Urinary Pubic Symphysis Fistula Leads to Histopathologic Osteomyelitis in Prostate Cancer Survivors

Objectives To assess the histologic findings in the pubic bone resected during extirpative surgery for urinary pubic symphysis fistula (UPF). The concurrent presence of osteomyelitis and the need for bone resection at time of extirpative surgery for UPF has been debated. We hypothesized that UPF results in histopathologically confirmed osteomyelitis, underscoring the importance of bone resection at the time of surgery. Methods An IRB approved retrospective review of all patients undergoing surgery for UPF from 2012 to 2019 was performed. Demographic data were recorded. A single pathologist performed histopathologic examination of bone tissue in each case. Logistic regression and Fisher exact test were used to assess association of osteomyelitis with clinical factors. Results We identified 36 patients who underwent major extirpative surgery for UPF with bone pathology available for review. Bone histopathology findings confirmed presence of osteomyelitis in the majority (n=32, 88.9%). This was characterized as chronic osteomyelitis in 15 (41.7%), acute osteomyelitis only in 1 (2.8%) and combined chronic and acute osteomyelitis in 16 (44.4%). Osteonecrosis was seen in 11 cases (33.6%). There was no correlation between presence of osteomyelitis and age, timing from radiotherapy to diagnosis of UPF, type of radiotherapy, or history of endoscopic bladder outlet procedures. Conclusions Osteomyelitis is present on histology of the pubic bone resected during surgery for UPF in the majority of cases (88.9%). Osteonecrosis is also common. These findings underscore the critical importance of pubic bone resection at time of UPF surgery to adequately treat the diseased bone.