Fournier’s Gangrene after Radiation Therapy for Rectal Carcinoma: A Rare Case Description and Review of Literature

Background: Fournier's Gangrene (FG) is a rapidly progressive infective necrotizing fasciitis primarily affecting the genital region1. It is predominantly associated with various urological, gastrointestinal, and retroperitoneal diseases, some of which may involve malignancies of these regions2. The occurrence of Fournier's gangrene following radiation therapy for an underlying carcinoma is exceedingly rare, and therefore, only sporadic cases have been documented in the literature. Treating Fournier's gangrene in this specific context presents increased complexity compared to cases stemming from other causes, and it is associated with elevated mortality rates3. Consequently, a heightened level of vigilance is necessary in the management of such cases. In this report, we present the case of a 71-year-old male patient diagnosed with rectal carcinoma who developed Fournier's Gangrene subsequent to radiotherapy, and the treatment approach was tailored accordingly. Case Description: A 71-year-old male presented to our department with a chief complaint of persistent rectal bleeding for a duration of one year. Further assessment, including a contrastenhanced computed tomography (CECT) scan of the entire abdomen and pelvis, revealed a 5.4x4.7x4.5 cm lesion located in the ano-rectal region. Due to the patient's compromised overall health status, a decision was made to administer palliative external beam radiotherapy (EBRT) to the pelvic region. The treatment plan consisted of a total radiation dose of 20 Gy delivered over five fractions spanning five consecutive days (20 Gy/5 fraction/5 days), employing anteriorposterior (AP) and posterior-anterior (PA) fields. Shortly after the completion of radiotherapy, the patient developed severe bilateral swelling of the scrotum, which subsequent evaluation confirmed to be Fournier's gangrene. Prompt surgical intervention in the form of incision and drainage, in conjunction with intravenous administration of appropriate antibiotics, was performed, yielding positive a therapeutic outcome. Currently, the patient is being maintained on a low-dose oral metronomic chemotherapy regimen with tablet Capecitabine at a dose of 500 mg twice daily for a duration of two weeks, followed by a one-week treatment-free interval. The patient has demonstrated favorable response and tolerability to the prescribed treatment regimen, given the presence of residual disease. Conclusion: We report an extremely rare case of development of Fournier’s Gangrene following Radiotherapy in a case of Carcinoma Rectum which can be associated with very high mortality if not diagnosed early and treated properly. Hence, prompt diagnosis and aggressive management of this rare complication is necessary for patient’s favorable outcome.