Extrusion of testosterone pellets: a randomized controlled clinical study

BACKGROUND It has previously been shown that testosterone implantation is a n effective and well accepted form of androgen replacement therapy, but tha t pellet extrusion was the most frequent side-effect. The present study aim ed to reduce the extrusion rate. OBJECTIVE To determine whether the washing of testosterone pellets to remov e potentially surface-adherent particles decreased the rate of extrusion of pellet implants. DESIGN Prospective, randomized parallel group design in a single centre wit h consecutive procedures to be randomized (1 :1) into a wash or control gro up. PATIENTS The study included 251 testosterone implantation procedures in men with known androgen deficiency. MEASUREMENTS The primary endpoint, extrusion rate per procedure, was evalua ted prospectively by telephone contact at 1 week and then 3 and 6 month int ervals. Secondary end-points included peri-procedure adverse events (bleedi ng, skin reaction, excessive discomfort) noted at the time of implant. Brui sing, bleeding and infection were also evaluated as later adverse events by telephone and personal follow-up. Explanatory variables recorded as possib le covariables included the number of implants used, production batch numbe r of the implants, the operator, as well as other demographic and medical f actors. RESULTS In the wash group, the extrusion rate was 12% per procedure (19 pel lets from 15 subjects) whereas in the control group, the extrusion rate was 11.1% per procedure (18 pellets from 14 subjects), indicating no evidence of any benefit of the wash procedure (OR=1.09 [95% Cl 0.47-2.6] per procedu re), There was no evidence of benefit in secondary endpoints including tota l adverse events (7.1%, OR 1.28 [0.44-3.9], bleeding/bruising (8.8%, 1.23 [ 0.47-3.3]) and infection (4.0%, 1.54 [0.35-7.6]) per procedure. Among men r eporting an infection requiring antibiotic treatment according to their own general practitioners, six/ten (60%) subsequently experienced an extrusion . There were no significant differences in extrusion rate between four diff erent operators (P=0.24) nor among 12 different batches of pellets used dur ing the course of the study (P=0.77). CONCLUSIONS The pellet washing procedure used during implantation does not reduce the subsequent extrusion rate. The higher rate of both primary and s econdary adverse events in this prospective study compared with the previou s retrospective survey may reflect either more rigorous follow-up or a secu lar trend.