title: Case report of primary squamous carcinoma of the rectum.
abstract: OBJECTIVE
  To report a patient with primary squamous carcinoma of the rectum.
  
  
  METHODS
  A 40-year-old woman with hematochezia and change in bowel habits was studied. The main laboratory finding was a mild anemia. A barium enema and a proctoscopy revealed a rectal neoplasm at eight cm from the anal verge. A transendoscopic biopsy demonstrated an squamous rectal carcinoma. A transrectal ultrasound and CT scan of the abdomen revealed a big rectal mass with transmural affection and possible involvement of the lymph nodes. The carcinoembriogenic antigen (CEA) was high (32 ng/mL). The patient underwent radiotherapy with 46 Gy, and 5-fluorouracil as radiosensitizer. Three months later, a new CT scan showed significant reduction of the size of the mass, and the patient underwent a very low anterior resection with double-stapled anastomosis. The analysis of the specimen showed a squamous carcinoma of the mid-rectum, invading through the wall without lymph node affection and with proximal, distal, and radial margins free of tumor. The CEA returned to normal after surgery (1.3 ng/mL). The patients is alive and without evidence of disease 18 months after the operation.
  
  
  CONCLUSIONS
  Primary squamous carcinoma of the rectum is a rare disease, and surgery seems to be a good option of treatment, with the possibility of sphincter preservation depending upon the location of the tumor.
authors.affiliation: Dept of Surgery, Instituto Nacional de la Nutricion Salvador Zubiran, Mexico City, México, D.F.
authors.forename: M D
authors.initials: MD
authors.lastname: Martinez-Gonzalez
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: E
authors.initials: E
authors.lastname: Leon-Rodriguez
authors.forename: A
authors.initials: A
authors.lastname: Gamboa-Dominguez
authors.forename: C
authors.initials: C
authors.lastname: Lome
authors.forename: M C
authors.initials: MC
authors.lastname: Garcia-Blanco
authors.forename: P
authors.initials: P
authors.lastname: Bezaury
authors.forename: M A
authors.initials: MA
authors.lastname: Moran
mesh_terms: D000328:Adult; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000628:therapy; D005260:Female; D006801:Humans; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000628:therapy