Colon
Carcinoma
Squamous cell carcinoma
Author: Raul S. Gonzalez, M.D.
Last author update: 12 February 2021
Last staff update: 17 February 2021
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Squamous cell carcinoma[TI] colon[TI]
Table of Contents
Definition / general | Essential features | Sites | Etiology | Clinical features | Prognostic factors | Case reports | Treatment | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Sample pathology report | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Gonzalez RS. Squamous cell carcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/colontumorscc.html. Accessed December 17th, 2024.
Definition / general
- Rare primary malignancy of colorectum, representing 0.1% of cases (Am J Surg Pathol 1978;2:47)
Essential features
- Diagnosis requires finding no involvement of cloacogenic or squamous lined mucosa, no squamous cell carcinoma elsewhere and thorough sampling to exclude adenosquamous carcinoma (Surg Today 1994;24:75)
- Associated with ulcerative colitis, chronic colocutaneous fistula, schistosomiasis and colonic duplication (Dis Colon Rectum 1988;31:228, Cancer 1981;47:602)
- Aggressive clinical course with frequent metastasis (Saudi Med J 2006;27:874)
Sites
- Most common in proximal colon and rectum (Clin Colorectal Cancer 2001;1:55)
Etiology
- May arise from squamous metaplasia (Int J Surg Pathol 2009;17:340)
- Seemingly not related to HPV infection, except in rare cases (Eur J Surg Oncol 2002;28:657, Gastroenterology 2001;120:988)
Clinical features
- May cause hypercalcemia (Dig Surg 2005;22:371)
Prognostic factors
- Node negative cases have prognosis similar to colorectal adenocarcinoma (Dis Colon Rectum 2001;44:341)
Case reports
- 48 year old woman with squamous cell carcinoma arising in duplication of colon (Cancer 1981;47:602)
- 54 year old man with squamous cell carcinoma of colon with elevated serum SCC antigen (Clin Colorectal Cancer 2001;1:55)
- 59 year old woman with primary acantholytic squamous cell carcinoma of cecum (Diagn Pathol 2011;6:5)
- 60 year old woman with squamous cell carcinoma arising from longstanding colocutaneous fistula (World J Gastroenterol 2005;11:5251)
- Primary squamous cell carcinoma of colon arising in villous adenoma (Hum Pathol 1988;19:362)
Treatment
- Surgery, chemotherapy (Dis Colon Rectum 1999;42:102)
Gross images
Images hosted on other servers:
Rectal squamous cell carcinoma
Microscopic (histologic) description
- Similar to squamous cell carcinoma in other organs (polygonal eosinophilic cells with intercellular bridges and keratin formation)
- Can be poorly differentiated
- May be basaloid or acantholytic
Microscopic (histologic) images
Contributed by Raul S. Gonzalez, M.D.
Squamous cell carcinoma
Sample pathology report
- Ascending colon, resection:
- Squamous cell carcinoma of the colon (see synoptic report and comment)
- Comment: An immunohistochemical stain for p40 is diffusely positive.
Differential diagnosis
- Adenosquamous carcinoma:
- Carcinoma with squamous features but also malignant glandular component
- Angiosarcoma:
- Extension or metastasis from squamous cell carcinoma elsewhere (anus, lung, etc.) (Eur J Cardiothorac Surg 2001;19:719)
Board review style question #1
- Colonic squamous cell carcinoma can arise in the setting of
- Colonic epidermal inclusion cysts
- Diverticulitis
- HPV infection
- Schistosomiasis
Board review style answer #1
