Primary synchronous rectal squamous-cell carcinoma and its exceptional response to chemoradiotherapy

We present the case of a 51-year-old female with a 2-month history of intense anal pain and rectal bleeding. A digital rectal exam revealed a possible lower rectal mass. A colonoscopy was then performed that showed a 5 x 6-cm lesion in the middle rectum and a second 3-cm lesion in the lower rectum, without affecting the anal canal. Multiple biopsies were taken and the histopathologic analysis revealed a moderately differentiated squamous-cell proliferation invading beyond the lamina propria. The CT scan confirmed a middle rectum T4N2bM0 and a lower rectum T3N0M0 synchronous neoplasia. These findings were compatible with a synchronous squamous-cell carcinoma (SCC).