequency of local recurrence increased with an increase in the BMI in patients with lower rectal cancer. The local recurrence rates were 2.5% (2 of 79), 6.1% (48 of 782), 9.2% (39 of 424), and 13.8% (9 of 65) in underweight, normal, overweight, and obese patients with lower rectal cancer, respectively. These results were different from those of patients with upper rectal cancer. Independent risk factors for local recurrence in the lower rectal cancer group were BMI, resection margin, histologic grade of differentiation, depth of tumor invasion, and status of lymph node metastases. In the upper rectal cancer group, the depth of tumor invasion and histologic grade of differentiation reached statistical significance. Conclusions:BMI exerted different effects on local recurrence of rectal cancer in the upper and lower rectum. Further, more aggressive adjuvant and/or neoadjuvant treatments should be considered for patients with tumor in the lower rectum and with higher BMI.

risk Factors Associated With Posthemorrhoidectomy Secondary Hemorrhage : a Single-institution Prospective Study of 4,880 Consecutive Closed Hemorrhoidectomies

AbstractPURPOSE: Posthemorrhoidectomy secondary hemorrhage is a rare but serious complication after hemorrhoidectomy. The determination of risk factors for this complication may provide information to improve outcome. A prospective study was conducted to determine the risk factors associated with posthemorrhoidectomy secondary hemorrhage. METHODS: We studied 4,880 patients who underwent an elective closed hemorrhoidectomy by 9 proctologists in a single institution between January 1994 and July 1996. The variables analyzed included age, gender, surgeon, surgeon’s seniority, suture material, aseptic preparation, and use of antibiotics. The logistic regression model was used to assess the independent association of variables with posthemorrhoidectomy secondary hemorrhage. RESULTS: Among the 4,880 patients, 45 (0.9 percent) developed posthemorrhoidectomy secondary hemorrhage. The mean interval from operation to the onset of secondary hemorrhage was 8.8 (range, 5–19) days. Multivariate analysis revealed that patient’s gender and individual surgeons were both independently associated with risk of hemorrhage. Male patients were more likely than females to develop posthemorrhoidectomy secondary hemorrhage (relative risk, 2.1; 95 percent confidence interval, 1.1–4.1; P = 0.021). The posthemorrhoidectomy secondary hemorrhage rates among individual surgeons ranged from 0.2 to 2.4 percent (P = 0.003). CONCLUSION: Our data suggest that male patients are more likely to develop posthemorrhoidectomy secondary hemorrhage than female patients and that intersurgeon variability is highly correlated with this risk.

Impact of the Cyclin D1 A870G Polymorphism on Susceptibility to Sporadic Colorectal Cancer in Taiwan

PurposeCyclin D1 is a regulatory protein involved in the cell cycle of both normal and neoplastic cells. Polymorphism of this gene at codon 242 in exon 4 has impacts on risk of the early-age onset in several malignant neoplasms, including colorectal cancer. This investigation was designed to evaluate the effect of cyclin D1 gene polymorphism on the risk of colorectal cancer in Chinese migrants of the Taiwanese population.MethodsWe enrolled 831 primary sporadic colorectal cancer patients as the study group and 1,052 age-gender matched healthy individuals as the control group (1,883 total cases) for present study. Cyclin D1 genotypes (AA, AG, GG) were determined using PCR-RFLP analysis on genomic DNA.ResultsThe frequency of G allele was 39.89 percent and 40.96 percent in the study group and the control group, respectively (P = 0.02). The patients were divided into three age groups for statistical analysis. The younger male patients had a higher frequency of AA/AG genotype compared with the controls (odds ratio, 2.75; 95 percent confidence interval, 1–7.9). The effect of AA/AG genotype on colorectal cancer risk was statistically significant for male patients (odds ratio, 1.34; 95 percent confidence interval, 1.04–1.72), but suchphenomenon was not observed in female patients.ConclusionsOur study suggests that the effect of cyclin D1gene polymorphism on colorectal cancer risk is only observed in males and AA/AG genotype of cyclin D1 gene is associated with a higher risk of colorectal cancer in theyounger patients within the Taiwanese population.

Utility of 2-fluoro-2-deoxy-D-glucose positron emission tomography in managing patients of colorectal cancer with unexplained carcinoembryonic antigen elevation at different levels.

PURPOSESerum carcinoembryonic antigen elevation without detectable relapse during colorectal cancer follow-up presents a challenge. This study was designed to evaluate the utility of fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography in colorectal cancer patients with unexplained carcinoembryonic antigen elevation at different levels.METHODSThirty-seven colorectal cancer patients referred for positron emission tomography after primary surgery who had serum carcinoembryonic antigen levels >5 ng/ml and negative or equivocal conventional imaging studies were analyzed. Patient status was determined by histopathology and/or clinical follow-up. Grouping as disease-free, potentially resectable, or advanced disease was performed. The management impact was defined as the percentage of patients with a true-positive positron emission tomography result.RESULTSThe sensitivity, specificity, and accuracy of positron emission tomography for relapse detection were 89, 89, and 89 percent, respectively. The management impact was 68 percent. In 24 patients with carcinoembryonic antigen levels <25 ng/ml, positron emission tomography helped correct patient grouping in 20 patients (83 percent), including 8 in the disease-free group, 5 in the potentially resectable group, and 7 in the advanced-disease group. In 13 patients with carcinoembryonic antigen levels >25 ng/ml, positron emission tomography identified 8 patients in the advanced-disease group and 1 patient in the potentially resectable group but missed 2 patients with relapse and undergrouped 2 patients in the advanced-disease group as potentially resectable.CONCLUSIONS2-fluoro-2-deoxy-D-glucose positron emission tomography can help triage patients for appropriate management with unexplained carcinoembryonic antigen elevation <25 ng/ml. For patients with unexplained elevation of carcinoembryonic antigen >25 ng/ml, the utility of positron emission tomography is mainly to confirm the presence of advanced disease and occasionally to identify potentially resectable lesions.

Role of body mass index in colon cancer patients in Taiwan

AIM To determine the effect of body mass index (BMI) on the characteristics and overall outcome of colon cancer in Taiwan. METHODS From January 1995 to July 2003, 2138 patients with colon cancer were enrolled in this study. BMI categories (in kg/m²) were established according to the classification of the Department of Health of Taiwan. Postoperative morbidities and mortality, and survival analysis including overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS) were compared across the BMI categories. RESULTS There were 164 (7.7%) underweight (BMI < 18.5 kg/m²), 1109 (51.9%) normal-weight (BMI = 18.5-23.9 kg/m²), 550 (25.7%) overweight (BMI = 24.0-26.9 kg/m²), and 315 (14.7%) obese (BMI ≥ 27 kg/m²) patients. Being female, apparently anemic, hypoalbuminemic, and having body weight loss was more likely among underweight patients than among the other patients (P < 0.001). Underweight patients had higher mortality rate (P = 0.007) and lower OS (P < 0.001) and DFS (P = 0.002) than the other patients. OS and DFS did not differ significantly between normal-weight, overweight, and obese patients, while CSS did not differ significantly with the BMI category. CONCLUSION In Taiwan, BMI does not significantly affect colon-CSS. Underweight patients had a higher rate of surgical mortality and a worse OS and DFS than the other patients. Obesity does not predict a worse survival.