What happened, in summary

A 58-year-old woman with diabetes, hypertension, and hypothyroidism was diagnosed with moderately differentiated rectal adenocarcinoma by endoscopy and biopsy. Imaging suggested locally advanced disease. She was highly anxious about the diagnosis, prognosis, and family responsibilities. Neoadjuvant treatment combined capecitabine with radiotherapy at 200 cGy for 28 days, followed by anterior resection with primary anastomosis and a covering ileostomy. Her immediate postoperative recovery was uncomplicated.

Two weeks after surgery, painful excoriation developed around the ileostomy and abdominal incision. Barrier products, antimicrobial creams, zinc-based powders, and specialist stoma care did not stop the lesions from spreading. The stoma remained healthy and functional without leakage, but the skin disease extended across the abdominal wall. Because contact dermatitis was initially suspected, the ileostomy was reversed early on day 48. Blistering nevertheless continued across the abdomen, back, and trunk.

Dermatology review and biopsy led to a diagnosis of pemphigus vulgaris. Prednisolone produced an initial improvement, but the lesions returned when the dose was reduced. She then received two 1 g doses of rituximab 15 days apart. The skin healed gradually with residual pigmentation, and the pemphigus remained in remission 14 months later. During the skin workup, clinicians described no evidence of residual internal malignancy. The case separates a serious postoperative autoimmune skin disorder from the rectal-cancer treatment and outcome.