A case report of ascending colon adenosquamous carcinoma with BRAF V600E mutation

Colorectal Adenosquamous Carcinoma: Demographics, Tumor Characteristics, and Survival Benefits of Surgery with Chemoradiation

BACKGROUND

Colorectal adenosquamous carcinoma (ASC) is a rare subtype of colorectal carcinoma. This study presents findings from a large database query to highlight the demographic, clinical, and pathological factors, prognosis, and survival of colorectal ASC.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients with colorectal ASC diagnosed between 2000 and 2020 and assess factors associated with overall survival (OS) and cause-specific survival (CSS).

RESULTS

Among 284 identified cases, the median age of diagnosis was 64 years. The majority of patients were White (69.0%), with income ≤ $70,000 ( 62.3%), and lived in metropolitan areas (85.6%). Regarding tumor characteristics, the majority of tumors were poorly differentiated (49.6%), regional stage (39.8%), size of > 4.0 cm ( 41.5%), and had a negative lymph node status (47.2%). Primary sites were the rectum (35.2%) and colon ( 64.8%). In patients with primary site to the rectum, the majority of treatment modality was multimodal therapy (40.0%). The main treatment modality for the primary site to the colon was surgery only (46.2%), followed by surgery + chemotherapy (34.2%). The overall 5-year survival was 31.3 (95% C.I. 28.4-34.2) and the 5-year cause-specific survival (CSS) was 40.1% (95% C.I. 36.9-43.3). Multivariate analysis showed age ≥ 60 years, regional stage, and distant stage were negative prognostic factors. An income of > $70,000, multimodal therapy, and surgery with chemotherapy were positive prognostic factors.

CONCLUSION

Colorectal adenosquamous carcinomas are more common in the non-Hispanic White populations and appear more frequently later in life (based on the median age of diagnosis at 64). Factors that contributed to a worse prognosis were an age of diagnosis ≥ 60 years, regional stage, and distant stage.

Presentation, treatment, and prognosis of colorectal adenosquamous carcinoma: A contemporary analysis of the surveillance, epidemiology, and end results database

INTRODUCTION

Colorectal adenosquamous carcinoma (ASC) represents <0.1% of colorectal cancers. Due to its rarity, there is paucity of data regarding its prognosis and treatment compared to other colorectal cancers. The aim of the study was to evaluate presentation, treatment and prognosis of colorectal ASC in comparison to adenocarcinoma (AC) and squamous cell carcinoma (SCC).

METHODS

Adult patients diagnosed with colorectal AC, SCC, and ASC between 2000 and 2017 were identified using Surveillance, Epidemiology, and End Results database.

RESULTS

Among the 446,132 patients diagnosed with colorectal cancer, 0.06% had ASC and were more likely to present with higher T stage and distant metastases compared to AC and SCC (p < 0.001). Major surgery was the primary treatment for colonic ASC, while for rectal ASC, chemotherapy and/or radiation were mainly utilized. Localized and distant colonic ASC had an unadjusted 5-year cause-specific survival that was worse than AC, while rectal ASC had the worst survival across all stages.

CONCLUSION

Colorectal ASC usually present with advanced stage and have overall worse prognosis. Standardization of treatment strategies may improve survival in colorectal ASC.

APC Mutations Are Not Confined to Hotspot Regions in Early-Onset Colorectal Cancer

Simple Summary

Mutation of the APC gene is a common early event in colorectal cancer, however lower rates have been reported in younger cohorts of colorectal cancer patients. In sporadic cancer, mutations are typically clustered around a mutation cluster region, a narrowly defined hotspot within the APC gene. In this study we used a sequencing strategy aimed at identifying mutations more widely throughout the APC gene in patients aged 50 years or under. We found high rates of APC mutation in our young cohort that were similar to rates seen in older patients but the mutations we found were spread throughout the gene in a pattern more similar to that seen in inherited rather than sporadic mutations. Our study has implications both for the sequencing of the APC gene in early-onset colorectal cancer and for the etiology of this disease.

Abstract

While overall colorectal cancer (CRC) cases have been declining worldwide there has been an increase in the incidence of the disease among patients under 50 years of age. Mutation of the APC gene is a common early event in CRC but is reported at lower rates in early-onset colorectal cancer (EOCRC) than in older patients. Here we investigate the APC mutation status of a cohort of EOCRC patients in New Zealand using a novel sequencing approach targeting regions of the gene encompassing the vast majority of known APC mutations. Using this strategy we find a higher rate (72%) of APC mutation than previously reported in EOCRC with mutations being spread throughout the gene rather than clustered in hotspots as seen with sporadic mutations in older patients. The rate of mutations falling within hotspots was similar to those previously seen in EOCRC and as such our study has implications for sequencing strategies for EOCRC patients. Overall there were low rates of both loss of heterozygosity and microsatellite instability whereas a relatively high rate (40%) of APC promoter methylation was found, possibly reflecting increasing exposure of young people to pro-oncogenic lifestyle factors.

Intestinal adenosquamous carcinoma with a synchronous skin metastasis: a immunohistochemical and molecular analysis

INTRODUCTION

Intestinal adenosquamous carcinoma (ASC) is a rare colorectal neoplasm frequently occurring at onset as a locally advanced disease with distant metastases. The liver is the most common site of metastasis, followed by the peritoneum and the lung. Cutaneous metastases from usual colorectal adenocarcinoma occur in about 3% of cases, both at the time of diagnosis in advanced disease and during the follow-up. To the best of our knowledge, skin metastasis from ASC has never been described, and no biological landscape of ASC has ever been investigated.

METHODS

We report a case of synchronous intestinal ASC and cutaneous single facial metastasis in a 70-year-old man with morphological, immunohistochemical, and molecular analysis of primary and metastatic lesions.

RESULTS

Primary and metastatic ASC showed the same morphological and immunohistochemical features. Target sequencing analysis revealed, both in primary tumor and metastasis, a pathogenic KRAS gene missense mutation c.38G > A p.(Gly13Asp) and a likely pathogenic CTNNB1 gene missense mutation c.94G > A p.(Asp32Asn). A nuclear localization of β-catenin protein in adenocarcinomatous component of primary and metastatic lesions was observed on immunohistochemistry.

CONCLUSION

We describe a case of single synchronous facial cutaneous metastasis from intestinal ASC showing KRAS and CTNN1B mutations both on primary and metastatic lesions.