Colloid carcinoma of the colon and rectum

Mucinous histology is a negative predictor of neoadjuvant chemoradiotherapy for locally advanced rectal adenocarcinoma

BACKGROUND

Neoadjuvant chemoradiotherapy (NCRT) followed by total mesorectal excision (TME) is the standard treatment for locally advanced rectal cancer (LARC). Mucinous adenocarcinoma (MAC) is a potential poor prognosis subgroup of rectal cancer. However, the predictive value of MAC in NCRT treatment of LARC is controversial.

METHODS

A comprehensive literature search of PubMed, Embase, and the Cochrane Library was performed. All studies examining the effect of MAC on CRT response in LARC were included. Outcomes of MAC were compared with non-specific adenocarcinoma (AC) by using random-effects methods. Data were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The main outcomes were the rates of pathological complete response (pCR), tumor and nodal down-staging, positive resection margin rate, local recurrence, and overall mortality.

RESULTS

Fifteen studies containing comparative data on outcomes in a total of 9,238 patients receiving NCRT for LARC were eligible for inclusion. MAC had a reduced rate of pCR (OR, 0.38; 95% CI, 0.18-0.78) and tumor down-staging (OR, 0.31; 95% CI, 0.22-0.44) following NCRT compared with AC. MAC did not significantly affect nodal down-staging (OR, 0.42; 95% CI, 0.16-1.12) after NCRT.

CONCLUSION

MAC of LARC was found to be a negative predictor of response to NCRT with lower rates of pCR and tumor down-staging for LARC. The nodal down-staging of MAC was relatively lower than that of AC, although the differences were not statistically significant.

Mucinous histology is associated with poor prognosis in locally advanced colorectal adenocarcinoma treated with postoperative first-line adjuvant chemotherapy: A systematic review and meta-analysis

PURPOSE

Postoperative adjuvant chemotherapy followed surgery is the standard management for localized advanced colorectal carcinoma (CRC). Mucinous adenocarcinoma (MAC) is a peculiar histological subtype of CRC, but the prognosis of MAC patients is controversial. The objective of this study is to assess the implication of MAC in survival of patients treated with surgery and firs-line adjuvant chemotherapy.

METHODS

Studies describing outcomes for advanced MAC and non-specific adenocarcinoma (AC) of CRC patients treated with first-line postoperative adjuvant chemotherapy followed surgery were searched in PubMed, Embase, Medline, EBSCO, Wiley, and Cochrane Library (January 1963-August 2021). Hazard ratios (HRs) of overall survival (OS), disease-free survival (DFS) and cancer-specific survival (CSS) for MAC to AC were extracted. Random-effects model was used for calculating the pooled HRs and 95% confidence interval (CI).

RESULTS

This meta-analysis is comprised of 8 studies involving a total of 124,303 CRC patients treated with first-line adjuvant chemotherapy followed surgery. The pooled HR for MAC was 1.23 (95% CI, 1.07-1.41, p < 0.01, I² = 80%), and the DFS (HR, 2.95, 95% CI, 1.22-7.14) of MAC patients were significantly poorer than AC patients. Similar results were also observed in stage III and FOLFOX regimen subgroups.

CONCLUSION

MAC was a risk factor for prognosis of localized advanced CRC patients treated with postoperative first-line adjuvant chemotherapy. Thus, the role of first-line adjuvant chemotherapy regimens should be further studied in these MAC patients.

Clinicopathological factors and survival outcomes of signet-ring cell and mucinous carcinoma versus adenocarcinoma of the colon and rectum: a systematic review and meta-analysis

BACKGROUND

Histological subtypes of colorectal cancer may be associated with varied prognostic features. This systematic review and meta-analysis aimed to compare clinicopathological characteristics, recurrence and overall survival between colorectal signet-ring cell (SC) and mucinous carcinoma (MC) to conventional adenocarcinoma (AC).

METHODS

A literature search of MEDLINE, EMBASE, Ovid and Cochrane Library was performed for studies that reported data on clinicopathological and survival outcomes on SC and/or MC versus AC from January 1985 to May 2020. Meta-analysis was performed using random-effect models and between-study heterogeneity was assessed.

RESULTS

Thirty studies of 1,087,055 patients were included: 11,510 (1.06%) with SC, 110,179 (10.13%) with MC and 965,366 (88.81%) with AC. Patients with SC were younger than patients with AC (WMD - 0.47; 95% CI - 0.84 to -0.10; I² 88.6%; p = 0.014) and more likely to have right-sided disease (OR 2.12; 95% CI 1.72-2.60; I² 82.9%; p < 0.001). Locoregional recurrence at 5 years was more frequent in patients with SC (OR 2.81; 95% CI 1.40-5.65; I² 0.0%; p = 0.004) and MC (OR 1.92; 95% CI 1.18-3.15; I² 74.0%; p = 0.009). 5-year overall survival was significantly reduced when comparing SC and MC to AC (HR 2.54; 95% CI 1.98-3.27; I² 99.1%; p < 0.001 and HR 1.38; 95% CI 1.19-1.61; I² 98.6%; p < 0.001, respectively).

CONCLUSION

SC and MC are associated with right-sided lesions, advanced stage at presentation, higher rates of recurrence and poorer overall survival. This has strong implications towards surgical and oncological management and surveillance of colorectal cancer.

Adenosquamous Carcinoma of the Colon. Case Report of an Unusual Type

Primary adenosquamous carcinoma of the colon is a rare entity. Its prevalent site of origin is at the level of the proximal portion of the large bowel. The tumor presents in young patients and follows a highly aggressive course. We present an extremely unusual case of adenosquamous carcinoma in which the classical mucinous and signet-ring cell adenocarcinoma was associated with the squamous component. The prognosis of this rare neoplasm is very poor.

Nuclear expression of claudin-3 in human colorectal adenocarcinoma cell lines and tissues

Claudins are members of a large family of transmembrane proteins, which are essential for the formation of tight junctions and have a significant effect on the biological behavior of tumor progression. Previous studies have demonstrated that several claudins show aberrant expression patterns in numerous types of cancer. The present study investigated the expression and localization of claudin-3 and claudin-7 in human colorectal adenocarcinoma cell lines and tissues. The protein expression levels of claudin-3 and claudin-7 were determined using immunocytochemical and immunohistochemical staining. Claudin-3, but not claudin-7, exhibited nuclear localization in the human colorectal adenocarcinoma Caco-2 and SW620 cell lines. Surgically resected colorectal adenocarcinoma tissue specimens were obtained, and the associations between the expression of claudin-3 or claudin-7 and various clinicopathological parameters were analyzed. The membranous expression rates of claudin-3 and claudin-7 were 58.0 and 50.0%, while their nuclear expression rates were 22.0 and 2.0%, respectively. The membranous expression of claudin-3 and claudin-7 was not associated with any clinicopathological factors, whereas the nuclear expression of claudin-3 was associated with histological type and was significantly increased in colorectal mucinous adenocarcinomas compared with that in well- to moderately-differentiated colorectal adenocarcinomas (P<0.01). However, no associations were observed between the nuclear expression of claudin-7 and any clinicopathological parameter. In conclusion, the nuclear expression of claudin-3 in colorectal mucinous adenocarcinoma may be involved in the biological transformation of tumors. The results from the present study indicated that claudin-3 is an important protein associated with histological type and has potential as a prognostic marker. Although the mechanisms underlying the nuclear localization of claudin-3 in tumorigenesis have not yet been elucidated in detail, the present results indicated the potential of claudin-3 as a histopathological biomarker for colorectal adenocarcinomas.

A critical reappraisal for the value of tumor size as a prognostic variable in rectal adenocarcinoma

Background and Objectives: To investigate critical prognostic factors for local recurrence in patients with rectal adenocarcinoma. Methods: We enrolled 221 consecutive patients who had histologically confirmed adenocarcinoma of the rectum and underwent surgery in our hospital between January 2000 and December 2014. Total mesorectal excision was performed in all patients undergoing a sphincter-sparing procedure or abdominal perineal resection of rectal cancer. To evaluate prognostic factors for local recurrence, we performed univariate and multivariate Cox regression analyses of the local recurrence rate in all patients. Overall survival rates were calculated using the Kaplan-Meier method, and Kaplan-Meier survival curves were compared using the log-rank test. Results: After the inclusion of only model variables of local recurrence with the highest or lowest univariate risk, a tumor size of <5 cm, a negative circumferential margin, well-to-moderately differentiated adenocarcinoma, low anterior resection, not receiving adjuvant RT, pathological T1-T3 stages, and upper- and middle-third rectal cancers were identified as strong prognostic factors with hazard ratios of 0.18, 0.20, 0.03, 0.01, 0.25, 0.18 and 0.18, respectively (95% confidence intervals [CIs], 0.06-0.58, 0.05-0.82, 0.03-0.38, 0.04-0.23, 0.05-0.64,0.09-0.70 and 0.06-0.54, respectively). After the multivariate Cox regression analysis of the local recurrence rate, a pathological tumor size of ≥5 cm was identified as the only prognostic risk factor (95% CI, 0.03-0.66; P = 0.013). The 5-year local recurrence rates among the patients having tumors measuring <5 cm and ≥5 cm in size were 1.40% and 23.00%, respectively (log-rank, P = 0.0001). The 5-year overall survival rates in the patients having tumors measuring <5 cm and ≥5 cm in size were 82.60% and 71.20%, respectively (log-rank, P = 0.001). Conclusion: A pathological tumor size of ≥5 cm is an independent prognostic factor for local recurrence in rectal adenocarcinoma.

Mucinous cholangiocarcinoma: Clinicopathological features of the rarest type of cholangiocarcinoma

Mucinous cholangiocarcinoma is extremely rare and its clinicopathological features remain unclear. The present study aimed to analyze published data on mucinous cholangiocarcinoma. Medical databases were searched from 1980 to 2016, and clinicopathological data for 16 mucinous cholangiocarcinoma patients were obtained. Characteristic imaging findings, including hypovascular tumor with peripheral enhancement on computed tomography and angiography, extremely high intensity on T2-weighted magnetic resonance images, intratumoral calcification and luminal communication between the tumor and bile duct on cholangiography, were noted. Mucinous cholangiocarcinoma was correctly diagnosed in one patient only, with some patients diagnosed as low-malignant biliary cystic tumors preoperatively. Five cases were followed up after the first medical examination, and three of these were initially diagnosed as biliary cystadenoma or intraductal papillary neoplasm of the bile duct. All five tumors showed marked enlargement within 4 months of follow up. Macroscopically, the resected tumors were non-cystic/solid in seven cases, and cystic in seven. Tumor diameter ranged from 5 cm to 22 cm, and mucoid cut surface, lobulation, lack of capsule and papillary growth were observed. Microscopically, co-existing intraductal papillary neoplasm of the bile duct was noted in three of five patients with available data. Nine of 10 cases in whom the pathological stage was reported had advanced disease with lymph node and/or distant metastasis, and 5-year survival was achieved in one microinvasive case only. Overall 1- and 3-year survival rates were 60.1% and 40.1%, respectively. The possibility of mucinous cholangiocarcinoma should be considered when biliary cystic tumors are detected on imaging modalities, despite the rarity of this tumor.

Pathologic Assessment of Rectal Carcinoma after Neoadjuvant Radio(chemo)therapy: Prognostic Implications

Neoadjuvant radio(chemo)therapy is increasingly used in rectal cancer and induces a number of morphologic changes that affect prognostication after curative surgery, thereby creating new challenges for surgical pathologists, particularly in evaluating morphologic changes and tumour response to preoperative treatment. Surgical pathologists play an important role in determining the many facets of rectal carcinoma patient care after neoadjuvant treatment. These range from proper handling of macroscopic specimens to accurate microscopic evaluation of pathological features associated with patients' prognosis. This review presents the well-established pathological prognostic indicators and discusses challenging features in order to provide both surgical pathologists and treating physicians with a checklist that is useful in a neoadjuvant setting.

Significance of the mucinous component in the histopathological classification of colon cancer

PURPOSE

Mucinous carcinoma is often independently classified as a histological type of colon cancer, but there are currently no established diagnostic criteria. The relationship between the proportions of mucinous components to the oncological outcomes was examined to determine whether mucinous carcinoma should be classified as an independent histological type.

METHODS

The study group comprised 1,038 patients with colon cancer. The relationships between the survival rates and recurrence patterns with the mucinous component area ratio (MC area ratio) and clinical variables were evaluated.

RESULTS

Tumors were classified into three groups: Group 1 (MC area ratio, 0 %), Group 2 (1-49 %), and Group 3 (≥50 %). Of the 1038 tumors studied, 877 (84 %) were classified as Group 1, 123 (12 %) as Group 2, and 38 (4 %) as Group 3. The tumor size was significantly larger in Group 3, and an increased MC area ratio was significantly related to a higher proportion of right-sided tumors. Among patients with stage II or III disease, stage III disease, poorly differentiated adenocarcinoma, and no adjuvant chemotherapy were poor prognostic factors. There was no relationship between the MC area ratio and the survival or recurrence pattern.

CONCLUSION

Mucinous carcinoma does not need to be classified as a separate histological type from ordinary differentiated adenocarcinoma.

Clinicopathological features, postoperative survival and prognostic variables for cancer-related survival in patients with mucinous colorectal carcinoma

PURPOSE

To investigate the clinicopathological features and postoperative survival of patients with mucinous colorectal carcinoma (MC) and to identify the factors related to long-term survival.

METHODS

Twenty-three patients who had undergone resection for MC at Miyazaki University Hospital from 1991 to 2006 were followed up for at least 5 years or until death. The effects of the clinicopathological variables on the 5-year cancer-specific survival were assessed by the univariate analyses. These patients' clinicopathological data were compared with those of 403 non-mucinous carcinoma (NMC) patients (102 well-differentiated adenocarcinomas, 301 moderately differentiated adenocarcinomas).

RESULTS

The 5-year cancer-specific survival rate was significantly worse in MC (56.2 %) than in NMC (73.8 %; p = 0.008) cases. Univariate analyses showed the T factor, lymph node metastases, liver metastases, metastases to the distant peritoneum, remote metastases and curative resection to be significant factors predicting the survival. However, there were no significant differences in the postoperative survival in patients with stage II-IV disease. The rates of metastases to the distant peritoneum, M1, T4, a tumor size ≥5 cm and non-curative resection were higher in MC than in NMC patients.

CONCLUSIONS

Patients with MC had advanced stage cancer, especially with metastases to the distant peritoneum, more frequently than did the patients with NMC. To improve the survival of these patients, it is therefore important to detect MC at an early stage and to perform curative resection.

Overall survival is improved in mucinous adenocarcinoma of the colon

INTRODUCTION

Debate persists regarding the relationship between mucin expression and outcome in colon cancer. This arises due to discrepancy in the definition of mucinous adenocarcinoma and the combination of both colon and rectal cancers in analyses. This study examines the relationship between increased mucin production and outcomes in colon cancer.

METHODS

Cases were classified according to the World Health Organization classification of mucinous adenocarcinoma of the colon. Accordingly, tumors were categorized as either (a) mucinous adenocarcinoma of the colon (greater than 50% of the extracellular matrix occupied by mucin) or (b) non-mucinous adenocarcinoma of the colon. Overall survival and disease-free survival were calculated. A stepwise Cox proportional hazards regression model was employed to determine the risk of death/disease recurrence. Kaplan-Meier estimates of overall survival and disease-free survival were plotted for each group and compared using a log-rank test.

RESULTS

On univariate analysis, mucinous adenocarcinoma was associated with reduced risk of death (P = 0.01). On multivariate analysis, mucinous adenocarcinoma was also associated with reduced risk of death (hazard ratio (HR) 0.33, 95% confidence interval (CI) 0.14-0.79, P = 0.01). Kaplan-Meier estimates confirmed improved rate of survival in the mucinous vs. non-mucinous group (P = 0.01). Mucinous adenocarcinoma did not affect disease-free survival (HR 0.75, 95% CI 0.46-1.21, P = 0.22). A comparison of Kaplan-Meier estimates for systemic recurrence demonstrated significant increases in systemic recurrence in the group with no mucin production (P = 0.04) but not for locoregional recurrence (P = 0.24).

CONCLUSIONS

Histopathological evidence of mucinous adenocarcinoma in colon cancer is associated with improved outcomes.

Magnetic resonance imaging defined mucinous rectal carcinoma is an independent imaging biomarker for poor prognosis and poor response to preoperative chemoradiotherapy

INTRODUCTION

Mucinous adenocarcinomas represent a potentially poor prognostic subgroup identifiable by imaging. We compared outcomes between magnetic resonance imaging (MRI) detected rectal mucinous carcinoma and adenocarcinomas. The diagnostic performance of MRI compared with initial biopsy in detecting mucinous adenocarcinoma was also assessed.

METHODS

The proportion of patients downstaged in the mrMucinous and adenocarcinoma groups was compared. Cox proportional hazard models were used to test independence of mucinous status and baseline MRI and clinical variables on survival. Differences in survival for mucinous versus non-mucinous tumours were tested for significance using the Mantel-Cox log rank test.

RESULTS

60/330 (18%) patients were correctly diagnosed with mucinous rectal cancer based on pre treatment MRI compared with 15/330 (5%) on initial biopsy (diagnostic odds ratio=4.67, p<0.05). All 60 (100%) patients undergoing surgery for mrMucinous tumours were confirmed as such on final histopathology. Significantly fewer mrMucinous tumours showed ypT downstaging when compared with non-mucinous tumours (14/60 (23%) versus 111/270 (40%), p=0.01). Three-year survival outcomes for patients for MRI detected mucinous tumours were significantly worse: disease free survival (DFS) was 48% versus 71%, p=0.006 and OS was 69% versus 79% p=0.04. MRI Mucin was an independent variable for poor DFS (hazard ratios (HR)) 0.58 95% Confidence interval (CI) 0.38-0.89).

CONCLUSIONS

MRI diagnosis of mucinous adenocarcinoma is diagnostically superior to preoperative biopsy and occurs in up to 20% of rectal cancer patients. It is an independent imaging biomarker for response to preoperative chemoradiotherapy (CRT) and prognosis. MRI documentation of mucinous status will enable future pursuit of treatment strategies in this poor prognostic subgroup.

Mucinous histology of colon cancer predicts poor outcomes with FOLFOX regimen in metastatic colon cancer

Mucinous adenocarcinoma (MA) of colorectal cancer seems associated with reduced responsiveness to chemotherapy. The overexpression of markers of resistance to fluorouracil and oxaliplatin has recently been demonstrated. We revised the outcomes of metastatic MA of the colon treated with FOLFOX. From January 2002 to December 2009, we treated 198 patients with metastatic colon cancer, of which 21 (10.6%) had diagnosis of MA and were compared with 42 control patients with non-mucinous adenocarcinoma (NMA). In MA group, three patients [14%; inhibitory concentration 95: ± 7.5%] reached partial response, and in NMA group, two patients obtained complete response and 16 obtained partial response with an overall response rate of 43% (inhibitory concentration 95: ± 7.6%) with a significant statistical difference (P = 0.027). Median progression-free survival for MA group was 4 months with respect to 8 months for NMA (P = 0.0001); regarding overall survival, we registered a median of 8 months with respect to 18 months for MA and NMA (P = 0.001). In multivariate analysis, MA histology, Eastern Cooperative Oncology Group performance status 2, more than two metastatic sites, and peritoneal metastatic involvement resulted in negative independent prognostic factors. Also in our study, MA is connected to poor prognosis and reduced activity of chemotherapy. In the absence of randomised studies, it may be convenient to analyse this subgroup of patients within the large trials carried out on colorectal cancer.

Mucinous differentiation in colorectal cancer--indicator of poor prognosis?

AIMS

  To analyse the prognostic impact of mucinous differentiation in colorectal mucinous adenocarcinomas and adenocarcinomas with a mucinous component.

METHODS AND RESULTS

  A total of 381 tumours were reviewed for mucinous differentiation by two independent pathologists. Mismatch repair status was assessed by immunohistochemistry. Prognostic significance was assessed by univariate and multivariate analyses. Eighty-one (21%) tumours were Union Internationale Contre le Cancer (UICC) Stage I, 120 (31%) Stage II, 126 (33%) Stage III and 54 (14%) Stage IV. Mucinous adenocarcinomas accounted for 12% and adenocarcinomas with a mucinous component for 19% of tumours. Mucinous differentiation was associated significantly with mismatch repair protein deficiency. The presence of extracellular mucin, regardless of extent, did not affect patients' outcome, while tumour grade, vascular and perineural invasion, tumour border configuration and budding were associated significantly with outcome. Cox analysis proved venous invasion to be an independent predictor of outcome in mucinous adenocarcinomas and both venous invasion and tumour budding as independent predictors of outcome in adenocarcinomas with any amount of mucin.

CONCLUSIONS

  Mucinous adenocarcinomas and/or adenocarcinomas with mucinous component do not differ from conventional adenocarcinomas with respect to prognosis and histological predictors of outcome. Hence, recording of mucinous differentiation may be used as an indicator of mismatch repair deficiency, but not for prognostic stratification.

Prognosis of mucinous histology for patients with radically resected stage II and III colon cancer

BACKGROUND

Previous studies investigating the prognostic role of mucinous histology of colorectal cancer produced conflicting results. This retrospective analysis was carried out in order to explore whether mucinous adenocarcinoma (MC) is associated with a comparatively worse prognosis than that of nonmucinous adenocarcinoma (NMC) for patients undergoing curative resection for stage II and III colon cancer.

PATIENTS AND METHODS

This study involved 1025 unselected patients who underwent curative surgery for sporadic colon cancer and follow-up procedures at six different oncology departments.

RESULTS

MCs accounted for 17.4% (n=178) of tumours. Patients with MC had 5- and 8-year overall survival rates of 78.6% and 68.8%, respectively, compared with 72.3% and 63.8%, respectively, for patients with nonmucinous tumours. Multivariate analysis using the Cox proportional hazards model showed that the clinically significant prognostic factors were stage of disease and adjuvant chemotherapy. No statistically significant interaction between mucinous histology and adjuvant chemotherapy was found.

CONCLUSIONS

For patients with stage II and III colon cancer who underwent curative surgery, mucinous histology has no significant correlation with prognosis compared with NMC. This retrospective analysis suggests a comparable benefit from adjuvant chemotherapy for MC compared with NMC.

Colon cancer in Iceland--a nationwide comparative study on various pathology parameters with respect to right and left tumor location and patients age

Increasing evidence suggests genetic, biological and demographical difference between right and left colon cancer. Studies have also indicated age differences in the pathology of colon cancer. There is a scarcity of large-scale studies that closely examine the pathological differences regarding age and tumor location. The aim of our study was to do an extensive comparison of right- and left- sided colon cancers as well as comparing patients <50 years with older patients. A retrospective, population-based study was carried out on all patients with colon cancer in Iceland between 1955 and 2004. A total of 2293 cases were analyzed (1148 men, 1145 women). All histopathology material was re-evaluated. Differences in tumor characteristics between right and left location and younger (<50) and older (≥50) patients was evaluated in particular. Higher TNM-stage, larger tumors, vessel invasion, mucinous type, high grade and expanding tumor border occurred more frequently in right- versus left-sided lesions while annular and polypoid tumors were more common in left-sided tumors (p < 0.05). Young patients had more frequent lymph node metastases, vessel invasion, nonpolypoid lesions and infiltrating tumor border (p < 0.05). Right-sided lesions show more aggressive features, reflected in morphology and stage. Younger patients present more frequently with adverse features than do older patients. Frequency of right- and left-sided colon cancer differs by age with pronounced age-location differences in females. This supports the assumption of differences in etiology and carcinogenesis of right- and left-sided colon cancer, and between young and old patients.

Primary mucin-producing tumours of the salivary glands: a clinicopathological and morphometric study

AIMS

To determine clinicopathological and morphometric features that discriminate between mucin-producing primary salivary gland carcinomas.

MATERIALS AND RESULTS

Fifteen mucin-producing tumours were stratified into five colloid carcinomas (CCs), four mucinous cystadenocarcinomas (MCAs), three mucin-rich salivary duct carcinomas (SDCs) and three mucin-rich mucoepidermoid carcinomas (MECs). The mean patient age was 70, 58, 43 and 63 years for CC, MCA, SDC and MEC, respectively. Eleven of 15 patients were female. The majority of CC cases originated from major salivary glands; MCA showed a predilection for the minor salivary glands. No disease-related mortality was observed in the CC group; one patient died in the MCA group, and one in the SDC group. Receiver-operating characteristic curve analysis revealed an optimal cut-off point of 17% of the tumour cells in contact with stroma that best distinguished between the CC and MCA. Histomorphometric measurements revealed that CC was best differentiated from MCA by smaller nuclear size and more regular chromatin.

CONCLUSIONS

Strict morphological criteria of CC coupled with assessment of the tumour cell/stroma relationship and the nuclear features facilitate discrimination between mucinous tumours of salivary gland.

Gene expression profiling of colorectal mucinous adenocarcinomas

PURPOSE

Although mucinous adenocarcinomas represent 6% to 19% of all colorectal adenocarcinomas, little is known about the genome-wide alterations associated with this malignancy. We have sought to characterize both the gene expression profiles of mucinous adenocarcinomas and their clinicopathologic features.

METHODS

Tumors from 171 patients with primary colorectal cancer were profiled using the Affymetrix HG-U133Plus 2.0 GeneChip with characterization of clinicopathologic data. Gene ontology software was used to identify altered biologic pathways.

RESULTS

Twenty (11.7%) mucinous adenocarcinomas and 151 (89.3%) nonmucinous adenocarcinomas were identified. Mucinous adenocarcinomas were more likely to be diagnosed with lymph node (LN) metastases (75% vs 51%, P = .04) and at a more advanced stage (85% vs 54%, P = .006) but long-term survival (5-y survival 58.9% vs 58.7%, P = NS) was similar. Mucinous adenocarcinomas displayed 182 upregulated and 135 downregulated genes. The most upregulated genes included those involved in cellular differentiation and mucin metabolism (eg, AQP3 + 4.6, MUC5AC +4.2, MUC2 + 2.8). Altered biologic pathways included those associated with mucin substrate metabolism (P = .002 and .02), amino acid metabolism (P = .02), and the mitogen-activated protein kinase cascade (P = .02).

DISCUSSION

Using gene expression profiling of mucinous adenocarcinomas, we have identified the differential upregulation of genes involved in differentiation and mucin metabolism, as well as specific biologic pathways. These findings suggest that mucinous adenocarcinomas represent a genetically distinct variant of colorectal adencarcinoma and have implications for the development of targeted therapies.

Mucinous histology predicts for poor response rate and overall survival of patients with colorectal cancer and treated with first-line oxaliplatin- and/or irinotecan-based chemotherapy

The objective of this study was to investigate the efficacy of first-line chemotherapy containing irinotecan and/or oxaliplatin in patients with advanced mucinous colorectal cancer. Prognostic factors associated with response rate and survival were identified using univariate and multivariate logistic and/or Cox proportional hazards analyses. The population included 255 patients, of whom 49 (19%) had mucinous and 206 (81%) had non-mucinous colorectal cancer. The overall response rates for mucinous and non-mucinous tumours were 18.4 (95% CI, 7.5–29.2%) and 49% (95% CI, 42.2–55.8%), respectively (P=0.0002). After a median follow-up of 45 months, median overall survival for the mucinous patients was 14.0 months compared with 23.4 months for the non-mucinous group (hazard ratio (HR), 1.74; CI 95%, 1.27–3.31; P=0.0034). After adjustment for significant features by multivariate Cox regression analysis, mucinous histology was associated with poor overall survival (HR, 1.593, 95% CI, 1.05–2.40; P=0.0267), together with performance status ECOG 2, number of metastatic sites ⩾2, and peritoneal metastases. This retrospective analysis shows that patients with mucinous colorectal cancer have poor responsiveness to oxaliplatin/irinotecan-based first-line combination chemotherapy and an unfavourable prognosis compared with non-mucinous colorectal cancer patients.

Correlação de fatores anatomopatológicos com a sobrevida de pacientes operados por adenocarcinoma colorretal

OBJETIVO: Avaliar a influência de fatores anatomopatológicos como prognóstico na sobrevida de pacientes operados de adenocarcinoma colorretal. MÉTODOS: Estudo tipo coorte histórica aberta, baseado na análise de 119 pacientes operados de adenocarcinoma colorretal com intenção curativa no Hospital Universitário Júlio Muller, no período de 1984 a 2002. Os dados foram obtidos dos prontuários médicos e de exames anatomopatológicos revisados, sendo submetidos à análise estatística de sobrevida em cinco anos pelo método de Kaplan & Méier. O reto foi o segmento mais acometido em 44,5% dos casos. O aspecto macroscópico tumoral predominante foi o ulcerado ou infiltrante (50,4%), com tamanhos entre 2 e 17 cm, sendo que a maioria dos tumores (64,7%) infiltrava até a camada serosa. O número médio de linfonodos analisados foi de 11,8(±7,3) por peça cirúrgica, indentificando-se nestes, 42,8% de metástases. A maioria dos tumores (85,4%) era bem ou moderadamente diferenciada. Foram observadas embolização angiolinfática e perineural em respectivamente 51,2% e 23,5%. RESULTADOS: Não houve significância estatística quanto a morfologia (p=0,87), tamanho do tumor (p=0,56) e grau de diferenciação celular (p=0,83). Os fatores que se correlacionaram com a sobrevida foram o sítio do tumor primário (p=0,04), a invasão angiolinfática intra-tumoral (p=0,02), invasão perineural (p<0,01), a infiltração das camadas (p=0,02), e o comprometimento linfonodal (p<0,01). CONCLUSÃO: A análise dos fatores anatomopatológicos mostrou correlação significativa da sobrevida com o sítio primário, a camada acometida, invasão perineural, invasão angiolinfática e comprometimento dos linfonodos.

Minimally invasive intraductal papillary-mucinous carcinoma of the pancreas: clinicopathologic study of 104 intraductal papillary-mucinous neoplasms

Invasive intraductal papillary-mucinous carcinoma (I-IPMC) is a heterogeneous entity with various postoperative outcomes. The aim of this study is to characterize early-stage I-IPMC with nonaggressive characteristics. One hundred and four patients with intraductal papillary-mucinous neoplasm (IPMN) were clinicopathologically investigated. The lesions were classified into 53 noninvasive IPMNs (adenoma, borderline, and noninvasive IPMC) and 51 I-IPMCs on the basis of the WHO classification. I-IPMCs were divided further into 26 minimally invasive IPMCs (MI-IPMCs) and 25 invasive carcinomas originating in IPMC (IC-IPMCs) by new diagnostic criteria proposed in this study. We examined invasiveness of I-IPMC on 4 patterns, and defined simple and practical diagnostic criteria of minimal invasion for each invasive pattern. The disease-specific survival rates after 3, 5, and 10 years were 100%, 100%, and 100% for both noninvasive IPMN and MI-IPMC, and 51%, 38%, and 0% for IC-IPMC. The overall and disease-specific survival rates for MI-IPMC were both significantly better than those for IC-IPMC (P<0.001), but there was no significant difference between noninvasive IPMN and MI-IPMC. Multivariate analysis showed that the factors indicative of poor prognosis were a diagnosis of I-IPMC classified as IC-IPMC and a high level of serum carbohydrate antigen 19-9. The prognosis of IC-IPMC was not significantly different from that of pancreatic ductal carcinoma in each of the corresponding tumor-node-metastasis stages. These findings suggest that a category of MI-IPMC provides more accurate and useful information of the stage and the aggressiveness of I-IPMC.

Two subtypes of mucinous adenocarcinoma of the colorectum: clinicopathological and genetic features

BACKGROUND

This work is aimed at comparing mucinous colorectal adenocarcinomas (MUC) and non-mucinous colorectal adenocarcinomas (non-MUC), and at verifying the existence of two different subgroups of MUC, in terms of clinicopathological features, chromosomal alterations, and outcome, in a geographical area where mucinous colorectal cancer resulted as being very frequent.

METHODS

One hundred and fifty-six unselected patients who underwent curative colorectal resection for sporadic colorectal cancer over a 4-year period were evaluated for histological classification as to MUC and non-MUC subtype, for microsatellite instability (MSI) using six microsatellite markers, and for the presence of p27, Fhit, and cyclooxygenase-2 (Cox-2). Molecular data, immunohistochemical results, recurrence frequency, and patient survival were analyzed statistically in relation to histological subtypes.

RESULTS

MUC accounted for 38.5% of all colorectal carcinomas. Compared to non-MUCs, MUCs were more frequently located in the proximal colon (p < 0.001), and more frequently showed MSI phenotype (p < 0.001), altered protein expression of hMlh1 (p = 0.030), Fhit (p <0.001), and p27 (p < 0.001). Compared to MUC with microsatellite-stable (MSS) phenotype, MUC with MSI more frequently resulted as being located in the proximal colon (p = 0.013), and more frequently showed altered expression of hMlh1 (p < 0.001), hMsh2 (p = 0.008), Fhit (p < 0.001), and p27 (p = 0.015). Significantly better survival of patients with proximal MUC (p = 0,012), with MSI MUC (p = 0.017), and with MUC with altered p27 expression (p = 0.02).

CONCLUSION

The results of the present study confirm that MUC represents distinct clinicopathological and genetic features as compared to non-mucinous tumors and support the hypothesis that MUC includes two subtypes with different genetic pathways and behavior.

Rapid reversal of interleukin-6-dependent epithelial invasion in a mouse model of microbially induced colon carcinoma

Chronic inflammation of mucosal surfaces renders them increasingly susceptible to epithelial cancers both in humans and mice. We have previously shown that anti-inflammatory CD4(+)CD45RB(lo)CD25(+) regulatory (Treg or T(R)) lymphocytes down-regulate inflammation and block development of bacteria-triggered colitis and colorectal cancer (CRC) in 129/SvEv Rag2-/- mice. Interestingly, T(R) cells collected from Interleukin (IL)-10-deficient cell donors not only failed to suppress carcinogenesis but instead promoted invasive mucinous colonic carcinoma with a strong gender bias expressing in male mice. We found we show that peritoneal invasion in this model is dependent on pleiotropic cytokine IL-6. Mucinous carcinoma arose rapidly and consistently after treatment with IL10-/- T(R) cells, which were found to express Foxp3+ and localize throughout tumor tissue. Carcinogenesis was rapidly reversible with transfer of wild type IL10-competent T(R) cells. Likewise, treatment with IL10-Ig fusion protein was sufficient to revert the lesions histologically, and restore inflammatory cytokine and oncogene expression to base line levels. These studies indicate an essential role for IL 6 in this CRC phenotype. Furthermore, immune-competent T(R) cells were important not only for preventing pathology but also for constructive remodeling of bowel following tumorigenic microbial insults. These data provide insights into etiopathogenesis of inflammation-associated epithelial invasion and maintenance of epithelial homeostasis.

Effects of radiotherapy on different histopathological types of rectal carcinoma

BACKGROUND

Down staging by pre-operative chemoradiotherapy is currently considered part of the standard therapeutic approach to rectal carcinoma. The aim of this study was to assess the response to chemoradiotherapy of different histopathological types of rectal carcinoma with emphasis on the mucinous variant.

METHOD

Between 1997 and 2002, 71 patients who received pre-operative chemoradiotherapy followed by surgery for rectal carcinoma were enrolled in the study. Staging of the rectal carcinoma was performed according to transrectal ultrasound findings (TN score) prior to the chemoradiotherapy. The chemoradiotherapy was followed by radical resection with mesorectal excision. All surgical specimens were examined by a single pathologist (MB). Pathological TN staging was assessed and tumour regression was graded according to a standard method (TRG1, complete response - TRG5 no response). Tumours were classified as mucinous or nonmucinous according to pre- and post-operative biopsy and specimen histopathological types. TN score change and TRG differences between groups were assessed.

RESULTS

Tumour regression was seen after chemoradiotherapy in 94.4% of the patients, while in 5.6% of the patients no response was found. The change in TN score and TRG were correlated. Higher TRG was associated with a smaller decrease in TN staging. TRG was significantly lower in the nonmucinous compared to the mucinous group and the decrease in TN grade was significantly larger in the nonmucinous group.

CONCLUSION

Mucinous carcinoma was associated with a lower response to pre-operative chemo-radiotherapy in this group of rectal carcinoma patients. Further studies are needed to determine its prognostic value.

Enhanced tumorocidal effect of chemotherapy with preoperative radiotherapy for rectal cancer: preliminary results--EORTC 22921

PURPOSE

The European Organisation for Research and Treatment of Cancer (EORTC) trial evaluated the addition of chemotherapy (CT) to preoperative radiation (preop RT) and the value of postoperative CT for improving the survival in patients with T3-4 resectable rectal cancer. Patients were allocated to the following four arms: arm 1, preop RT 45 Gy in 5 weeks; arm 2, preop RT plus two 5-day CT courses (fluorouracil 350 mg/m2/d and leucovorin 20 mg/m2/d) in the first and fifth week of RT; arm 3, preop RT plus four postoperative CT courses; and arm 4, preop RT and CT plus postoperative CT. We investigated the effect of adding CT on the pathologic parameters.

PATIENTS AND METHODS

One thousand eleven patients were entered onto the trial; 505 received preop RT (arms 1 and 3), and 506 received preop RT-CT (arms 2 and 4). We analyzed the differences in tumor size, tumor node stage, number of retrieved nodes, and histologic features such as lymphatic, venous, and perineural invasions, tumor differentiation, and tumor type.

RESULTS

After preop RT-CT, tumors were smaller (P < .0001), had less advanced pT (P < .001) and pN stages (P < .001), had small numbers of examined nodes (P = .046), and less frequent LVN invasions (P < or = .008). Mucinous tumors increased after preop RT-CT (P < .001).

CONCLUSION

In patients with rectal cancer, preliminary results of EORTC Trial 22921 indicate that the addition of CT to preop RT induces down-sizing, downstaging, and significant changes in histologic characteristics. Longer follow-up is needed to assess the impact on local control and survival.

Mucinous histology predicts for reduced fluorouracil responsiveness and survival in advanced colorectal cancer

BACKGROUND

Mucinous carcinoma of the colon and rectum (mucinous CRC) is a histological subtype of colorectal adenocarcinoma for which there is little data on chemotherapy responsiveness. The purpose of this study was to investigate specifically the efficacy of fluorouracil-based first-line chemotherapy in patients with advanced mucinous CRC.

PATIENTS AND METHODS

All patients with advanced mucinous CRC enrolled in three prospective randomized trials evaluating infused 5-fluorouracil as first-line treatment were compared with patients with non-mucinous subtypes enrolled in the same trials in a case-control study. Prognostic factors associated with overall response rate (ORR), progression-free survival (PFS) and overall survival (OS) were identified using univariate and multivariate logistic and/or Cox proportional hazards analyses.

RESULTS

The study included 135 patients (45 cases and 90 controls). The response rates for cases and controls were 22% [95% confidence interval (CI), 11% to 38%] and 47% (95% CI, 36.1% to 58.2%), respectively (P=0.0058). Median OS for the mucinous CRC patients was 11.8 months (95% CI, 8.87-14.8) compared with 17.9 months (95% CI, 13.38-22.39) in the control group (univariate analysis, P=0.056); after correcting for significant prognostic factors by multivariate Cox regression analysis, P=0.0372 and hazard ratio (HR)=1.497 (1.02-2.19).

CONCLUSION

Patients with advanced mucinous CRC have a poorer response to fluorouracil-based first-line chemotherapy and reduced survival compared with patients with non-mucinous CRC.

[Prognostic value of the grade of cellular differentiation, of mucus presence and the growth pattern of the invasive margin in colorectal adenocarcinomas Dukes B]

BACKGROUND

The unfavorable evolution of approximately 1/3 of the patients with colorectal cancer, classified in the Dukes B stage, shows to be desirable the addition of another approaches morphologic prognostics. The reports of the literature about prognostic significance of cellular differentiation, mucus presence and the pattern of growth of the invasive margin in colorectal cancer were controversial.

AIMS

To evaluate the prognostic significance of tumor differentiation, mucus presence and the growth pattern of the invasive margin in patients with colorectal carcinomas classified in Dukes B stage.

MATERIALS AND METHOD

A retrospective study of 156 patients who had undergone curative resection for colorectal cancer was made at the Department of Gastroenterology Surgery of the "Hospital do Servidor Público Estadual", in São Paulo, SP, Brazil. Their mean age was 58 (range 28-83) years and consisted of 94 (60.26%) women and 62 (39.74%) men. The cellular differentiation was classified in two degrees: low and high malignancy degree, in agreement with the area of predominant differentiation of the tumor. Tumors with at least 60% of its volume in mucus were called mucinous carcinoma. The growth of the invasive margin was classified as expanding when the tumor showed a well-delineated and circumscribed border pushing the adjacent structures and infiltrating when the tumor advances by a process of seemingly effortless dissection between the normal structures of the bowel wall.

RESULTS

There were predominance of tumors of low malignancy (139 (89.10%)), non-mucinous (142 (91.03%)) and with margin of the infiltrating type (123 (78.85%)). Only the growth of the invasive margin influenced the survival of 5 years. Patients with tumor exhibiting margin of the expanding type, presented a favorable outcome than those with margin of the infiltrating type -- 81.82% x 60.98%.

CONCLUSION

The type of growth of the invasive tumor margin may help to identify the prognosis of low and high-risk subgroups of patients.

Mucinous carcinoma of the colon: correlation of loss of mismatch repair enzymes with clinicopathologic features and survival

Colorectal carcinoma with microsatellite instability (MSI-H) has a characteristic clinicopathologic profile, typically forming right-sided, lymphocyte-rich tumors that are often mucinous. Mucinous histology in general has been linked to adverse prognosis in some studies, but not in others. MSI-H carcinoma, in contrast, has a better prognosis than microsatellite stable carcinoma in most studies. We assessed the relationship between MSI status, clinicopathologic features and outcome for 248 consecutive patients with resected mucinous carcinoma. All cases were reviewed to confirm mucinous histology. Immunohistochemical stains for DNA mismatch repair enzymes hMLH1, hMSH2 and hMSH6 were performed on a representative block from each case. Tumors lacking expression of a mismatch repair enzyme were designated MSI-H; all others were classified as microsatellite stable. Age, sex, tumor size, site, grade, stage, growth pattern, Crohn's-like reaction, vascular invasion and number of tumor-infiltrating lymphocytes were evaluated without knowledge of MSI status or patient outcome. 72 (29.3%) mucinous carcinomas were MSI-H. Compared to microsatellite stable mucinous cancers, they were more likely to be right-sided (83.3 vs 48.6%, P<0.001), have a Crohn's -like reaction (65.7 vs 29.8%, P<0.001) and have many tumor infiltrating lymphocytes (72.2 vs 20.8%, P<0.001). MSI-H mucinous cancers presented more often as localized disease (66.7 vs 38.1%, P<0.001) and less often with lymph node (26.4 vs 44.9%) or distant (4.2 vs 16.5%) metastases. In univariate analysis, MSI had a favorable effect on age-adjusted survival (hazard ratio 0.597, P=0.02). In multivariate analysis, age, grade, Crohn's-like reaction and stage were independent predictors of survival, but MSI status was not. In conclusion, MSI-H mucinous carcinomas are right-sided, low-stage tumors with Crohn's-like reaction and tumor-infiltrating lymphocytes. The outcome for MSI-H mucinous carcinoma is better than that of microsatellite-stable mucinous carcinoma, but MSI status is not an independent predictor of survival.

Pathologic prognostic factors in the recurrence of rectal cancer

For rectal cancer, local recurrence following surgical treatment is a grave complication that occurs in as many as 25% of cases. Pathological examination of the surgical resection specimen plays a primary role in assessing both the surgery- and tumor-related factors that contribute to the risk of recurrence. Among the tumor-related factors, stage has long been considered the single most accurate indicator of survival. However, recent evidence strongly suggests that the most powerful predictor of both local recurrence and overall outcome in the absence of distant metastatic disease is the macroscopic quality of the mesorectum in the resection specimen and the proximity of the tumor to the circumferential (radial) resection margin. Additional pathologic features have been shown to have stage-independent prognostic significance in colorectal cancer and may help to further define risk of adverse outcome. Such features include: tumor grade; histologic type; extent of extramural penetration by tumor; neural, venous, and/or lymphatic invasion; tumor border configuration; tumor budding; and host lymphoid response. The predictive value of tumor-specific molecular features is currently under investigation and may help to further improve prognostication and refine individual patient management in rectal cancer.

Colloid (mucinous noncystic) carcinoma of the pancreas

In the past, colloid (mucinous noncystic) carcinoma (CC) of the pancreas had been included under the category of ordinary ductal adenocarcinoma, a tumor with a dismal prognosis, or was frequently misdiagnosed as mucinous cystadenocarcinoma. The clinicopathologic features of CC have not yet been well characterized, because most cases on record have been parts of studies on either mucinous cystic neoplasms (MCN) or intraductal papillary mucinous neoplasms (IPMN), with which colloid carcinomas are frequently associated. To determine the clinicopathologic characteristics of CC, 17 pancreatic tumors composed predominantly (>80%) of CC (defined as nodular extracellular mucin lakes with scanty malignant epithelial cells) and in which the invasive carcinoma measured larger than 1 cm were studied. Ten of these were originally classified as mucinous ductal adenocarcinoma and four as mucinous cystadenocarcinoma. The mean age of the patients was 61 years; 9 were men and 8 were women. The mean size of the CC was 5.3 cm (range, 1.2-16 cm). In more than half of the patients, CC represented the invasive component of an IPMN (in nine cases) or MCN (in one case). The tumors were composed of well-defined pools of mucin with sparse malignant cells in various patterns of distribution. Signet-ring cells floating in the mucin (but not as individual cells infiltrating stroma, a characteristic finding of signet-ring cell adenocarcinomas) were commonly identified and were prominent in five cases. Perineurial invasion was noted in six cases and regional lymph node metastases in eight. Mutation in codon 12 of the k-ras gene was detected in only 4 of 12 cases studied and p53 mutation in 2 of 9. Immunohistochemical and histochemical mucin stains suggested luminalization of the basal aspects of the cells. Five-year survival was 57%. At an overall mean follow up of 57 months, 10 patients were alive with no evidence of disease (median, 79 mos), including four with lymph node metastasis, three others with perineurial invasion, and another with vascular invasion. Four patients died of disease (18, 18, 25, and 26 mos), and three died of thromboembolism (with persistent disease) at 2, 5, 10 months. All seven patients who died with or of tumor had undergone incisional biopsy of the tumor either before the operation or intraoperatively, whereas none of the patients who were alive had incisional biopsy. When compared with 82 cases of resectable ordinary ductal adenocarcinoma on whom follow-up and staging information was complete, it was found that the patients with CC present with larger tumors (p = 0.03) but lower stage (p = 0.01). The prognosis of CC is significantly better: 2-year and 5-year survival are 70% versus 28% and 57% versus 12%, respectively (p = 0.001). In conclusion, pancreatic CC may occur with or without an identifiable IPMN and MCN component, and should be distinguished from mucinous cystadenocarcinoma, ordinary ductal adenocarcinoma, and signet-ring cell adenocarcinoma. CC of the pancreas is associated with a significantly better prognosis than ordinary ductal adenocarcinoma. In addition to its distinctive morphologic and clinical characteristics, CC of the pancreas also appears to have a low incidence of mutation in codon 12 of the k-ras gene. In cases with a clinical suspicion of colloid carcinoma, the possibility that an incisional biopsy may contribute to thromboembolic complications or even dissemination of the tumor may need to be considered. The luminalization of the basal aspects of the tumor cells may be the cause of stromal mucin accumulation that characterizes colloid carcinoma and may act as a containing factor.

Clinicopathological characteristics of mucinous carcinoma of the colon and rectum

BACKGROUND AND OBJECTIVES

Clinicopathological significance of colorectal mucinous carcinoma (MC) remains controversial. The aim of the current study was to investigate the clinicopathological characteristics of colorectal MC.

METHODS

Eighteen patients with MC and 265 with moderately or well differentiated adenocarcinoma of the colon and rectum, were clinicopathologically compared.

RESULTS

MCs occurred in the right colon significantly more frequently than did non-mucinous carcinomas (NMCs). The maximal size of the tumors in MCs (7.0 +/- 2.9 cm) was significantly larger than that in NMCs (5.1 +/- 2.1 cm) (P < 0.001). Although the ratio of patients with peritoneal metastasis in MCs (22.2%; 4/18) was significantly higher than that in NMCs (6.0%; 16/265) (P < 0.05), there was no significant difference regarding liver metastasis. The proportion of lymph node metastasis in MCs (72.2%; 13/18) was significantly higher than that in NMCs (44.9%; 119/265) (P < 0.05). There was no significant difference regarding the lymphatic and venous invasion. The 1-, 3-, and 5-year survival rates of patients with MCs were 77. 8%, 45.4%, and 30.3%, respectively, and were significantly lower than those in patients with NMCs, that were 88.9 %, 65.6%, and 60.8%, respectively (P < 0.05).

CONCLUSIONS

As colorectal MCs proliferate and metastasize more rapidly than do NMCs, surgeons should realize that more aggressive surgical treatment should be occasionally administered to improve the postoperative prognosis of the patients with colorectal MCs.

American Joint Committee on Cancer Prognostic Factors Consensus Conference: Colorectal Working Group

BACKGROUND

The American Joint Committee on Cancer (AJCC), which regularly reviews TNM staging systems, established a working party to develop recommendations for colorectal carcinoma.

METHODS

A multidisciplinary consensus conference using published literature developed an arbitrary classification system of prognostic marker value (Category I, IIA, IIB, III, and IV), which forms the framework for this report.

RESULTS

The working party concluded that several T categories should be subdivided: pTis into intraepithelial carcinoma (pTie) and intramucosal carcinoma (pTim); pT1 into pT1a and pT1b corresponding to the absence or presence of blood or lymphatic vessel invasion, respectively; and pT4 into pT4a and pT4b according to the absence or presence of tumor involving the surface of the specimen, respectively. The working party also recommended that TNM groups be stratified based on the presence or absence of elevated serum levels of carcinoembryonic antigen (CEA) (>/= 5 ng/mL) on preoperative clinical examination. In addition, the working party also concluded that carcinoma of the appendix should be excluded from the colorectal carcinoma staging system because of fundamental differences in natural history.

CONCLUSIONS

The TNM categories and stage groupings for colorectal carcinoma published in the current AJCC manual have clinical and academic value. However, a few categories require subdivision to provide increasing discrimination for individual patients. The serum marker CEA should be added to the staging system, whereas multiple other factors should be recorded as part of good clinical practice. Although many molecular and oncogenic markers show promise to supplement or modify the current staging systems eventually, to the authors' knowledge none have yet been evaluated sufficiently to recommend their inclusion in the TNM system.

Prognostic significance of mucinous carcinoma of colon and rectum: a prospective case-control study

BACKGROUND AND OBJECTIVES

The clinical meaning of mucinous type of colonic and rectal carcinoma is still controversial. We used clinicopathological and follow-up data prospectively recorded for our series of colon and rectum cancer to compare 2 matched groups of mucinous and nonmucinous cancer patients.

METHODS

Two-hundred-forty-eight patients operated for colon and rectum cancer between January 1986 and January 1997 were considered. Thirty-six patients showed mucinous pattern on histologic examination but only 29 (11.7%) had more than 50% of mucin-secreting acini and could be classified as mucinous type. The 29 mucinous cancer patients were compared with 212 nonmucinous cancer patients to evaluate differences in epidemiological and clinical features. A control group from the nonmucinous patients was sorted by matching for age, sex, location, and Dukes stage.

RESULTS

In the case-control groups, survival was better for nonmucinous than for mucinous tumours. Many of the epidemiological findings already observed for mucinous carcinoma were also confirmed.

CONCLUSIONS

The existence of prognostic, clinical, and epidemiological differences between mucinous and nonmucinous colorectal carcinoma, together with the preliminary reports about their difference as to genetic features, could support the hypothesis that mucinous type is a distinct biological entity.

Distribution of newly formed vessels in human colorectal carcinomas with microangiography

OBJECTIVES

 Together, tumour cells and blood vessels compose a highly integrated ecosystem. This study was designed to investigate the distribution of newly formed vessels and the relationship of tissue structure to vascularity in human colorectal carcinomas.

SUBJECTS AND METHODS

 Microangiography, a silicone rubber compound injection method, was used successfully to study 18 resected colon cases. Vascular densities were evaluated by soft x-ray examination, and histological constitution was assessed by an ocular, square lattice, superimposing technique.

RESULTS

 On average, vascular density was 1.43 times greater (range 1.02-1.80) in tumour tissue than in normal mucosa. However, the vascular density in mucinous adenocarcinomas was significantly lower than that in well and moderately differentiated adenocarcinomas. When vascular densities were compared in an upper peripheral region (UR) and a lower central region (LR) (designated as upper and lower with reference to their position in relation to the submucosal vessels), the UR showed significantly higher vascular density than the LR. Histologically, the UR had a significantly higher density of carcinoma cells than the LR.

CONCLUSION

 These results suggest that the vascularity of colorectal carcinomas varies with respect to their topographical position and their histological subtypes.

Altered mucin expression is a field change that accompanies mucinous (colloid) breast carcinoma histogenesis

Mucinous carcinomas of the breast, so-called colloid carcinomas, exhibit better prognoses than their nonmucinous breast counterparts. This biological difference exhibited by mucinous breast carcinomas prompted us to examine the relationship of mucin expression to colloid carcinoma histogenesis. We studied 50 colloid carcinomas, 50 noncolloid cancers, and 50 normal breasts by hematoxylin-eosin (H&E) and Alcian blue staining, mucin immunohistochemistry, in situ hybridization with a battery of MUC riboprobes, and ancillary digital image analysis. We observed luminal mucin in normal ducts in 80% of colloid carcinomas compared with 10% of noncolloid carcinomas and 6% of normal breasts (P < .01). In the cases of colloid carcinoma that showed mucin-filled ducts, luminal mucin was observed in 40% of the normal ducts and acini, 40% to 75% of the ducts involved by hyperplasia, atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS), respectively, and in 50% of the co-incidental areas of cysts (mucoceles), adenosis, fibroadenoma, and intraductal papilloma (P < .01). Immunohistochemistry showed that colloid carcinomas showed strong MUC2 cytoplasmic immunoreactivity and decreased MUC1 immunoreactivity compared with noncolloid carcinomas. In situ hybridization studies indicated fivefold increased MUC2 signals and twofold increased MUC5 signals within adjacent and remote normal epithelium in only the colloid carcinoma cases (P < .01; P < .05). In these cases of colloid carcinoma, these increased MUC2 and MUC5 signals were also observed in areas of hyperplasia, ADH, DCIS, and invasive carcinoma. In contrast, the noncolloid carcinomas showed fivefold increased MUC1 signals but no increases in MUC2 or MUC5. In mixed colloid/noncolloid carcinomas, the colloid areas had identical mucin expression patterns as the pure colloid carcinomas, but there was a loss of MUC2 and MUC5 expression and a gain of MUC1 expression in the noncolloid areas that was therefore identical to the pattern observed in pure noncolloid carcinoma. In this study, we conclude that the altered expression of mucin so characteristic of colloid carcinoma is also a field change present in adjacent and remote normal breast epithelium.

A clinicopathologic study of mucinous gastric carcinoma including multivariate analysis

BACKGROUND

Mucinous gastric carcinoma (MGC) is a rare subtype of gastric adenocarcinoma, and its clinical and pathologic features are still controversial. To clarify the significance of this subtype of carcinoma, the authors conducted a case-control study to investigate the clinicopathologic characteristics of MGC and determine whether this mucin-producing histologic type is associated with a worse prognosis than other gastric carcinomas.

METHODS

Twenty-two cases of MGC and 46 patients with nonmucinous gastric carcinoma (NGC) were included. Patients were evaluated on the basis of age, gender, tumor size, location, depth of tumor invasion, histologic differentiation, lymph node involvement, organ metastasis, stage at presentation, surgical curability, adjuvant chemotherapy and radiation therapy. To determine whether the MGC itself was an independent prognostic factor, a multivariate analysis was performed with the Cox proportional hazards model.

RESULTS

The MGC patients were found to have larger tumors (P < 0.001), tumors more often located in the upper stomach (P < 0.05), more serosal invasion (P < 0.05), more lymph node involvement (P < 0.05), greater frequency of advanced stage disease (P < 0.01), and lower 5-year survival rates (P < 0.05) than NGC patients. There was no significant correlation between the subtypes of differentiation of MGC and other data, including the prognosis. Multivariate analysis showed that clinically important predictive factors were serosal invasion and disease stage at diagnosis. The mucinous histologic type itself was not an independent factor for poor prognosis.

CONCLUSIONS

The overall survival rate for patients with MGC was worse than that for patients with NGC. The poor prognosis was correlated with more advanced stage at diagnosis and more frequent serosal invasion, not with the mucinous histologic type.

Mucins secreted by cell lines derived from colorectal mucinous carcinoma and adenocarcinoma

Mucinous (colloid) carcinoma and well- to moderately-differentiated adenocarcinoma of the colon differ in the pattern and the amount of mucin secretion and perhaps in their behaviour and clinical outcome. To ascertain why these differences exist and to elucidate the mechanisms of tumour progression, we examined two model human cell lines derived from colorectal mucinous carcinoma (C1a) and moderately differentiated adenocarcinoma (HM3) which show typical pathological and mucin staining patterns of the respective type of carcinomas to nude mouse tumour xenografts. Specifically, we sought to determine if there were quantitative and qualitative differences in mucin synthesis, in mucin gene expression and in biological properties between the two model cell lines. Northern blot analysis showed that MUC2 mRNA levels were significantly higher in C1a cells compared with HM3 cells, while those of MUC3, -5 and -6 mRNA were lower. C1a cells secreted approximately five times more radiolabelled apomucin and 1.5 times more glycosylated apomucin than HM3 cells. When the carbohydrate side-chain length of secreted mucins by these cell lines were examined by beta-elimination followed by P4 column chromatography, C1a mucins had mostly short carbohydrate side-chains, while HM3 cells had predominantly longer side-chains. Western blot analysis of the cell homogenate showed higher expression of MUC2 apomucin and mucin-associated carbohydrate antigens, such as T, Tn and sialyl Tn, with decreased sialyl Le(x) expression in C1a cells compared with HM3. Immunohistochemical analysis of 35 colorectal adenocarcinoma and 25 mucinous colorectal carcinoma tissues also demonstrated increased MUC2 apomucin, T, Tn and sialyl Tn antigens in the mucinous cancer specimens. Examination of the biological properties of these cell lines showed that C1a cells had significantly higher in vitro invasive activity in assays of invasion and collagenase activity and significantly lower E-selectin binding and liver colonisation activities in nude mice. These results indicate that colorectal mucinous carcinoma cells differ considerably from colorectal adenocarcinoma cells, both qualitatively and quantitatively, in the pattern of mucin gene expression and in the synthesis and secretion of mucin. In addition, biological studies showed that mucinous carcinoma cells have a greater degree of invasiveness, but less liver colonising activity. These results suggest that the biological and mucin characteristics of mucinous carcinoma cells contribute to extensive local invasion through tissue stroma as the predominant mechanism of tumour progression, while the biological and mucin characteristics of well- to moderately-differentiated colorectal adenocarcinoma contribute to progression via distant metastasis formation.

Prognostic significance of radial margins of clearance in rectal cancer

A retrospective review of 325 patients was undertaken to analyse whether involvement of the radial resection margin (RRM) could predict locally recurrent disease or distant metastases in patients who had curative surgery for rectal or rectosigmoid cancer. Information on the RRM was available in 253 patients. The RRM was involved in 31 (12 per cent). Nine of these 31 patients developed local recurrence (29 per cent), while only 17 local recurrences were diagnosed in 217 patients (8 per cent) without involvement of the RRM (P < 0.01). At 2 years the overall local recurrence rate was 10 per cent. Distant metastases were diagnosed in 46 patients (18 per cent) and RRM involvement was identified as a prognostic factor depending on lymph node involvement (N stage) (P = 0.02). Local recurrence and some distant metastases result from microscopically incomplete resection. Assessment of the radial depth of tumour invasion by careful histological examination of x791p4ecimen may be used for selection of patients for adjuvant radiotherapy and/or chemotherapy.

Clinicopathological study of colorectal mucinous carcinoma in Taiwan: a multivariate analysis

The clinicopathological significance of colorectal mucinous carcinoma is controversial, although some authors feel mucinous carcinoma has a worse prognosis than that of non-mucinous carcinoma. To clarify the significance of this type of carcinoma in Taiwan, a retrospective review of patients with colorectal carcinoma treated at Chang Gung Memorial Hospital between 1984 and 1988 was undertaken. During this period, 53 mucinous carcinomas and 401 non-mucinous carcinomas fulfilling the inclusion criteria were analysed. Mucinous carcinomas were more common in patients 39 years of age or under (P < 0.005). Most mucinous carcinomas were located in the rectum/rectosigmoid, followed by the right colon; however, the right colon had a higher relative incidence (38 vs 8%, respectively; P < 0.005). Mucinous carcinomas presented at a significantly more advanced stage (23 vs 8%, respectively, stage D disease; P < 0.005) and had a markedly lower curative resection rate (68 vs 84%, respectively; P < 0.05). Following curative resection, mucinous carcinomas tended to have an increased incidence of subsequent distant metastasis (27.8 vs 18.8%, respectively; P < 0.005). The overall survival rate of patients with mucinous carcinoma was worse than that of non-mucinous carcinoma (P < 0.005). Multivariate analysis showed that clinically important predictive factors were stage of disease on diagnosis and subsequent distant metastasis. The mucinous histological type itself was not an independent prognostic factor in colorectal cancer.

Clinical research methodologies in diagnosis and staging of patients with peritoneal carcinomatosis

The following methodologies may be strictly applied to quantitatively evaluate patients with peritoneal carcinomatosis or sarcomatosis in regard to disease progression or regression: (1) Preoperative CT scan and the intraoperative assessment of cancer extent is analyzed region by region (AR-0-12) and an estimation of tumor volume (V0-V3) is evaluated according to the standardized scoring system previously described. At laparotomy, the volume of tumor nodules to adjacent organs, the viscosity (mucinous vs. solid) of tumor mass, and the pattern of distribution is assessed. (2) Radiologic abdominopelvic CT parameters that predict an incomplete cytoreduction are focal obstructions of bowel by CT assessment and tumor involvement of proximal ileum (AR-11). (3) The extent of prior surgical interventions (PS-1 through PS-3) must be recorded because aggressive deep dissections without perioperative chemotherapy severely jeopardize the possibility for complete cytoreduction. (4) Many tumor samples should be sent for histopathologic analysis. A proportion of mucin > 80% confirms a mucinous cancer. The malignant differentiation of cells, stroma morphology, the presence of signet ring cells, and evidence of invasion are used to grade cancers as mucinous tumor grade 0-3 (MTG-0 through MTG-3). (5) Once the cytoreductive procedure is accomplished, the surgeon estimates the residual volume of disease. (6) Objective response criteria from CT scan, tumor marker, and radiolabeled monoclonal antibody studies are necessary in a regular follow-up schedule.

Sucrase-isomaltase is an independent prognostic marker for colorectal carcinoma

PURPOSE

Expression of disaccharidase sucrase-isomaltase (SI) is significantly enhanced during neoplastic transformation of colonic epithelium. Our study was designed to determine whether expression of SI within primary tumors was significantly associated with survival in patients with colorectal carcinoma (CRC).

METHODS

SI expression was analyzed by immunohistochemistry in paraffin sections from 182 Stage I to III CRC that had been resected for cure at the New England Deaconess Hospital between 1965 and 1977. Expression was scored as absent or present in 1 to 50 percent or more than 50 percent of tumor cells. Associations were explored among SI expression, other clinical or pathologic variables, and overall survival. The data set is mature, with 91 (56 percent) patients who had died of CRC at a median follow-up of 96 months.

RESULTS

Fifty-five percent of primary CRC expressed SI. When the multivariate Cox analysis was performed, nodal status, T stage, primary site, grade, and SI expression were independent covariates. SI expression was not associated with the expression of other clinicopathologic variables but increased the risk of death from colorectal carcinoma by 1.83-fold.

DISCUSSION

These results indicate that SI is a prognostic marker for CRC that is independent of stage-related variables in patients who have undergone potentially curative resections.

Characterization of malignant colon tumors with 31P nuclear magnetic resonance phospholipid and phosphatic metabolite profiles

BACKGROUND

To further characterize selected pathologic features on a biochemical level, the authors analyzed the nuclear magnetic resonance metabolite and phospholipid spectra of 30 malignant colon tumors using 31P magnetic resonance spectroscopy.

METHODS

Eleven individual generic phospholipids were identified in the spectra of 17 phospholipid extracts, and 31 individual phosphatic metabolites were identified in the spectra of 13 perchloric acid extracts. The metabolites and lipids were quantified for statistical intergroup comparisons based on tumor stage, lymph node status, differentiation, mucin production, blood vessel invasion (BVI), and lymphatic vessel invasion (LVI).

RESULTS

Significant elevations in the relative concentration of alpha-glycerol phosphate were noted when comparing AJCC tumor classification (T3 vs. T2, 0.92 +/- 0.14 vs. 0.46 +/- 0.11, P < 0.009), tumor differentiation (moderately vs. well differentiated, 0.92 +/- 0.14 vs. 0.46 +/- 0.11, P < 0.009), and BVI (presence vs. absence, 1.03 +/- 0.04 vs. 0.68 +/- 0.10, P < 0.028) by elastic tissue stain. Among the tissue phospholipids analyzed, the relative concentration of a choline phospholipid was significantly different when comparing moderately and poorly differentiated tumors (6.26 +/- 0.56 vs. 3.29 +/- 0.30, P < 0.001), T2 and T3 tumors (3.90 +/- 0.45 vs. 6.31 +/- 0.56, P < 0.009), and mucin-positive vs. mucin-negative tumors (4.46 +/- 0.56 vs. 6.83 +/- 0.76, P < 0.028). Differences in lymph node status of the cases analyzed in this study (lymph node positive vs. lymph node negative) were noted for tumors with elevated levels of sphingomyelin (8.13 +/- 0.40 vs. 6.88 +/- 0.16, P < 0.02), diminished levels of phosphatidylinositol (5.25 +/- 0.27 vs. 6.38 +/- 0.34, P < 0.02), elevated levels of beta-glycerol phosphate (5.30 +/- 0.70 vs. 1.20 +/- 0.06, P < 0.05), and elevated levels of glycerol 3-phosphoserine (0.48 +/- 0.01 vs. 0.23 +/- 0.02, P < 0.002).

CONCLUSIONS

The characteristic differences in the phospholipid and intermediate phosphate metabolite profiles identified through magnetic resonance spectroscopic and histopathologic analysis may provide important information regarding the nature of tumor and cell membrane metabolism. Differences in these profiles may identify markers useful for biologic behavior, provide prognostic information, and characterize the impact of the pathologic features of colon cancer.

Primary signet-ring cell carcinoma of the colon and rectum

PURPOSE

Colorectal signet-ring cell carcinoma (SRCC) is uncommon; discordant data have been previously reported about clinicopathologic features. Thirty-four cases of primary colorectal SRCC were retrospectively reviewed to clarify controversies.

METHODS

Primary colorectal SRCC was diagnosed when the following criteria were satisfied: 1) the tumor was primary; 2) histologic material was adequate; 3) signet-ring cell represented more than 50 percent of the cancer.

RESULTS

We identified 34 cases (1.1 percent) of 2,995 consecutive large bowel cancers collected at the Institute of Anatomic Pathology of Florence between 1985 and 1993. Patients ranged in age from 31 to 89 (mean, 63.5; median, 65) years; 19 were male, and 15 were female (male:female = 1.3:1). Fifteen tumors were located in the proximal colon, 11 in the rectum, and 8 in the distal colon. The gross shape was infiltrative in 24 cases and exophytic in 10; only 6 cases (17.6 percent) showed features of linitis plastica. Most cancers (61.8 percent) were Stage C, 29.4 percent were Stage B, and distant metastases were present in only three cases (8.8 percent). No Stage A case was found. Prognosis was extremely poor, and overall five-year survival rate was 9.1 percent. Survival was influenced significantly by tumor stage (P < 0.01).

CONCLUSIONS

Comparison of our data with the literature showed many differences that could be related to different applied diagnostic criteria. We underlined the importance of histology as reproducible criterion for diagnosis of primary colorectal SRCC.

Pathological and immunohistochemical findings in a case of mucinous cholangiocarcinoma

A case of mucinous cholangiocarcinoma is reported. The patient was a 49 year old woman with the complaint of lumbago. Imaging examination disclosed a tumor 3.5 cm in diameter in the right hepatic lobe, which showed low density on computerized tomography scans and low signal intensity on T1-weighted magnetic resonance imaging (MRI) and high intensity on T2-weighted MRI. The hepatic tumor expanded rapidly and multiple pulmonary metastases and peritoneal dissemination developed. The patient died due to respiratory failure 5 months after the initial symptom. An autopsy, a massive tumor (9.5 cm in diameter) containing abundant mucus with several surrounding daughter nodules was found in the right hepatic lobe. Metastases were widespread. Histologically, the tumor was composed mainly of numerous lobulated mucus lakes in which adenocarcinoma cells floated. Admixed signet ring cells were also noted. These gross and histologic features differ from those in other mucin-producing hepatic tumors such as biliary papillomatosis and mucinous cystoadenocarcinoma. Immunohistochemically, the adenocarcinoma cells were strongly positive for carcinoembryonic antigen, Lewis Y, Tn, and T antigens and moderately positive for carbohydrate antigen 19-9, Lewis X, sialyl-Lewis X and sialyl-Tn antigen. Mature MUC1 mucin and core protein of MUC1 mucin were also expressed to varying degrees. The rapidly expanding, widespread metastases and poor prognosis found in the present case may be the clinicopathological features of mucinous cholangiocarcinoma.

Immunogenicity of synthetic TF-KLH (keyhole limpet hemocyanin) and sTn-KLH conjugates in colorectal carcinoma patients

Mucins of colorectal carcinomas overexpress the cancer-associated disaccharides Thomsen-Friedenreich antigen (TF) and sialyl-Tn antigen (sTn), making these antigens suitable for active specific immunotherapy. Patients at high risk for recurrent colon cancer, but free from disease after surgical resection, were immunized with synthetic TF and sTn covalently attached by a two-carbon crotyl linker to keyhole limpet hemocyanin (KLH). Four groups of patients were treated with TF-KLH without adjuvant, TF-KLH plus the immunological adjuvant Detox, sTn-KLH plus Detox, or sTn-KLH plus the immunological adjuvant QS-21, and the serological response was monitored. Enzyme-linked immunosorbent assay (ELISA), dot-blot immunostains, and inhibition assays were used to identify antibody responses against synthetic TF and sTn epitopes and against natural antigens, including asialoglycophorin expressing TF antigen, and ovine submaxillary mucin and the human colon cancer line LS-C expressing sTn antigen. Our results demonstrate that vaccines containing TF or sTn-KLH conjugates plus immunological adjuvants Detox and especially QS-21 induced high IgM and IgG antibody titers against the respective synthetic disaccharide epitopes. However, when tested against natural antigens expressing these disaccharide epitopes, IgM antibodies showed weak to moderate reactivity, while IgG antibodies were almost totally unreactive. On the basis of these results we are continuing to test modifications of synthetic TF and sTn epitopes to identify those that induce IgM and IgG antibodies that are more reactive with these antigens as they are expressed on tumor mucins.