Transcervical needle biopsy for the differential diagnosis between uterine sarcoma and leiomyoma

The clinical differential diagnosis between uterine sarcoma and benign leiomyoma is difficult even with magnetic resonance imaging (MRI). Therefore, a considerable number of patients have undergone hysterectomies due to an indication of "suspected malignancy" based on tumor size alone. However, approximately 80% of these hysterectomies have been judged to have been recommended inappropriately. In such situations, reliable preoperative diagnostic tests are required. The authors have evaluated the accuracy of needle biopsy for uterine myoma-like tumors, a procedure that to the authors' knowledge has been performed infrequently.

Transcervical needle biopsy was performed in 435 patients with uterine myoma-like tumors. The biopsy specimens were scored for degree of malignancy according to the histopathologic criteria proposed by Bell et al. Histopathologic evaluation of surgical specimens and clinical outcome after 2 years of follow-up were used as the reference standards.

Of 435 patients, 7 had uterine sarcomas, 4 of which were scored as > or = 4 points and were diagnosed as "sarcoma" by needle biopsy alone. No sarcoma cases were included in the group of patients with a score of 0. The cutoff score combining the highest sensitivity and specificity with respect to distinguishing uterine leiomyosarcoma from uterine leiomyoma was 2; sensitivity, specificity, and positive and negative predictive values were 100%, 98.6%, 58%, and 100.0%, respectively.

Transcervical needle biopsy using histopathologic scoring is a reliable diagnostic test for the differential diagnosis between uterine sarcoma and leiomyoma. This diagnostic method, combined with MRI screening, could reduce the number of patients currently undergoing unnecessary surgery.