Guillain-Barré Syndrome following intravesical Bacillus Calmette-Guérin therapy for bladder cancer: a rare and intriguing case report.

Intravesical Bacillus Calmette-Guérin (BCG) therapy is a standard treatment for non-muscle invasive bladder cancer, but some patients experience side effects that lead to treatment discontinuation. Local side effects are typically mild, while systemic side effects can be severe and life-threatening. BCG therapy has immunotherapy effects on bladder cancer, but the mechanism is not fully understood. Due to its effect on the immune system, patients may also develop rare autoimmune complications, such as neuropathy. This case report suggests a potential association between BCG therapy and Guillain-Barré Syndrome (GBS), as a patient developed GBS after receiving intravesical BCG therapy for invasive bladder cancer.

Linitis plastica of the rectum secondary to metastatic prostate cancer: A case report of a rare presentation and literature review.

Linitis plastica is a rare tumor with poor prognosis. It is a circumferentially infiltrating intramural tumor which can result in rigid, nondistensible thickening of the affected organ. It most commonly affects the stomach, followed by the rectum, and can be due to primary or secondary cancer. Secondary rectal linitis plastica (RLP) caused by metastatic cancers has been reported from the stomach, breast, gallbladder, urinary bladder, and very rarely, the prostate, with only <5 reported cases in the literature. We report the case of a 66-year-old man who presented with altered bowel habit and loss of weight, with elevated prostate-specific antigen of 180.6 ng/mL. Sigmoidoscopy showed thickened rectal mucosa, and biopsy was negative for malignancy. Magnetic resonance imaging showed circumferential wall thickening, "target sign" appearance suggestive of RLP, PIRADS 5 lesion with extraprostatic extension, infiltrating bilateral seminal vesicles, and right neurovascular bundle. Repeat colonoscopy was performed under anesthesia, and deeper biopsy revealed poorly differentiated metastatic prostate adenocarcinoma. This case report highlights the atypical presentation of metastatic prostate cancer secondary to RLP, the rarity of this condition, and emphasizes the importance of deeper biopsy in RLP due to disease involvement predominantly in the submucosa and muscularis propria layers.