Non-mucinous Adenocarcinoma Patients Research Articles

The impact of adjuvant chemotherapy on survival in mucinous and non-mucinous rectal adenocarcinoma patients after TME surgery.

The value of adjuvant chemotherapy for rectal cancer patients is debated and varies in different subgroups. One such subgroup is mucinous adenocarcinoma (MAC), which is more treatment resistant compared to non-mucinous adenocarcinoma (NMAC). To date, mucinous histology is not taken into account when deciding on adjuvant treatment strategy. This is the first study to exclusively include patients with rectal cancer, then separate MAC and NMAC and compare the survival in patients that had or did not have adjuvant chemotherapy. The study included retrospective register data from 365 Swedish patients with stage II-IV rectal adenocarcinoma, 56 patients with MAC and 309 patients with NMAC. All patients were considered curative, had surgery with total mesorectal excision in 2004-2013, and were followed up until death or 2021. Patients with MAC that had adjuvant chemotherapy had better overall survival (OS, HR 0.42; CI 95%: 0.19-0.93; p = 0.032) and a trend towards better cancer-specific survival (CSS, HR 0.41 CI 95%: 0.17-1.03; p = 0.057) compared to patients without chemotherapy (HR 0.42; CI 95%: 0.19-0.93; p = 0.032). The difference in OS was still significant even after adjusting for sex, age, stage, differentiation, neoadjuvant chemotherapy and preoperative radiotherapy (HR 0.40; CI 95%: 0.17-0.92; p = 0.031). There was no such difference in the NMAC patients except in the stage-by-stage subgroup analyses where patients in stage IV had better survival after adjuvant chemotherapy. There may be a difference in treatment response to adjuvant chemotherapy between MAC and NMAC patients. Patients with MAC could possibly benefit from adjuvant chemotherapy in stages II-IV. Further studies are however needed to confirm these results.

Post-operative chemotherapy improves the survival of patients with well differentiated widespread metastatic appendiceal non-mucinous adenocarcinomas.

Appendiceal adenocarcinoma is a very rare type of tumor, often asymptomatic in the early stages of development. Surgical resection is the most preferred intervention against appendiceal non-mucinous adenocarcinoma, but the efficacy of post-operative adjuvant chemotherapy is still unclear because the cancer is rare. Accordingly, we sought to characterize appendiceal non-mucinous adenocarcinoma profile that confers a better survival advantage for post-operative chemotherapy. We analyzed patients with appendiceal non-mucinous adenocarcinoma in the Surveillance, Epidemiology and End Results database, histologically diagnosed for the cancer between 2004 and 2015. Nearly half of the patients first underwent surgery and thereafter received post-operative chemotherapy. Logistic regression, Kaplan-Meier, univariate and multivariate Cox analysis were performed to evaluate the odds ratio for the propensity of patients underweening chemotherapy, whereas hazard ratios were used to evaluate the overall as well as cancer-specific survival. Of the 724 patients with appendiceal non-mucinous adenocarcinoma who underwent surgery, 301 (41.6%) received post-operative chemotherapy. Notably, patients with metastatic appendiceal non-mucinous adenocarcinoma were more likely to receive chemotherapy (OR =7.42, 95% CI: 5.34-10.39, P<0.001), similar to those with poor pathologically differentiated cancer types (OR =2.10, 95% CI: 1.49-3.00, P<0.001). However, univariate and multivariable Cox regression analyses found no significant overall survival and cancer-specific survival advantage for patients put on postoperative post-operative chemotherapy. In the disease stage and pathological differentiation groups, only patients with widespread metastatic (Stage IV) but well differentiated tumors displayed better 3-year (11.9% in overall survival, 11.5% in cancer-specific survival) and 5-year survival rate (7.8% in overall survival, 6.8% in cancer-specific survival) to post-operative chemotherapy. Staging and grading of appendiceal non-mucinous adenocarcinoma is invaluable in guiding the rationale of post-operative chemotherapy. Findings of this research support the view that only patients with both of widespread metastatic but well differentiated appendiceal non-mucinous adenocarcinoma should be considered for post-operative chemotherapy. Nonetheless, further prospective multidisciplinary clinical trials are necessary to further discern the use chemotherapy after surgery in appendiceal non-mucinous adenocarcinoma patients.

Clinicopathological and Molecular Features of Colorectal Cancer Patients With Mucinous and Non-Mucinous Adenocarcinoma.

BackgroundThe prognosis of mucinous adenocarcinoma (MAC) and non-mucinous adenocarcinoma (NMAC) in colorectal cancer (CRC) is controversial, and the molecular differences between them are unclear.MethodsBetween 2000 and 2010, a total of 1,483 CRC patients were included. Among them, 73 patients (4.9%) were diagnosed with MAC. The clinicopathological features and genetic alterations were compared between MAC and NMAC.ResultsAfter propensity score matching to balance age and sex between MAC and NMAC patients, 292 CRC patients (73 MAC and 219 NMAC) were enrolled in the analysis at a 1:3 ratio. In right-sided colon cancer, patients with MAC were more likely to have Borrmann types 3 and 4 tumors, poor differentiation, and advanced T category and tumor, node, metastasis (TNM) stage, chemotherapy, and a similar 5-year overall survival (OS) rate compared with patients with NMAC. In left-sided colon cancer and rectal cancer, patients with MAC were more likely to have Borrmann types 3 and 4 tumors, poor differentiation, lymphovascular invasion, advanced T and N categories and TNM stages, chemotherapy, and a worse 5-year OS rate than patients with NMAC. Regarding genetic alterations, for NMAC, right-sided colon cancer had more BRAF mutations than left-sided colon cancer and rectal cancer. For MAC, right-sided colon cancer was associated with more microsatellite instability-high tumors and more AKT1 mutations than left-sided colon cancer and rectal cancer.ConclusionThe genetic alterations are distinct between MAC and NMAC in CRC. Tumor location may have an impact on genetic alterations and patient prognosis in MAC and NMAC.

Clinicopathological characteristics and prognosis of colorectal mucinous adenocarcinoma and nonmucinous adenocarcinoma: a surveillance, epidemiology, and end results (SEER) population-based study

BackgroundMucinous adenocarcinoma (MC) is a rare histological subtype of colorectal adenocarcinoma. Previous studies investigating the prognosis of MC have conflicting results and the proper treatment of MC remains unclear.MethodsThis retrospective study presents the clinicopathological characteristics and prognosis of MC. This cohort study collected data from April 1 through August 01, 2018. This study used data on 107,735 patients with nonmucinous adenocarcinoma (NMC) and 9,494 with MC between 2009 and 2013 from the Surveillance, Epidemiology, and End Results program (SEER). Clinicopathological features were analyzed by chi-square test and survival curves by the Kaplan-Meier method. We used propensity score matching (PSM) to account for potential bias. Logistic regression and Cox proportional hazards models were used to compare and calculate adjusted risks of MC death.ResultsMC was more frequent in patients with older age, large tumor size and moderate tumor grade compared with NMC (P<0.001). Five-year survival was lower for MC patients than NMC patients (P<0.001). Older age, later tumor node metastasis (TNM) stage and multiple tumors indicated a poorer prognosis while surgery gave better survival outcomes [hazard ratio (HR) =0.38; 95% confidence interval (CI), 0.33 to 0.44; P<0.001]. Younger age, left-side colon location and early disease stage were associated with better survival after surgery (P<0.001).ConclusionsAge, TNM stage, tumor number and treatment were indicators of prognosis and surgery gave better survival for MC patients compared with those without surgery. Our study contributes to their clinical treatment.

Application of cAMP-dependent catalytic subunit β (PRKACB) Low Expression in Predicting Worse Overall Survival: A Potential Therapeutic Target for Colorectal Carcinoma.

Low expressions of PRKACB are related to the occurrence of various human malignancies. However, the prognostic value of PRKACB expression in colorectal cancer (CRC) patients remains controversial. In this analysis, PRKACB expression in CRC tumors was evaluated across the GEO, TCGA, and Oncomine databases, and a PRKACB survival analysis was performed based on the TCGA profile. We detected PRKACB in 7 GEO series (GSE110225, GSE32323, GSE44076, GSE9348, GSE41328, GSE21510, GSE68468) and TCGA spectra (all P <0.05). A meta-analysis performed in the Oncomine database revealed that PRKACB was significantly up-regulated in neoplastic tissues compared to normal tissues (all P <0.05). A Kaplan-Meier analysis demonstrated that lower PRKACB expression in tumors was significantly associated with poorer overall survival (OS) in patients with CRC (P <0.05). A subgroup analysis showed that low expression of PRKACB correlated with poor 1-, 3-, and 5-year OS (all P <0.05). Furthermore, in males (P = 0.0083), whites (P = 0.0463), and non-mucinous adenocarcinoma patients (P = 0.0108), the down-regulation of PRKACB expression was more significant for the OS prognostic value. Conclusion: PRKACB is down-regulated in tumors and associated with worsening OS in CRC patients.

The value of MR T2WI signal intensity related parameters for predicting pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Objective: To evaluate the value of T2WI signal intensity related parameters that can be obtained by magnetic resonance imaging (MRI) for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanved rectal cancer (LARC). Methods: Signal Intensity of Tumor (SIT) and Signal Intensity of Tumor/Muscle (SIT/M) of MR T2WI before and after neoadjuvant chemoradiotherapy of 101 patients with locally advanced rectal cancer were evaluated by two experienced readers independently. Signal Intensity of Tumor Reduction Rate (SITRR) and Signal Intensity of Tumor/Muscle Reduction Rate (SIT/MRR) were calculated. The difference of related parameters of T2WI tumor signal intensity between the pCR and the non-pCR group were analyzed. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance for predicting pCR. Results: Of the 101 patients, 18 were in pCR group and 83 were in non-pCR group. In all patients, the SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 1 were 197.0 (133.0), 144.2 (69.7), 0.4% (0.5%), 2.6 (0.6), 3.0 (2.3) and 0.4 (0.2)% in pCR group, and 227.0 (99.0), 205 (95.4), 0.1% (0.6%), 2.6 (0.6), 2.6 (1) in non-pCR group, respectively. SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 2 were 193.0 (135.0), 143.0 (69.8), 0.4% (0.2%), 2.6 (0.6), 1.5 (0.5) and 0.39% (0.2%) in pCR group, and 234.0(108.0), 203(96.5), 0.1% (0.3%), 2.6 (0.6%), 1.7 (0.7) and 0.25% (0.2%) in non-pCR group, respectively. Between the pCR and non-pCR group, there were significant differences in SITpost, SIT/Mpost and SIT/MRR measured by both readers (all P<0.01), but there was no significant differences in SITpre and SIT/Mpre (P>0.05). The difference of SITRR measured by reader 1 was not statistically significant (P=0.415), while the difference of SITRR measured by reader 2 was statistically significant (P=0.001). In patients with rectal non-mucinous adenocarcinoma, SITpost, SIT/Mpost, SITRR and SIT/MRR measured by two physicians were still statistically significant between the pCR and non-pCR group (all P<0.01), but SITpre and SIT/Mpre had no significant difference (P>0.05). ROC curve analysis showed that in all patients, the area under curve (AUC) of SITpost, SIT/Mpost and SIT/MRR for predicting pCR to neoadjuvant chemoradiotherapy in locally advanced rectal cancer was 0.694-0.762, the sensitivity was 68.2%-77.3%, and the specificity was 63.6%-77.3%. In rectal non-mucinous adenocarcinoma patients, the AUC, sensitivity and specificity was 0.704-0.764, 62.7%-78.9% and 66.2%-84.2%, respectively. Conclusions: T2WI signal intensity related parameters are potential predictors for pCR in locally advanced rectal cancer after neoadjuvant chemoradiptherapy. The predictive value is higher in non-mucinous adenocarcinoma.

Preoperative prediction for lymph node metastasis of rectal nonmucinous adenocarcinoma based on radiomics classifier

To determine the value of radiomics in identifying lymph node (LN) metastasis in patients with rectal nonmucinous adenocarcinoma. Methods: Imaging data of 91 patients were retrospectively analyzed (61 in the training set and 30 in the test set). A total of 1 301 radiomics features were extracted from high-resolution T2-weighted images of the whole primary tumor. The least absolute shrinkage and selection operator (LASSO) logistic regression was performed to choose the optimal features and construct a radiomics classifier in the training set. Its discrimination performance was compared with that of morphological criteria by receiver operating characteristic (ROC) curve analysis, which was validated in the test set. Results: The radiomics classifier combined with five key features was significantly associated with LN metastasis, which distinguished LN metastasis with an area under curve (AUC) at 0.874 (95% CI 0.787 to 0.960) in the training set, and the performance was similar in the test set (AUC 0.878, 95% CI 0.727 to 1.000). The AUCs according to the morphological criteria in the training set and test set were 0.619 (95% CI 0.487 to 0.752) and 0.556 (95% CI 0.355 to 0.756), respectively. Discrimination of the radiomics classifier was superior to that of morphological criteria in both the two datasets (both P <0.05). Conclusion: The radiomics classifier provides individualized risk estimation for LN metastasis in rectal nonmucinous adenocarcinoma patients and it has the advantage over the morphological criteria.

P-234 - Mucinous and non-mucinous adenocarcinoma in colorectal cancer patients

Introduction: The oncologic behavior of mucinous adenocarcinoma (MA) of colorectal differs from non-mucinous adenocarcinoma (NMA). MA is more advanced at diagnosis and has a poorer prognosis than NMA. We aimed to evaluate prognostic factors and survival rate in patients with MA compared with NMA in Western Iran. Methods: During 2008-2015 in a retrospective study, 83 patients with CRC referred to the Oncology Clinic in Kermanshah, Iran. Binary logistic regression analysis was used for the correlation between risk variables with the type of pathology. Results: The mean follow-up was 32 months (range, 12-72 months) and in this interval, there were 26 deaths and 3 patients were lost to follow-up and therefore, were omitted them from survival analysis. There was no significant correlation between NMA and MA with sex, degree of differentiation of tumor, tumor site, tumor size, KRAS mutation and lymph node metastasis, but a significant correlation was observed with age (P < 0.05). Binary logistic regression analysis showed there was a significant correlation between age (P = 0.01, odds ratio 11.93 and 95% CI 1.61-88.46) and type of pathology. The survival rate and mean survival were 54.3% and 23 months for NMA group, versus 80.6% and 25.4 months for MA group, respectively. Conclusion: The prevalence of NMA in CRC was more than MA. In this study, the MA patients had lower age and more risk of recurrence compared to NMA patients and unlike other studies, 5-year survival rate was significantly higher in NMA patients than that in MA patients.

Prognosis and value of preoperative radiotherapy in locally advanced rectal signet-ring cell carcinoma

As well known, signet-ring cell carcinoma (SRCC) is a rare histological subtype of colorectal adenocarcinoma, which has been associated with poor prognosis and resistant to non-surgery therapy compared with common adenocarcinoma. In this study, we assessed the effect of preoperative radiotherapy (PRT) for locally advanced rectal SRCC in a large patient group from the Surveillance, Epidemiology, and End Results program (SEER, 1988–2011) database. SRCC was found in 0.9% (n = 622) rectal cancer (RC) patients in our study. In the PRT setting, SRCC had significantly worse cancer-specific survival than mucinous adenocarcinoma and nonmucinous adenocarcinoma patients (log-rank, P < 0.001). In terms of SRCC, stage III RC patients benefited from PRT (log-rank, P < 0.001) while stage II did not (P = 0.095). The multivariate Cox proportional hazard model showed that PRT was an independent benefit factor in stage III rectal SRCC patients (HR, 0.611; 95% CI, 0.407–0.919; P = 0.018). In conclusion, SRCC was an independent predictor of poor prognosis in stage III RC patients, but not in stage II. In the PRT setting of locally advanced RC, SRCC patients had significantly worse prognosis. PRT was an independent prognostic factor associated with improved survival in stage III rectal SRCC.

Analysis of the clinicopathologic characteristics and prognostic of stage I invasive mucinous adenocarcinoma

The correlations between histological, clinical features and prognosis of stage I invasive mucinous adenocarcinoma (IMA) have not been thoroughly studied for its rare incidence. This study aimed to compare the prognosis among IMA with different percentage of mucinous component and the effect of adjuvant chemotherapy on IMA patients. A total of 145 stage I IMA and 3536 invasive nonmucinous adenocarcinoma patients with R0 resection were included. Based on the percentage of mucinous pattern presented in tumor, IMA were classified into two subgroups: pure mucinous (>90% invasive mucinous pattern) and mixed mucinous/nonmucinous (≥10% of each histologic component). Invasive nonmucinous adenocarcinomas were classified into three subgroups: lepidic (LEP), acinar/papillary (ACN/PAP) and solid/micropapillary (SOL/MIP). Disease-free survival (DFS) and overall survival (OS) were assessed and compared among IMA and invasive nonmucinous patients. For IMA patients, DFS (p=0.003) was worse for mixed mucinous/nonmucinous compared with pure mucinous subgroup, OS (p=0.514) was not prognostically different between two groups. There were no significant difference for DFS (p=0.428) and OS (p=0.232) between IMA and invasive nonmucinous adenocarcinoma. However, statistical significance were seen for DFS (p<0.001) and OS (p<0.001) between 5 major histological subgroups: LEP and pure IMA showed excellent prognosis, mixed mucinous/nonmucinous IMA and SOL/MIP subtypes presented the worst prognosis. No significant survival benefit from adjuvant chemotherapy for IMA patients. Mixed mucinous/nonmucinous IMA had a worse DFS compared with pure mucinous. Early stage IMA could not benefit from adjuvant chemotherapy.

Prognostic Significance and Molecular Features of Colorectal Mucinous Adenocarcinomas

Mucinous adenocarcinoma (MC) is a special histology subtype of colorectal adenocarcinoma. The survival of MC is controversial and the prognostic biomarkers of MC remain unclear. To analyze prognostic significance and molecular features of colorectal MC. This study included 755,682 and 1001 colorectal cancer (CRC) patients from Surveillance, Epidemiology, and End Results program (SEER, 1973-2011), and Linköping Cancer (LC, 1972-2009) databases. We investigated independently the clinicopathological characteristics, survival, and variety of molecular features from these 2 databases. MC was found in 9.3% and 9.8% patients in SEER and LC, respectively. MC was more frequently localized in the right colon compared with nonmucinous adenocarcinoma (NMC) in both SEER (57.7% vs 37.2%, P < 0.001) and LC (46.9% vs 27.7%, P < 0.001). Colorectal MC patients had significantly worse cancer-specific survival (CSS) than NMC patients (SEER, P < 0.001; LC, P = 0.026), prominently in stage III (SEER, P < 0.001; LC, P = 0.023). The multivariate survival analysis showed that MC was independently related to poor prognosis in rectal cancer patients (SEER, hazard ratios [HR], 1.076; 95% confidence intervals [CI], 1.057-1.096; P < 0.001). In LC, the integrated analysis of genetic and epigenetic features showed that that strong expression of PINCH (HR, 3.954; 95% CI, 1.493-10.47; P = 0.013) and weak expression of RAD50 (HR 0.348, 95% CI, 0.106-1.192; P = 0.026) were significantly associated with poor CSS of colorectal MC patients. In conclusion, the colorectal MC patients had significantly worse CSS than NMC patients, prominently in stage III. MC was an independent prognostic factor associated with worse survival in rectal cancer patients. The PINCH and RAD50 were prognostic biomarkers for colorectal MC patients.

Relation of glypican-3 and E-cadherin expressions to clinicopathological features and prognosis of mucinous and non-mucinous colorectal adenocarcinoma.

Glypican-3 (GPC3) is a member of the membrane-bound heparin sulfate proteoglycans. E-cadherin is an adhesive receptor that is believed to act as a tumor suppressor gene. Many studies had investigated E-cadherin expressions in colorectal carcinoma (CRC) while only one study had investigated GPC3 expression in CRC. This study aims to investigate expression of GCP3 and E-cadherin in colorectal mucinous carcinoma (MA) and non-mucinous adenocarcinoma (NMA) using manual tissue microarray technique. Tumor tissue specimens are collected from 75 cases of MC and 75 cases of NMA who underwent radical surgery from Jan 2007 to Jan 2012 at the Gastroenterology Centre, Mansoura University, Egypt. Their clinicopathological parameters and survival data were revised and analyzed using established statistical methodologies. High-density manual tissue microarrays were constructed using modified mechanical pencil tip technique and immunohistochemistry for GPC3 and E-cadherin was done. NMA showed higher expression of GPC3 than MA with no statistically significant relation. NMA showed a significantly higher E-cadherin expression than MA. GPC3 and E-cadherin positivity rates were significantly interrelated in NMA, but not in MA, group. In NMA group, there was no significant relation between either GPC3 or E-cadherin expression and the clinicopathological features. In a univariate analysis, neither GPC3 nor E-cadherin expression showed a significant impact on disease-free survival (DFS) or overall survival (OS). GPC3 and E-cadherin expressions are not independent prognostic factors in CRC. However, expressions of both are significantly interrelated in NMA patients, suggesting an excellent interplay between both, in contrast to MA. Further molecular studies are needed to further explore the relationship between GCP3 and E-cadherin in colorectal carcinogenesis.

Prognosis and value of adjuvant chemotherapy in stage III mucinous colorectal carcinoma

BackgroundColorectal mucinous adenocarcinoma (MC) has been associated with impaired prognosis compared with nonmucinous adenocarcinoma (NMC). Response to palliative chemotherapy is poor in metastatic disease, but the benefit of adjuvant chemotherapeutic treatment has never been assessed in large patient groups. This study analyses overall survival and efficacy of adjuvant chemotherapy in terms of survival in patients following radical resection for MC. Patients and methodsThis population-based study involved 27 251 unselected patients diagnosed with colorectal carcinoma between 1990 and 2010 and recorded in a prospective pathology-based registry. Kaplan–Meier analysis and log-rank testing were used to estimate survival. Cox proportional hazard model was used to calculate multivariate hazard ratios for death. ResultsMC was found in 12.3% (N = 3052) of colorectal tumors with a different distribution compared with NMC, with 24.4% located in the rectum and 54.3% in the proximal colon (versus 38.0% and 30.6%), P < 0.0001. NMC was more often classified as stage I disease than MC (20.5% versus 10.9%), P < 0.0001. After adjustments for covariates, MC was associated with a higher risk of death only when located in the rectum [hazard ratio 1.22; 95% confidence interval (CI) 1.11–1.34]. Multivariate regression analysis showed a similar survival after adjuvant chemotherapy for stage III MC and NMC patients. ConclusionsThe poor prognosis for MC is only present in rectal cancer. In the adjuvant setting, there is no difference in the efficacy of chemotherapy between MC and NMC; therefore, current adjuvant treatment recommendations should not take histology into account.

TNM Stages and Prognostic Features of Colorectal and Mucinous Adenocarcinoma Patients: a Meta Analysis

The significance of the mucinous adenocarcinoma in TNM staging and prognosis for colorectal tumor patients is still controversial. The aim was to provide a meta-analysis for TNM staging and prognostic features of colorectal tumors. 30 individual case-control studies were finally included into this meta-analysis, involving a total of 444,489 cancer cases and 45,050 mucinous adenocarcinomas, of relations with TNM staging and prognostic features. Compared to non-mucinous adenocarcinoma patients, the TNM IV stage accounted for a larger percentage of mucinous adenocarcinomas (OR=1.48, 95%CI 1.28-1.71, POR<0.001) and the prognosis was significantly poor (HR=1.06, 95%CI 1.04-1.08, P<0.001). After heterogeneity testing, the results was similar to the holistic approach outcome (HR=1.48, 95%CI 1.35-1.62, P<0.001). Compared to patients with non-mucinous adenocarcinomas, mucinous adenocarcinoma patients with later TNM staging make up a big percentage, and mucinous adenocarcinoma is an independent risk factor for poor prognosis.

Clinical features of colorectal mucinous adenocarcinoma

To investigate the clinicopathological characteristics and prognosis of colorectal mucinous adenocarcinoma (MAC) and non-mucinous adenocarcinoma (NMAC). Clinical data of 2089 cases with colorectal cancer from 1994 to 2007 in our hospital, including 169 patients diagnosed as mucinous adenocarcinoma were analyzed retrospectively. As compared to NMAC, the tumor diameter of MAC was longer[(5.52+/-3.56) cm vs (4.62+/-2.68) cm, P<0.01]; the age of MAC was younger [(52.3+/-16.5) vs (58.7+/-13.6) years, P<0.01]. The rates of tumor location in colon (97 cases,57.4% vs 814 cases, 44.3%, in MAC and NMAC) were significantly different (P<0.01). Compared with NMAC, MAC had more lymph node involvement (103 cases, 60.9% vs 929 cases, 50.1%), more often in serosa infiltration (116 cases, 68.7% vs 914 cases, 49.8%), more peritoneal dissemination (26 cases, 15.4% vs 125 cases, 6.8%), and adjacent organ invasion (44 cases, 26.0% vs 300 cases, 16.3%) (P<0.01). The rate of radical resection (86.4% vs 91.5%), hepatic metastasis (5.3% vs 8.5%) and local recurrence had no significant difference between patients with mucinous and non-mucinous adenocarcinoma (P>0.05). In comparison to NMAC patients, MAC patients were worse in long-term overall survival, the survival of receiving radical resection and of TNM stage (II+III) group (P<0.01). Survivals were not significantly different in TNM stage I and IV groups between mucinous and non-mucinous adenocarcinoma (P>0.05). Colorectal mucinous adenocarcinoma patients have worse outcome in comparison to non-mucinous adenocarcinoma patients. Mucinous adenocarcinoma may have special biological behavior, which is an independent prognostic factor for patients with colorectal cancer.

Survival of patients diagnosed with either colorectal mucinous or non-mucinous adenocarcinoma: A population-based study in Canada

Previous studies have shown conflicting results on the prognosis of colorectal mucinous adenocarcinoma. This study compared prognostic characteristics of patients diagnosed with mucinous and non-mucinous adenocarcinomas in a Canadian series. Analyses were based on 165 colorectal mucinous and 1215 non-mucinous adenocarcinoma patients who were registered at the Ottawa Regional Cancer Centre from 1994 to 1997, with follow-up extending to December 31, 2001. Differences in survival were examined using the relative survival analysis and the Cox proportional hazards model. For colon, rectum and both combined, the distribution for age at diagnosis, stage and treatment of patients with mucinous adenocarcinoma was similar to that of non-mucinous patients (all p > or = 0.12). Patients with mucinous histology had fewer well- or moderately-differentiated tumours than non-mucinous patients (all p < 0.01). Overall, no statistically significant differences were noted in 5-year relative survival between mucinous and non-mucinous carcinoma for colon, rectum and their combination (p > or = 0.35 for each). However, when the stages were considered separately, patients with stage III mucinous carcinoma had worse survival than patients with non-mucinous carcinoma for both sites. Multivariate analysis of combined data for colon and rectal cancers indicated that independent significant prognostic factors were stage for mucinous, with age and grade as well as stage for non-mucinous carcinoma. In conclusion, no significant differences in stage distribution and overall survival were found between mucinous and non-mucinous patients for colorectal cancer.