Colon cancer mesenchymal stem cells modulate the tumorigenicity of colon cancer through interleukin 6.

Multipotent mesenchymal stem cells (MSCs) have been isolated from several tumors and are implicated to play critical roles to increase malignant cell growth, invasion and metastasis. Here, we show that the MSC-like cells were isolated from human colon cancer tissues. These isolated hCC-MSCs (human colon cancer-derived mesenchymal stem cells) shared similar characteristic features with bone marrow-derived MSCs, which include cell morphology, surface antigens and specific gene expression. Additionally, the hCC-MSCs could differentiate into osteocytes or adipocytes under appropriate culture conditions. The conditioned medium collected from the cultured hCC-MSCs was shown to enhance the migration and invasive activity of HCT-116 colon cancer cells in vitro. Besides, transplantation of HCT-116 cells along with hCC-MSCs in nude mice increased the tumor growth and metastasis. Further study revealed that IL-6 present in the hCC-MSC-conditioned medium sufficiently induced the levels of Notch-1 and CD44 in HCT-116 and HT-29 cells, which contribute to enhance tumorigenic activity of HCT-116 and HT-29 cells. By using immunohistochemical staining, the intense co-expression of IL-6, Notch-1 and CD44 was predominantly detected in human colon cancer tissues. Taken together, our findings suggest the importance of the IL-6/Notch-1/CD44 signaling axis in the interaction between hCC-MSCs and colon cancer cells.

Prognostic significance of the number of tumors and aggressive surgical approach in colorectal cancer hepatic metastasis.

BACKGROUND: Although liver resection (LR) for colorectal cancer (CRC) hepatic metastasis is the best strategy to improve patient outcomes, there are considerable concerns regarding the recurrence of CRC after LR. In this study, we investigated the prognostic indicators associated with CRC recurrence after LR for hepatic metastasis. METHODS: This is a retrospective review of patients who underwent curative LR for CRC hepatic metastasis between January 2008 and December 2012. The clinicopathological features and outcome parameters affecting prognosis were analyzed. RESULTS: A total of 332 LRs with curative intent were performed in 278 patients, of whom 168 (60.4%) experienced CRC recurrence after the first LR, and 206 of the 332 LRs (62.0%) developed CRC recurrence. A preoperative serum carcinoembryonic antigen level greater than 100 ng/mL and four or more metastatic tumor nodules were independent prognostic factors for CRC recurrence after LR. The disease-free survival rate after LR was significantly associated with the number of metastatic nodules. The patients who underwent surgical resection for recurrent CRC had favorable outcomes, with a five-year overall survival rate of 65.2%. CONCLUSION: The number of metastatic tumors significantly affects the outcomes of patients who undergo LR for CRC hepatic metastasis, indicating that a novel therapeutic strategy for patients at high risk may be required. However, favorable long-term outcomes are achievable through aggressive treatment with surgical resection of the recurrent CRC.

An open-label safety study of first-line bevacizumab in combination with standard chemotherapy in Chinese patients with metastatic colorectal cancer treated in an expanded access program in Taiwan.

OBJECTIVE: An increased risk of serious adverse effects related to bevacizumab has been observed in many Western studies for metastatic colorectal cancer. To evaluate the safety of bevacizumab in Chinese patients, a safety study was conducted in Taiwan. METHODS: Bevacizumab was provided by the Expanded Access Program in combination with first-line chemotherapy per investigator's choice. The primary objective is the safety profile, particularly the targeted adverse events such as proteinuria, bowel perforation, hypertension, wound healing complication, thromboembolism and bleeding. The second objectives include time to disease progression and overall survival time. Patients with major surgical procedure performed within the 28 days of bevacizumab were excluded from this study. RESULTS: Forty patients were eligible for intent-to-treat analysis. The overall rate of objective response and disease control was 55.2 and 81.6%. The median time to disease progression and overall survival were 11.9 and 22.9 months. The actuarial 2-year survival was 46.6%. Regarding toxicity, 7 subjects (17.5%) had serious adverse effects related to study treatment. None of the patients in this cohort had arterial thrombotic events and bowel perforation. CONCLUSIONS: Bevacizumab demonstrates a similar activity and safety profile in Chinese patients. Life-threatening bowel complications were avoided in this study by excluding patients with major surgery within the first 28 days.

Impact of chemotherapy-related prognostic factors on long-term survival in patients with stage III colorectal cancer after curative resection.

BACKGROUND: This retrospective study evaluated the prognostic factors of chemotherapy in stage III colorectal cancer after curative resection. METHODS: From 1996 to 2001, 1,054 patients with primary single colorectal cancer underwent curative resection. Seven hundred sixteen patients received various 5-fluorouracil (FU)-based adjuvant chemotherapy regimens, including oral and intravenous treatments. The chemotherapy-related parameters examined included therapeutic duration, frequency, route of administration, composition of combination therapies, and postoperative time interval from the operation to the start of chemotherapy. RESULTS: The therapeutic duration and postoperative time interval of starting therapy were independent prognostic factors, in addition to clinicopathological factors. The 8-year cancer-specific/overall survival rates in patients who received chemotherapy for >4 months (63.0/58.6%) were significantly higher than the rates in patients who received no chemotherapy (56.7/37.7%, P < 0.01) and those who remained on chemotherapy for 1-4 months (49.4/41.9%, P < 0.05). The 8-year cancer-specific/overall survival rates in patients who waited 1-5 weeks after surgery to receive chemotherapy (62.9/58.5%) were significantly higher versus rates in those who did not receive chemotherapy (56.7/37.7%) and those who did not receive chemotherapy until >5 weeks after surgery (52.3/45.9%) (both P < 0.05). Survival rates did not differ between patients who did not undergo chemotherapy, those for whom chemotherapy lasted 1-4 months, and patients who did not receive chemotherapy until >5 weeks after surgery. CONCLUSIONS: The appropriate duration of therapy and early chemotherapy after surgery were 2 of the most important factors in eradicating occult cancer and effecting long-term survival benefits in patients with stage III colorectal cancer.

Concurrent chemoradiotherapy in the treatment of locally recurrent rectal cancer.

BACKGROUND/AIMS: Long course concurrent chemoradiotherapy provides potential tumor downstaging. When local recurrent rectal cancer without distant metastases is diagnosed, a potentially curative resection can be performed. The aim of this study was to assess the outcome of concurrent chemoradiotherapy in treating isolated local recurrent rectal cancer. METHODOLOGY: Patients (n=102) with isolated local recurrent rectal cancer within the pelvis were scheduled for concurrent chemoradiotherapy, consisting of pelvic irradiation with a total dose of 50.4 Gy in 28 fractions. Chemotherapy was administered concurrently and included 85 mg/m2 oxaliplatin by venous infusion over 2 h on day 1, followed by 1,200 mg*m-2*day-1 of continuous venous infusion for 2 days. This regimen was repeated every 2 weeks for 6 cycles. The overall survival rate, responses, disease-free interval and toxicities were assessed. RESULTS: A total of 96 patients completed planned concurrent chemoradiation. Complete clinical responses were found in 13 of the 96 patients (14%), partial responses in 59 (61%), stable disease in 21 (22%) and disease progression in 3 (3%). The overall survival and disease-free survival rates in all the 96 patients were 45% and 14%, respectively. CONCLUSIONS: The treatment of locally recurrent rectal cancer is complicated. Concurrent chemoradiation can increase disease-free survival and overall survival by increasing complete resection rate of locally recurrent tumors and even complete response of the tumors. Ongoing treatment strategies aim to enhance response rates and to accurately assess the extent of local recurrent tumor response to concurrent chemoradiation.

Anorectal melanoma: review of 22 consecutive cases.

BACKGROUND/AIMS: To evaluate outcome and prognostic factors of patients with anorectal melanoma. METHODOLOGY: Twenty-two consecutive patients with anorectal melanoma received operation from 1993 through 2011 were reviewed. The definitions of stage I, II and III are local disease, locoregional lymphadenopathy and metastatic disease, respectively. RESULTS: The patients included 8 men and 14 women, aged from 36 to 83 years (mean, 58.4 years). At the end of the follow-up period, 19 patients died of disease and only 3 patients were alive with disease. Only two patients were alive longer than 5 years after operation. For stage I and II tumors that underwent clinical curative resection (n=17), stage II (p=0.04), tumor size >3 cm (p=0.008) and invasion depth to muscle (p=0.021) all showed poorer prognosis in overall survival. Though wide local excision (WLE) were performed in the patients with earlier tumors, there was no statistical difference in overall (p=0.063) and disease-free survival (p=0.333) between WLE and radical surgery. Furthermore, patients with WLE had more chance of local recurrence than radical surgery (6/7 vs. 3/10, p=0.050). Four salvage radical operations could be performed after local recurrence in WLE group. CONCLUSIONS: WLE increases the chance of local recurrence more than radical surgery. Care should be taken to avoid microseeding during performed WLE.

Proteomic analysis of the effects of baicalein on colorectal cancer cells.

Baicalein is the flavonoids with multiple pharmacological activities. The aim of our study was to investigate the effects of baicalein on colorectal cancer (CRC) and to recognize the targets of baicalein treatment. To better understand baicalein's target, proteomic approaches were used to purify and identify the protein substrates using 2D difference gel electrophoresis (2D SDS-PAGE) to elucidate proteins differential display. Results from this study investigate that baicalein treatment of CRC cells results in reduced cell proliferation. As a result, differential protein displays between baicalein-treated and untreated CRC were determined and validated. There were 11 differentially expressed proteins between baicalein-treated and untreated CRC. Furthermore, we demonstrate that baicalein inhibits cancer cell proliferation and reduced reactive oxygen species (ROS) by up-regulating the levels of peroxiredoxin-6 (PRDX6). Knockdown of PRDX6 in baicalein-treated CRC cells by specific small interfering RNA resulted in ROS production and proliferation, opposite of the baicalein treatment scenario as indicated by cell cycle distribution. These results illustrate that baicalein up-regulates the expression of PRDX6, which attenuates the generation of ROS and inhibits the growth of CRC cells, whereas baicalein treatment have no effect on normal epithelial cells.

Does body mass index impact the number of LNs harvested and influence long-term survival rate in patients with stage III colon cancer?

BACKGROUND: The aim of this study is to evaluate whether different body mass index (BMI) values affect lymph node (LN) retrieval and whether such variations influence long-term survival in Asian patients. METHOD: From January 1995 to July 2003, 645 stage III colon cancer patients were enrolled in our study. Patients were stratified into four groups: Obese (BMI ≧ 27 kg/m(2)), overweight (24 ≤ BMI < 27 kg/m(2)), normal (18.5 ≤ BMI < 24 kg/m(2)), and underweight (BMI < 18.5 kg/m(2)). RESULTS: Mean BMI in the cohort was 23.3 kg/m(2). Mean number of LNs harvested was 23.1, 19.5, 19.8 and 28.1 in the normal, overweight, obese and underweight groups, respectively. There was a significant difference in the mean number of LNs harvested when comparing the overweight and underweight groups to the normal group (p = 0.013 and p = 0.04, respectively). Females were overrepresented in the underweight group (p = 0.011), and patients who had proximal colon cancers were more frequently underweight (p = 0.018). The mean number of LNs harvested varied by cases of right hemicolectomy (p = 0.009) and proximal cancer location (p = 0.009) for different BMI groups. Multivariate analysis showed that underweight, proximal colon cancer, well- or moderately differentiated adenocarcinoma and stage IIIC cancer were significant variables for adequate LN recovery. BMI was not significantly associated with relapse-free survival (p = 0.523) or overall survival (p = 0.127). CONCLUSION: BMI is associated with LN harvest but is not an independent variable in stage III colon cancer survival.

Low preoperative serum albumin in colon cancer: a risk factor for poor outcome.

OBJECTIVE: The number of colon cancer patients is increasing worldwide. Malnutrition and comorbidities are frequently associated with these patients. The relationships between the preoperative malnutrition and the outcomes of colon cancer patients are unclear; this study aimed to clarify these issues. METHODS: A total of 3,849 consecutive colon cancer patients were enrolled in an analysis of short-term outcomes and 2,529 patients were included in an analysis of the long-term outcomes. These patients were divided into the hypoalbuminemic and normal groups according to the definition of hypoalbuminemia (serum albumin < 35 g/L). RESULTS: Advanced age, female gender, abnormal CEA levels, right colon or large tumors, mucinous adenocarcinoma, poor differentiation, stage II cancer, TNM advancing T stage, old cardiovascular accident, diabetes, and liver cirrhosis were more likely to be associated with hypoalbuminemia. Hypoalbuminemic patients had a higher rate of postoperative mortality and morbidity, including complications related to wounds, lungs, the urinary system, and anastomosis. The 5-year overall survival rates of patients with normal albumin and hypoalbuminemia were 78.0% and 60.0%, respectively (P < 0.0001), and the 5-year relapse-free survival rates were 78.9% and 73.5%, respectively (P = 0.0042). In a multivariate analysis, the albumin level was also significantly correlated with 5-year overall survival (<35 vs. ≥ 35, HR 1.75; 95% CI 1.49-2.08) and 5-year relapse-free survival (<35 vs. ≥ 35, HR 1.28; 95% CI 1.04-1.56). CONCLUSIONS: Hypoalbuminemia is a predictor of poor surgical outcomes of colon cancer and is a poor prognosis factor for long-term survival of colon cancer after curative operation.

Long-term survival benefits of adjuvant chemotherapy by decreasing incidence of tumor recurrence without delaying relapse in stage III colorectal cancer.

BACKGROUNDS AND AIMS: To elucidate the survival benefits of adjuvant chemotherapy by decreasing incidence or by delaying time of tumor recurrence, we reported the long-term results of a nonrandomized prospective study comparing the adjuvant chemotherapy to no chemotherapy in stage III colorectal cancer. PATIENTS: From 1991 to 1995, 463 patients with stage III colorectal cancer were divided to three groups which were no chemotherapy, weekly chemotherapy, and monthly chemotherapy (5-FU plus levamisole). RESULTS: The recurrent incidence was significantly decreased in patients with chemotherapy (47.8% vs. 63.9% of no chemotherapy, P = 0.001), resulting into better survival. The 10-year cancer-specific and overall survival rates of patients with chemotherapy vs. no chemotherapy were 52.1% vs. 37.8% and 46.9% vs. 29.9%, respectively (P < 0.001). Weekly chemotherapy had better survival than monthly chemotherapy (P < 0.05). There was no significant difference in recurrent time or types between the patients with and without chemotherapy. The percentages of patients with recurrence happened within 3 years were 85.2% and 84.6% of those with and without chemotherapy, respectively. Patients with advanced stage of T4b invasion depth, N2, and central node invasion had no significant survival benefits by adjuvant chemotherapy. CONCLUSIONS: Long-term survival benefits achieved by adjuvant chemotherapy is through decreasing recurrent incidence, not through postponing tumor recurrent time. That means adjuvant chemotherapy indeed cures some patients by eradicating occult tumor. In adjuvant setting, more powerful regimen for eradicating occult tumor is the keystone to improve long-term survival of stage III colorectal cancer.

Effect of preoperative neutrophil-lymphocyte ratio on the surgical outcomes of stage II colon cancer patients who do not receive adjuvant chemotherapy.

BACKGROUND AND AIMS: Selection of appropriate stage II colon cancer patients for adjuvant chemotherapy is critical for improving survival outcome. With the aim of identifying more high risk factors for stage II colon cancer, this study aimed to determine whether the neutrophil-lymphocyte ratio (NLR) is a predictor of surgical outcomes in patients with stage II colon cancer who do not receive adjuvant chemotherapy. MATERIALS AND METHODS: We enrolled 1,040 stage II colon cancer patients who had undergone colectomy at a single institution between January 1995 and December 2005 and did not receive adjuvant chemotherapy. RESULTS: Of these 1,040 patients, 785 (75.5%) patients had a normal NLR and 255 (24.5%) had an elevated NLR. Those with an elevated NLR included patients ≥65 years, T4b cancer, carcinoembryonic antigen ≥5 ng/mL, and tumor obstruction or perforation. Patients with an elevated NLR had a significantly worse overall survival (OS) and worse disease-free survival (DFS) than did patients with a normal NLR. Cox regression analysis revealed that elevated NLR was an independent predictor of OS (P=0.012) but not DFS (P=0.255). CONCLUSION: An elevated NLR is an independent predictor of OS but not DFS in stage II colon cancer patients who did not receive adjuvant chemotherapy. Preoperative NLR measurement in stage II colon cancer patients may be a simple method for identifying patients with a poor prognosis who can be enrolled in further trials of adjuvant chemotherapy.

Surgical resection of locally advanced primary transverse colon cancer--not a worse outcome in stage II tumor.

BACKGROUND AND AIMS: In locally advanced primary transverse colon cancer, a tumor may cause perforation or invade adjacent organs. Extensive resection is the best choice of treatment, but such procedures must be weighed against the potential survival benefits. This study was performed to identify the clinicopathological features and treatment outcomes of such tumors. MATERIALS AND METHODS: We retrospectively reviewed the database of the Colorectal Cancer Registry of Chang Gung Memorial Hospital between February 1995 and December 2005. Patients with colon cancer sited between the hepatic and splenic flexure that involved an adjacent organ without distant metastasis were defined as having locally advanced transverse colon cancer. RESULTS: A total of 827 patients who underwent surgery for transverse primary colon cancer were enrolled in the study. Stage II and stage III colon cancer were diagnosed in 548 patients. Thirty-two (5.8%) patients were diagnosed with locally advanced tumors. Multivariate analysis revealed that stage III, preoperative carcinoembryonic antigen ≥5 ng/mL, a tumor with perforation or obstruction, and the presence of a locally advanced tumor were significant prognostic factors for both overall and cancer-specific survival. Postoperative morbidity rates differed significantly between the locally advanced and non-locally advanced tumor groups (22.7% vs. 12.3%, P < 0.01). No significant overall survival difference was observed among the stage II transverse colon tumors (P = 0.21). CONCLUSION: Surgical resection of locally advanced transverse colon tumors resulted in a higher morbidity and mortality than that of non-locally advanced tumors, but the benefit of extensive surgery in the case of locally advanced tumors cannot be underestimated. Furthermore, this benefit is more pronounced in the case of stage II tumors.

Outcomes of resection for colorectal cancer hepatic metastases stratified by evolving eras of treatment.

BACKGROUND AND PURPOSE: The outcomes and management of colorectal cancer (CRC) hepatic metastasis have undergone many evolutionary changes. In this study, we aimed to analyze the outcomes of patients with CRC hepatic metastasis in terms of the era of treatment. METHODS: We conducted a retrospective review of 279 patients who underwent liver resection (LR) for CRC hepatic metastases. The prognoses of patients treated pre-2003 (era 1) and post-2003 (era 2) were examined. RESULTS: Of the patients included in the study, 210 (75.3%) had CRC recurrence after LR. There was a significant difference in the ratio of CRC recurrence between the 2 eras (82.0% in era 1 vs. 69.5% in era 2; p = 0.008). Analysis of recurrence-free and overall survival rates also showed that the patient outcome was significantly better in the post-2003 era than in the pre-2003 era. Further analysis showed that a significantly higher percentage of patients in era 2 had received modern chemotherapeutic regimens including irinotecan and oxaliplatin, while patients in era 1 were mainly administered fluorouracil and leucovorin for adjuvant chemotherapy. Among patients with CRC recurrence, a significant ratio of those in era 2 underwent surgical resection for recurrent lesions, and these patients had a better survival curve than did patients without resection (34.1% vs. 2.2% for 5-year survival; p < 0.0001). CONCLUSION: The incidence of CRC recurrence after LR for hepatic metastasis remains very high. However, the management and outcomes of patients with CRC hepatic metastasis have greatly improved with time, suggesting that the current use of aggressive multimodality treatments including surgical resection combined with modern chemotherapeutic regimens effectively prolongs the life expectancy of these patients.

Preoperative carcinoembryonic antigen elevation in colorectal cancer.

UNLABELLED: BACKGROUND /AIMS: The aim of this study was to calculate the prevalence of elevated carcinoembryonic antigen (CEA) among colorectal cancer (CRC) patients and to evaluate the prognostic value of preoperative serum CEA levels in them. METHODOLOGY: Between 1995 and 2005, 8,861 consecutive patients were enrolled from a prospective database. CEA =5ng/mL was defined as elevated CEA. RESULTS: In the multivariate analysis, elevated preoperative CEA correlated with higher ages, circumferential tumors, colon tumors, large tumors, liver metastasis and high-stage (AJCC) tumors. After a 44-month median follow-up, elevated CEA was found to be an independent prognostic factor (odds ratio = 1.61) for overall survival in all 4 stages of the disease. The survival among patients with stage I tumors and elevated CEA (5-year survival rate = 74.7%) was not greater than that among patients with stage II tumors and no CEA elevation (5-year survival rate = 80.8%). CONCLUSIONS: Elevated preoperative CEA correlated with a higher age, circumferential tumors, colon tumors, large tumors, liver metastasis, and high-stage (AJCC) tumors. Elevated preoperative CEA indicates a potential poor prognosis even in early stage tumors. This poorer prognosis in the patients with stage I tumors and elevated preoperative CEA was not cancer specific.

Immunohistochemical study of vascular endothelial growth factor (VEGF) and matrilysin (MMP-7) in T1 adenocarcinoma of the colon and rectum to predict lymph node metastases or distant metastases.

BACKGROUND/AIMS: Predicting the lymph node metastatic or distant metastatic potential of T1 adenocarcinoma of the colon and rectum remains a major challenge. We investigated the role of the expressions of tumor matrilysin (MMP-7), VEGF-C and VEGF-A in predicting these metastatic potentials. METHODOLOGY: Single T1 adenocarcinomas were examined and pathological tumor factors were reviewed. Immunohistochemical staining of VEGF and MMP-7 was performed and the metastatic potential was defined on the basis of the presence of lymph nodes in the specimen or the identification of other distant metastasis during follow-up examinations. RESULTS: There was little correlation between the IHC staining results of VEGF-A, VEGF-C and MMP-7 in the same specimen (kappa<0.1). After a 61-month median follow-up (2-131 months), 17 (11.8%) tumors showed metastatic potential, including 14 lymph node metastases and 3 distant metastases. The tumors showing high levels of MMP-7 expression had higher metastatic potentials than those with low expression (19.1% vs. 8.2%, respectively; p=0.057). Overexpression of MMP-7 generally indicated an inferior overall survival (p=0.09). In analysis of the traditional pathological tumor factors, only lymphovascular invasion showed significance in predicting metastatic potential (p=0.04). CONCLUSIONS: Overexpression of MMP-7 generally indicated a higher metastatic potential and inferior overall survival. Lymphovascular invasion was a significant risk factor for lymph node metastasis.

Dickkopf-1 promotes hyperglycemia-induced accumulation of mesangial matrix and renal dysfunction.

Wnt/beta-catenin signaling mediates renal fibrosis in several model systems including diabetic nephropathy. Dickkopf-1 (DKK-1) is an endogenous inhibitor of Wnt/beta-catenin signaling, but whether DKK-1 modulates diabetic nephropathy is unknown. Here, we studied whether DKK-1 participates in high glucose (HG)-induced expression of profibrotic factors and renal damage. In vitro, HG increased expression of DKK1, receptor Kremen-2, TGF-beta1, and fibronectin in mesangial cells. Loss and gain of DKK1 function modulated HG-mediated c-Jun, TGF-beta1, and fibronectin expression. DKK1 mediated HG-induced phosphorylation of Ser45-beta-catenin and reduction of nuclear beta-catenin levels, but not phosphorylation of ERK kinase. Wnt3a protein and the beta-catenin (Delta45) mutation increased nuclear beta-catenin but abrogated HG-induced DKK1 and fibronectin expression. Exogenous DKK1 antisense oligonucleotide attenuated the increase in both serum DKK1 and urinary protein excretion in streptozotocin-induced diabetic rats. Knocking down DKK1 inhibited mesangial expression of TGF-beta1 and fibronectin and reduced both the glomerular volume and deposition of mesangial matrix in diabetic kidneys. Taken together, DKK1 mediates HG-induced destabilization of beta-catenin and matrix accumulation in mesangial cells. Knocking down DKK1 prevents diabetes-induced renal dysfunction and microstructure deterioration, suggesting that inhibition of DKK1offers therapeutic potential for diabetic nephropathy.

Carcinoma obstruction of the proximal colon cancer and long-term prognosis--obstruction is a predictor of worse outcome in TNM stage II tumor.

PURPOSE: Colon obstruction is suggested to be a predictor of poor outcome in colon cancer. However, the effect of obstruction on outcome in patients with different tumor-nodes-metastases (TNM) stage cancer has not been fully addressed. The aim of this study is to determine whether colon obstruction predicts surgical and long-term oncologic outcomes in patients with proximal colon cancer. METHODS: A total of 1,492 consecutive patients underwent open resection of primary adenocarcinoma of right colon in a single institution between January 1995 and December 2005. Clinical and follow-up data were extracted from a prospective colorectal cancer database. Univariate and multivariate analyses were performed to identify colon obstruction and other predictors of surgical and oncologic outcomes. RESULTS: Among 1,492 patients, 306 (20.5%) patients presented with colon obstruction. The rates of surgical morbidity and mortality were greater in patients with an obstruction as compared to patients without an obstruction (22.2% and 3.9% vs. 14.1% and 1.9%; p = 0.0005 and 0.041, respectively). Obstruction predicted a worse long-term disease-free survival (DFS) among patients with stage II-III disease (log-rank test, p = 0.0003). The data were stratified by TNM stage. Obstruction predicted a worse DFS among patients with TNM stage II cancer (598 patients; log-rank test, p = 0.001; Cox regression, p = 0.012), but it was not a predictor in TNM stage III cancer patients (424 patients; p = 0.116; p = 0.108). CONCLUSIONS: Colon obstruction was an independent predictor of long-term outcome only in TNM stage II but not in stage III proximal colon cancer. Patients with TNM stage II obstructive colon cancer could be included in future trials of adjuvant therapies.

Pathological examination of 12 regional lymph nodes and long-term survival in stages I-III colon cancer patients: an analysis of 2,056 consecutive patients in two branches of same institution.

PURPOSE: Pathologic examination of at least 12 lymph nodes (LNs) is widely accepted as a standard for colon cancer surgery. We sought to address its association with patient source, other clinicopathological factors, and survival by comparing information from two branches in a large single institution. METHODS: Patients with stages I-III adenocarcinoma of the colon between 1998 and 2003 were identified from the Chang Gung Colorectal Tumor Registry in two branches (Linkou and Kaohsiung branches) of same institution. We used multivariate analysis to adjust for variables with P < 0.1 in univariate analyses. RESULTS: A minimum of 12 examined nodes were observed in 80% of patients in Linkou branch versus 25% in Kaohsiung branch (P < 0.0001). Younger age, right hemicolectomy, larger tumor, higher tumor stage, higher caseload of surgeons, and patients at Linkou branch with an odds ratio (OR) as high as 23 (95% CI, 17-31) were independently associated with a higher frequency of ≥12 examined nodes. Patients with examined node number of <12 had a greater risk of recurrence within stages II and III (stage II: adjusted OR 1.88, 95% CI 1.27-2.79; stage III: adjusted OR 1.58, 95% CI 1.15-2.17) but not within stage I (OR 0.73, 95% CI 0.23-2.24). CONCLUSIONS: The results confirm that factors influencing nodal harvest are multifactorial and the examined LN number of 12 or more is associated with an increased long-term survival in stages II-III colon cancer. It is possible to adequately sample and examine a sufficient number of nodes in the majority of colon cancer specimens by standardized conventional methods.

Lead time of carcinoembryonic antigen elevation in the postoperative follow-up of colorectal cancer did not affect the survival rate after recurrence.

BACKGROUND AND AIMS: The role of carcinoembryonic antigen (CEA) in the early detection of recurrence during the postoperative follow-up of colorectal cancer remains unclear. We hypothesize that the tumor with longer lead time of CEA elevation to the definite recurrence may have a better prognosis because of its slower growth rate and closer observation. MATERIALS AND METHODS: From 1995 to 2003, 4,841 consecutive patients who received curative resection of localized colorectal adenocarcinoma were enrolled from a prospective database. The patients with persisting CEA elevation after operation had been already excluded. Postoperative follow-up, including physical examination, imaging, and CEA test, were performed according to a surveillance program. A CEA >/=5 ng/mL was defined as elevated. The definition of the CEA lead time was the period between CEA elevation and detection of recurrence. All statistical analyses were performed by SPSS package for Windows (Microsoft, Redmond, WA, USA). RESULTS: The postoperative median follow-up time for the 4,841 patients was 68 months. A total of 999 patients (20.6%) had CEA elevation and recurrence. Among these patients, recurrence was confirmed in 727 patients (72.8%)before, at the same time, or within 3 months of CEA elevation and thus had a short lead time of CEA elevation (SLT group). In 272 patients (27.2%), recurrence was confirmed after more than 3 months of CEA elevation and thus had a longer lead time of CEA elevation (LLT group). The recurrence pattern showed similarities in these two groups. A total of 193 patients (193/999, 19.3%) received a second radical operation, and 806 patients (80.7%) were inoperable. The re-resection rate between the SLT group (146 patients, 20.1%) and the LLT group (47 patients, 17.3%) was not significantly different. The overall survival rate after recurrence showed no difference between these two groups (P = 0.123). CONCLUSION: Most cases of recurrence were detected at nearly the same time when the CEA level was elevated. Therefore, a more sensitive test is needed for early detection. The relationship between the lead time of CEA and the clinical outcome was not statistically significant. A more aggressive approach to the patient who has CEA elevation and is highly suspect of recurrence may be needed.

Serum p53 antibody as tumor marker for follow-up of colorectal cancer after curative resection.

BACKGROUND: No large-scale studies have examined the use of serial measurements of serum p53 antibodies (s-p53Abs) combined with carcinoembryonic antigen (CEA) measurements during the follow-up of colorectal cancer (CRC) patients after curative resection. METHODS: A highly specific enzyme-linked immunosorbent assay was used to analyze s-p53Abs levels in 305 CRC patients before and after curative resection at a single institution. Agreement between recurrence and serial s-p53Ab and CEA measurements was evaluated by diagnostic accuracy odds ratio (DOR), kappa, and area under receiver operating characteristic curve (AUC). RESULTS: Among 305 patients, 76 (25%) patients had disease recurrence during follow-up. None of the 168 s-p53Ab seronegative patients (s-p53Ab < 10 U/microL) without recurrence had an abnormal s-p53Ab test during follow-up. Among the remaining low-level (10 U/microL 76 U/microL, n = 34) seropositive patients, recurrence defined by s-p53Ab tests resulted in a DOR of 4.3 and infinity, a kappa of 0.35 and 1.00, and an AUC of 0.633 [95% confidence interval (CI), 0.495 to 0.772; P = 0.047], and 1.0 (95% CI, 1.000 to 1.000; P < 0.0001), respectively. Recurrence defined by CEA tests had an AUC of 0.781 (95% CI, 0.654 to 0.909) for low-level and 0.796 (95% CI, 0.611 to 0.982) for high-level seropositive patients. CONCLUSIONS: Agreement between clinical recurrence and serial s-p53Ab test was dependent upon preoperative s-p53Ab level. Serial s-p53Ab testing outperformed CEA testing when predicting clinical recurrence in colorectal cancer patients with an abnormal preoperative s-p53Ab level.