Response to bipolar androgen therapy and PD-1 inhibition in a patient with metastatic castration-resistant prostate cancer and a germline CHEK2 mutation.

We present the case of a patient with germline CHEK2-mutated metastatic castration-resistant prostate cancer (mCRPC) who responded to bipolar androgen therapy (BAT) combined with pembrolizumab after progressing through multiple lines of therapy. The patient was diagnosed in his 40s following an elevated screening prostate-specific antigen and biopsy. Over the course of 20 years, he progressed through nearly all standard therapies including androgen deprivation, combined androgen blockade, traditional chemotherapy, targeted therapies and experimental agents. He was ultimately treated with BAT, whereby the patient's cycle was between low (castrate) and high (supraphysiological) testosterone levels. This counterintuitive approach resulted in a marked response to BAT plus pembrolizumab consolidation lasting 13 months. His underlying germline mutation in CHEK2, an important mediator of DNA repair, may have sensitised the cancer cells to the DNA damage caused by BAT. Single case report outcomes should not be used as evidence of efficacy for treatment regimes. Our case supports further investigation into BAT plus immunotherapy for patients with DNA repair-deficient mCRPC.

Mucor and Malignancy: A Double-Hit Case of Intestinal Ischemia.

Mucormycosis is an invasive fungal infection due to molds in the order Mucorales. These opportunistic pathogens found in soil or decaying organic matter mostly affect immunocompromised hosts. Rhino-orbital-cerebral, pulmonary, gastrointestinal, cutaneous, and disseminated patterns are possible. We describe a case of angioinvasive colonic mucormycosis in a patient with recent diabetic ketoacidosis and undiagnosed colon adenocarcinoma. The diagnosis was made on histopathology after the patient developed intestinal ischemia and underwent hemicolectomy. This case highlights the potentially diverse manifestations of Mucorales infections, typical and atypical risk factors, and the index of suspicion necessary for early diagnosis and outcome optimization.