Morphological variants and secondary changes in uterine leiomyomas Is it important to recognize them?

Abstract

Background: Uterine leiomyomas are common tumours of the female genital tract and may be responsible for significant morbidity. These tumours are benign, but some of the variants and secondary changes may create diagnostic difficulties. Objectives : This study was conducted to identify the secondary changes and variants of leiomyomas, especially those mimicking malignancy and to assess the histopathological features which help to differentiate them from malignant tumours. Method : Hysterectomy and myomectomy specimens received over a period of two years were studied. Detailed gross and microscopic examination of the leiomyomas was done. Results: 200 specimens (hysterectomy and myomectomy) were studied in which 545 leiomyomas were examined (seedling leiomyomas were excluded). Ages of patients ranged from 20 years to 72 years with peak incidence in the 4^th decade. Secondary changes were observed in 24.2% cases and histological variants comprised 7.5% of the cases. The histological variants which posed diagnostic difficulties were cellular leiomyomas, atypical leiomyoma, epithelioid leiomyoma, and leiomyomas with secondary changes including haemorrhagic infarction, myxoid change and perinodular hydropic change. Conclusion: Uterine leiomyomas are common benign tumours in gynaecological histopathology specimens. However, secondary changes and morphological variants especially those with increased cellularity, increased mitoses and nuclear atypia create diagnostic problems. A thorough examination and adherence to the standard diagnostic criteria is required to rule out malignancy.