Adenosquamous Carcinoma of the Colon and Rectum
Definition
- Carcinoma with malignant components exhibiting both glandular and squamous differentiation, arising in the colon and rectum
Covered separately
Diagnostic Criteria
- Must have a component of usual gland forming colorectal adenocarcinoma
- Must have a component of squamous carcinoma
- Must be more than occasional small foci
- Mixture may be intermingled or discrete foci
- Must not involve anal squamous mucosa
- Some require location >5-7 cm above dentate line
- Anal squamous carcinomas frequently extend into the rectum
- May be associated with inflammatory intestinal disorders
- Ulcerative colitis
- Schistosomiasis
- Amebiasis
- Prior radiation
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting : 1/31/10, 11/12/11
