Early versus late maturation arrest: incidence and clinical significance in testicular failure

Abstract

OBJECTIVE: There is a paucity of data in the literature characterizing the stages of maturation arrest (MA). We hypothesize that patients with earlier MA have a higher serum FSH reflecting increased sertoli cell/testicular damage and that the probability of mature sperm extraction increases at later stages of MA. DESIGN: All patients undergoing sextant site-specific testis biopsies, i.e. testis mapping, at a single institution from 2004-2008 were retrospectively reviewed. MATERIALS AND METHODS: 114 patients with nonobstructive azoospermia (NOA) and 23 patients with severe oligospermia (density < 10,000 sperm/mL) were categorized by their major, and if present, minor histopathology patterns. These categories consisted of sertoli-cell only (SCO), early maturation arrest (EMA), late maturation arrest (LMA), hypospermatogenesis (H) and normal. EMA was characterized by maturation arrest up to the level of the primary spermatocyte and LMA up to the level of the spermatid. Each group was analyzed with respect to serum hormone concentration, testicular volume, chromosomal abnormalities (karyotype, Y-deletions) and presence of sperm at the time of testicular mapping. Statistical analysis was carried out by paired T-test. RESULTS: 42 (30.9%) patients were identified with MA. 15 patients had concomitant SCO histology. Pathology was organized according to primary and secondary components (Table 1). Mean FSH of pure EMA versus pure LMA was 16.2 vs. 6.8 (p = 0.037). FSH correlated with testis pathology (Table 1) but not with the probability of obtaining sperm at the time of biopsy (p = 0.32). The frequency of successful sperm extraction during testis mapping increased with later stages of MA (SCO/mixed MA = 26.7%, EMA = 14.3%, mixed MA = 37.5%, LMA = 46.1%). Y-chromosome deletions were detected in 35.7% of patients with EMA, 14.2% with LMA, and 2.1% of all other patients.Table 1Histopathologic categoriesSCOSCO/EMASCO/LMAEMAEMA/LMALMA/EMALMAN428774413FSH29.324.225.316.2115.36.8% pts with sperm extracted7.12528.614.2502546.2 Open table in a new tab CONCLUSIONS: MA is a common pattern in NOA that is frequently associated with other histopathology. In patients with pure MA, FSH is higher in patients with EMA and tends to decrease and approach normal with later stages of spermatogenesis present. We also report that a higher percentage of patients with EMA have Y-chromosome microdeletions. Although FSH did not correlate with the probability of sperm extraction, the probability of sperm found on testis mapping was higher with late maturation arrest.