A modified technique for intralesional injection of collagenase Clostridium histolyticum for Peyronie's disease results in reduced procedural morbidity using a standardized hematoma classification rubric

Purpose Early clinical trials of injectable collagenase Clostridium histolyticum (CCh) for Peyronie's disease (PD) demonstrated safety and efficacy. Since then, modified injection protocols have been proposed. Adverse events-such as bruising, swelling, hematoma, and corporal rupture-exceed 50% in many studies, but lack of standardization of hematoma severity limits conclusions about the relative safety of protocols. We propose a modification of the standard injection technique that aims to decrease the rates of adverse events. We further describe a hematoma classification rubric that may standardize safety assessment. Methods A modified injection procedure, termed the "fan" technique, was employed in the treatment of PD. All men receiving CCh from January 2016 through January 2019 at a single institution were included in an institutional review board (IRB) approved database. Treatment outcomes and adverse events were retrospectively assessed. A three-tiered hematoma classification rubric was devised to standardize reporting of hematoma, which was defined as concurrent bruising and swelling at the site of injection without loss of erection. Results Using the fan technique, 152 patients received 1323 injections. Eight hematomas (5.3% of all patients, 0.6% of all injections) were observed. The number of grade I, grade II, and grade III hematomas were 3, 2, and 3, respectively. Bruising or swelling not meeting the definition of hematoma was seen in 54.6% and 27.0% of patients, respectively. There were zero corporal ruptures. Conclusion A modified injection technique results in reduced procedural morbidity. A hematoma classification system provides clarity and standardization to the assessment of safety in PD treatment. Further clinical studies with control arms are required to verify these findings.