Wen-Yih Liang

Curative Resection of T1 Colorectal Carcinoma: Risk of Lymph Node Metastasis and Long-Term Prognosis

PURPOSEThe features of T1 colorectal adenocarcinoma and the risk determination of lymph node metastasis were reviewed. Prognostic factors were assessed to verify whether the risk of lymph node metastasis would influence the long-term prognosis.METHODSPatients undergoing curative resection of T1 colorectal adenocarcinoma at the Taipei Veterans General Hospital from December 1969 to August 2002 were retrospectively studied. Patients with synchronous colorectal cancer, distant metastasis, familiar adenomatous polyposis, or inflammatory bowel disease were excluded. The associations between lymph node metastasis and clinicopathologic variables were evaluated univariately using chi-squared test, Fisher’s exact test, or Student’s t -test, and multivariately using logistic regression. Univariate analysis by the log-rank test and multivariate analysis by Cox regression hazards model determined the factors influencing the overall survival.RESULTSA total of 159 patients were included. Sixteen patients (10.1 percent) had lymph node metastasis. The risk of lymph node metastasis included histologic grade (P = 0.005), lymphatic vessel invasion (P = 0.023), inflammation around cancer (P = 0.049), and budding at the invasive front of tumor (P = 0.022). Age (P = 0.001) and number of total sampling lymph nodes (P < 0.0001) were found to be the factors influencing the overall survival.CONCLUSIONSVariables that predict lymph node metastasis in surgically resected T1 colorectal carcinoma may not impact the long-term prognosis.

A 35-year retrospective study of carcinoid tumors in Taiwan: differences in distribution with a high probability of associated second primary malignancies.

A comprehensive study of carcinoid tumors from United States‐based databases indicated that the small intestine, colon, rectum, and bronchopulmonary system are common locations for carcinoid tumors. In addition, certain carcinoid tumors, such as rectal carcinoids, appeared to be overrepresented in nonwhite populations in the United States. High frequencies of associated noncarcinoid malignancies were reported in some articles. The objective of the current study was to address the organ distribution, frequency of metastasis, and survival rates of carcinoid tumors and the associated noncarcinoid tumors in Taiwanese, Asian populations.

Analysis of the seventh edition of American Joint Committee on colon cancer staging

PurposeThe seventh edition of the American Joint Committee on Cancer (AJCC) staging system has new substages for colon cancer. We used survival data from a single medical center to analyze this new AJCC edition.MethodsThe colon cancer database of Taipei Veterans General Hospital provided 1,865 patient records covering from 1999 to 2005. Survival rates were evaluated using the Kaplan–Meier method.ResultsThere were 268, 607, 561, and 421 patients in stages I, II, III, and IV disease with 5-year observed survival rates of 86.3%, 79.2%, 65.4%, and 12.8%, respectively. Survival rates were not significantly different between those with T4a and T4b disease (P = 0.806). The outcome of N1c disease was similar to N1a and N1b but worse than N0 (P = 0.004). Survival rates for M1a and M1b disease became different after reclassifying solely peritoneal seeding as M1a (P < 0.001). No discrepancy of outcomes between stage IIIA and stage IIB/IIC remained in the seventh edition.ConclusionsEvolution from the fifth to seventh edition of the AJCC staging system is successful in separating prognostic groups by substaging. But some issues remain unresolved, including the subdivision of T4, N1, and M1.

Carcinoembryonic antigen (CEA) level, CEA ratio, and treatment outcome of rectal cancer patients receiving pre-operative chemoradiation and surgery

BackgroundTo investigate serum carcinoembryonic antigen (CEA) as a prognostic factor for rectal cancer patients receiving pre-operative chemoradiotherapy (CRT).MethodsBetween 2000 and 2009, 138 patients with advanced rectal cancer receiving CRT before surgery at our hospital were retrospectively classified into 3 groups: pre-CRT CEA <6 ng/ml (group L; n = 87); pre-CRT CEA ≥ 6 ng/ml and post-CRT CEA <6 ng/ml (group H-L; n = 32); and both pre- and post-CRT CEA ≥ 6 ng/ml (group H-H; n = 19). CEA ratio (defined as post-CRT CEA divided by pre-CRT CEA), post-CRT CEA level and other factors were reviewed for prediction of pathologic complete response (pCR).ResultsFive-year disease-free survival (DFS) was better in groups L (69.0%) and H-L (74.5%) than in group H-H (44.9%) (p = 0.024). Pathologic complete response was observed in 19.5%, 21.9% and 5.3% of groups L, H-L and H-H respectively (p = 0.281). Multivariate analysis showed that ypN stage and pCR were independent prognostic factors for DFS and that post-CRT CEA level was independently predictive of pCR. As a whole, post-CRT CEA <2.61 ng/ml predicted pCR (sensitivity 76.0%; specificity 58.4%). For those with pre-CRT CEA ≥6 ng/ml, post-CRT CEA and CEA ratio both predicted pCR (sensitivity 87.5%, specificity 76.7%).ConclusionsIn patients with pre-CRT serum CEA ≥6 ng/ml, those with “normalized” CEA levels after CRT may have similar DFS to those with “normal” (<6 ng/ml) pre-CRT values. Post-CRT CEA level is a predictor for pCR, especially in those with pre-CRT CEA ≥6 ng/ml.

Differences in clinicopathological characteristics of colorectal cancer between younger and elderly patients: an analysis of 322 patients from a single institution

BACKGROUND The prognosis of patients with colorectal cancer (CRC) of different onset ages is controversial. METHODS Data were obtained from a prospective database at Taipei Veterans General Hospital. There were 2,738 newly diagnosed patients with CRC from 2001 to 2006. Two extreme age groups, younger (≤40 years) and elderly (≥80 years), were analyzed to compare clinicopathologic characteristics and prognosis after exclusion of specific cancer syndrome. RESULTS A total of 322 patients were enrolled in this prospective study. The younger group consisted of 69 patients with mean age of 33.5 years, and the elderly group consisted of 253 patients with mean age of 83.4 years. Younger patients had a higher incidence of mucinous cell type (14.5% vs 6.3%, P = .05), poorly differentiated adenocarcinoma (26.1% vs 6.3%, P < .001), more advanced disease (82.6% vs 41.9%, P < .001), poorer disease-free survival (67.2% vs 79.3%, P = .048), and cancer-specific survival (44.1% vs 73.1%, P < .001) than elderly patients. CONCLUSIONS In patients with CRC of younger onset, without relevant predisposing risk factors, younger patients have more advanced stages of disease, more aggressive histopathologic characteristics, and poorer prognoses compared with older patients.

Clinicopathologic features and prognostic analysis of MSI-high colon cancer

PurposeThe objectives of the study were to estimate the incidence and clarify the clinicopathologic feature of sporadic microsatellite instability (MSI)-high (MSI-H) colon cancer. Furthermore, the role of MSI in colon cancer prognosis was also investigated.MethodsMicrosatellite status was identified by genotyping. The clinicopathologic differences between two groups (MSI-H vs. MSI-L/S) and the prognostic value of MSI were analyzed.ResultsFrom 1993 to 2006, 709 sporadic colon cancer patients were enrolled. MSI-H colon cancers showed significant association with poorly differentiated (28.3% vs. 7.2%, p = 0.001), proximally located (76.7% vs. 34.5%, p = 0.001), more high mucin-containing tumor (10.0% vs. 5.1%, p = 0.001) and female predominance (56.7% vs. 30.2%, p = 0.001). In multivariate analysis, MSI-H is an independent factor for better overall survival (HR, 0.459; 95% CI, 0.241–0.872, p = 0.017).ConclusionsBased on the hospital-based study, MSI-H colon cancers demonstrated distinguished clinicopathologic features from MSI-L/S colon cancers. MSI-H is an independent favorable prognostic factor for overall survival in colon cancer.

Taiwan hospital-based detection of Lynch syndrome distinguishes 2 types of microsatellite instabilities in colorectal cancers

BACKGROUND With progress in techniques of molecular biology, the phenotypes and genotypes for Lynch syndrome are more diverse than thought previously. This hospital-based study estimated the incidence and molecular and clinicopathologic features of Lynch syndrome to modify the screening criteria for Taiwanese patients with colorectal cancer (CRC). METHODS A total of 561 CRC patients were enrolled. DNA was extracted from neoplasms, normal mucosa, and/or white blood cells for analyses of microsatellite instability (MSI), BRAF mutation, MLH1 methylation, and sequencing of MMR genes. Immunohistochemistry (IHC) staining for MMR proteins was done for cases that fulfilled revised Bethesda criteria and for high-frequency microsatellite instability (MSI-H) neoplasms. RESULTS There were 136 (24.2%) and 10 (1.8%) cases that fulfilled the Revised Bethesda and Amsterdam II criteria (ACII), respectively. MSI-H was detected in 41 (7.3%), of which 32 showed abnormalities for > or = 1 MMR protein by IHC; low-frequency MSI (MSI-L) or microsatellite stable showed abnormal MSH2 staining in only 1 of 117 neoplasms. Thirteen (2.3%) cases had mutations in MMR genes with MLH1 (n = 10), MSH2 (n = 2), or MSH6 (n = 1). Of 13 Lynch syndrome cases, 3 (23.1%) and 11 (84.6%) fulfilled ACII and revised Bethesda criteria, respectively; 12 cases (93.3%) were MSI-H, and all had expression loss of > or = 1 MMR protein. Eight patients were >50 years old, 2 of whom did not fulfill revised Bethesda criteria. For MSI-H neoplasms without definite mutations, 72.4% and 44.8% showed MLH1 methylation and a BRAF (V599E) mutation, respectively. Lynch-associated CRC and sporadic MSI neoplasms shared similar clinicopathologic features. CONCLUSION In Taiwan, the incidence of Lynch syndrome was 2.3% among the 561 CRC patients evaluated. For Taiwanese CRC patients who are younger than age 60 whether or not fulfilling the Bethesda criteria should receive MSI or IHC screening for identification of the Lynch syndrome.

Surgical resection combined with chemotherapy can help achieve better outcomes in patients with primary colonic lymphoma.

The colon is a rare location for gastrointestinal non‐Hodgkins lymphoma. We retrospectively analyzed the demographic data of patients with colonic lymphoma and the possible prognostic factors of the disease.

Circumferential margin plays an independent impact on the outcome of rectal cancer patients receiving curative total mesorectal excision

BACKGROUND The aim of this study was to determine the impact of the circumferential resection margin on the outcomes of patients with rectal cancer undergoing total mesorectal excision. METHODS Medical records from July 2004 to June 2008 were prospectively reviewed, and 348 patients who underwent potentially curative surgery for rectal cancer were identified. The influence of the circumferential resection margin on local recurrence, distant metastasis, and 5-year cancer-specific survival was assessed. RESULTS Of 348 patients, 13 (3.7%) had positive circumferential resection margins. During a median follow-up period of 58.0 months, 8 patients (2.3%) had local recurrence and 53 (15.2%) developed distant metastases. Local recurrence rates and distant metastasis rates in patients with positive circumferential resection margins were 15.4% and 61.5%, respectively, significantly higher than in those with negative circumferential resection margins (1.8% and 13.4%, respectively) (P < .001). The 5-year cancer-specific survival rates were 75.8% and 0% for patients with tumors having negative and positive circumferential resection margins, respectively (P < .001). CONCLUSIONS A circumferential resection margin of ≤1 mm adversely affects cancer-specific survival, local recurrence, and distant metastasis.

A 20-year retrospective study of small-cell carcinomas in Taiwan

Small‐cell carcinomas (SCC) develop most commonly in the lung (small‐cell lung carcinoma, SCLC) and only small percentages are present at extra‐pulmonary sites. This study aimed to examine the distribution, treatment, and survival of SCCs.