History: A 56-year-old woman presented to a primary care physician with a three month history of intermittent bright red rectal blood with defecation. Examination: Rectal examination, anoscopy, and a pelvic examination with DNA testing for high-risk human papillomavirus (HPV) were performed; all results were negative. She was referred for a colonoscopy. Colonoscopy revealed an abnormal area with a 3 × 4 cm mass in the rectum at a distance of 10 cm from the anal verge.
Colonoscopic biopsy of this mass revealed invasive squamous cell carcinoma (Cover image 1A and 1B). p16 immunohistochemistry staining of the biopsy specimen showed positive results (Cover image 1C). Staging workup with a total body CT scan (Cover image 2A) and positron emission tomography (PET)/CT scan (Cover image 2B) confirmed the presence of a rectal mass, which demonstrated a standardized uptake value of 10. There was…
