Presentation
Presents a few months post chemoradiotherapy for rectal tumor.
Patient Data
Lower rectum tumor that, although the history of previous chemotherapy/radiotherapy, is made mostly by intermediate to high T2 signal and shows restricted diffusion. It involves the CRM and invades the left seminal vesicle.
The tumor is mostly at the inferior rectum with perhaps involvement of the anorectal junction. Peritoneal reflection is 6 mm above the upper limits of the mass.
No locoregional or metastatic suspicious lymph nodes.
Biopsy was performed:
Macroscopy: Rectal biopsy: 5 pale tan pieces of tissue 4-8 mm.
Microscopy: The sections show squamous glandular mucosa including a moderate amount of subepithelial connective tissue. Multiple irregular nests of moderate to markedly pleomorphic epithelial cells are seen, containing a small amount of cytoplasm, nuclear hyperchromasia and small nucleoli. There are frequent atypical mitoses and apoptosis. There is associated desmoplastic stroma. No convincing lymphovascular or perineural invasion is identified.
Conclusion: Poorly differentiated squamous cell carcinoma.
Mass lesion at the lower rectum/anal canal region with marked uptake and impression of invasion of the left seminal vesicle.
Case Discussion
This case illustrates tumor recurrence/progression of a lower rectum tumor with extramural extension and invasion of the left seminal vesicle (T4 disease). Pre chemoradiation imaging (not available) showed a much smaller tumor at the anorectal region.
The recurrent tumor is centered in the lower rectum with perhaps reaching the anorectal junction at its inferior components. Primary rectal SCC is uncommon. Squamous cell carcinoma of the gastrointestinal tract usually involves the esophagus or the anal canal.