An Integrated Approach to MSI-High Colorectal Cancer Therapy in a Young Patient: A Clinical Case.
Innara Turkpenova, Kaldygul Smagulova, Abay Jumanov et al.
✦ AI-curated · Sources linked
Case in brief
A 16-year-old male underwent appendectomy for presumed appendicitis, but persistent postoperative bowel obstruction led to CT detection of a descending-colon tumor and emergency Hartmann’s procedure. Pathology showed mucinous adenocarcinoma, pT4N0M0, with vascular invasion. Tumor testing found loss of MSH2/MSH6 with retained MLH1/PMS2, indicating deficient mismatch repair and findings highly suggestive of Lynch syndrome; germline testing was unavailable. A KRAS mutation was identified, with no NRAS alteration. He received 12 cycles of adjuvant FOLFOX and remained disease-free more than 5 years after treatment.
What made this case unusual
The cancer presented in adolescence as persistent bowel obstruction after surgery for presumed appendicitis. Loss of MSH2/MSH6 suggested Lynch syndrome, but germline testing was unavailable.
Diagnostic / clinical pearl
Persistent or atypical abdominal symptoms in a young patient warrant consideration of colorectal malignancy. MMR/MSI testing can identify tumor features that raise concern for a hereditary cancer syndrome.