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

• Published in: The American journal of surgery Vol. 223; no. 5; pp. 957 - 962
• Main Authors: Khan, Adil H., Gao, Xiang, Goffredo, Paolo, Kahl, Amanda R., Utria, Alan F., Charlton, Mary E., Ahad, Sajida, Hassan, Imran
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-05-2022; Elsevier Limited
• Subjects: Adenocarcinoma; Adenocarcinoma - diagnosis; Adenocarcinoma - epidemiology; Adenocarcinoma - therapy; Adenosquamous; Adenosquamous cancer; Adult; Cancer; Cancer therapies; Carcinoma, Adenosquamous - diagnosis; Carcinoma, Adenosquamous - epidemiology; Carcinoma, Adenosquamous - therapy; Carcinoma, Squamous Cell; Chemotherapy; Colon; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - diagnosis; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - therapy; Disease; Epidemiology; Histology; Humans; Medical prognosis; Metastases; Neoplasm Staging; Patients; Population; Prognosis; Radiation; Rectum; Squamous cell cancer; Squamous cell carcinoma; Standardization; Surgery; Surveillance; Survival; Trends; Tumors; United States > US; Adenocarcinoma; Adenosquamous cancer; Squamous cell cancer; Colorectal cancer
• ISSN: 0002-9610; 1879-1883
• DOI: 10.1016/j.amjsurg.2021.09.004

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).
Adult patients diagnosed with colorectal AC, SCC, and ASC between 2000 and 2017 were identified using Surveillance, Epidemiology, and End Results database.
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.
Colorectal ASC usually present with advanced stage and have overall worse prognosis. Standardization of treatment strategies may improve survival in colorectal ASC.
•Colorectal adenosquamous carcinoma is very rare among colorectal cancers with paucity of data regarding its natural history and prognosis.•Patients with ASC are more likely to present with more advanced stages and distant metastases compared to patients with Adenocarcinoma and Squamous cell carcinoma.•In the colon, major surgery was the mainstay of treatment for ASC, while in the rectum surgery chemotherapy and/or radiation were utilized in different combinations.•On multivariable analysis, Adenosquamous cancer was associated with poor prognosis compared to Adenocarcinoma.