Unexpected Malignancy in Women Undergoing Surgery for Uterine Fibroids

Fibroids are the most common tumors of the uterus and female genital tract. There are several treatment modalities for fibroids, spanning from watchful waiting, medical management, and surgical management, of which surgery continues to be the mainstay of treatment. It has been observed that in a few rare cases, what are presumed to be fibroids preoperatively can reveal malignancy in histopathology, the consequences of which can be grave.

The primary objective of this study was to estimate the prevalence of unexpected uterine malignancy in women undergoing surgery for uterine fibroids. The secondary objective was to study the clinical characteristics of patients with such unexpected uterine malignancy detected on histopathology.

We conducted an observational study including all patients who underwent myomectomy or hysterectomy, by any route, for uterine fibroid at the Department of Obstetrics and Gynecology, Maulana Azad Medical College and Lok Nayak Hospital, New Delhi. Any case with preoperative diagnosis of endometrial hyperplasia with atypia or any suspected malignancy was excluded. Data were collected over a period of three years from gynecologic operation theatre records, histopathology reports, and patient files. The prevalence of unexpected uterine malignancy was estimated overall.

A total of 436 women underwent surgery for uterine fibroids in our study; among them, three cases of unexpected malignancy and two cases of smooth muscle tumours of uncertain malignant potential (STUMP) were identified, thus making the prevalence of 0.68% for unexpected uterine malignancy in fibroids.

The absolute risk of unexpected malignancy in women with fibroids is low, but the difficulty in preoperative diagnosis remains a challenge. Hence, patients should be counselled preoperatively about the likelihood of such a finding in the final histopathology.