Factors Associated with Replacement Interval and Complications of Provox Voice Prostheses in Post-Laryngectomy Patients: A Single-Center Retrospective Recurrent-Event Analysis

Background/Objectives: Indwelling tracheoesophageal prostheses have a limited lifespan and require repeated replacement. We examined the determinants of the replacement interval. Methods: This study conducted a retrospective single-center analysis of 147 consecutive Provox replacements in 82 laryngectomized patients (June 2024–February 2026), reported according to STROBE, using mixed-effects and gap-time recurrent-event models. Results: Median device survival was 141 days. Prior irradiation was associated with a shorter interval (−38.3 days; 95% CI −67.2 to −9.3; p = 0.010), with a gradient by treatment intensity: the median survival was 179, 136, and 84 days after primary surgery, radiotherapy alone, and chemoradiotherapy (log-rank p < 0.001; cluster-robust hazard ratios 2.19 and 5.13 against primary surgery). A higher cumulative replacement burden—in terms of lifetime exchanges per patient, with a median of eight and range of 1–28—was also associated with shorter intervals (β = −3.70 days per additional lifetime exchange; 95% CI −5.84 to −1.57), but it summarizes the same event process as the outcome and is reported as a phenotype marker. Intervals ending in elective exchange were longer (β = 35.47 days; 95% CI 15.80 to 55.14), but in the primary recurrent-event model, containing only covariates fixed at interval start and retaining censored intervals, elective placement showed no association with device lifetime (HR 0.574; 95% CI 0.309–1.066; p = 0.079); between-patient heterogeneity remained substantial (θ = 0.452; p = 0.002). Complications occurred in seven of 147 procedures (4.8%), which were all managed without life-threatening events. Conclusions: Prior oncological treatment, particularly chemoradiotherapy, is associated with materially shorter device survival and can be used to identify patients likely to require more frequent exchange. Outpatient exchange appears safe. The association between elective replacement and longer intervals reflects conditioning inherent in comparing scheduled with failure-driven exchange, not a benefit of scheduling.