Mature cystic teratoma: a clinicopathologic evaluation of 517 cases and review of the literature.

OBJECTIVE

To evaluate the clinical and pathologic presentation of mature cystic teratomas and the trends in management over a 14-year study period.

METHODS

Tumor registry data and medical records between January 1, 1975 and December 31, 1989 were analyzed with respect to patient age, tumor size, bilaterality, malignant transformation, and treatment.

RESULTS

Five hundred seventy-three tumors were removed from 517 patients. The median and mean (+/- standard deviation) age was found to be 30 and 32 +/- 11.3 years, respectively. Three hundred ten (60%) of the patients were asymptomatic. The mean tumor size was 6.4 +/- 3.5 cm. The bilaterality rate was 10.8%. The rate of torsion was 3.5%; larger tumors underwent torsion more frequently than smaller tumors (P = .029). The rate of malignant transformation was 0.17%. The mean cyst diameter for patients undergoing cystectomy was 5.7 +/- 2.4 cm; for oophorectomy, 8.0 +/- 4.1 cm; and for hysterectomy, 6.1 +/- 3.8 cm. Oophorectomies were performed for larger tumors when compared to cystectomies (P = .01). The number of hysterectomies was stable throughout the study period, whereas the number of oophorectomies decreased and the number of cystectomies increased markedly. Contralateral ovarian biopsy was common (48.5%) early in the study period. By 1989, the biopsy rate was less than 1%.

CONCLUSIONS

We found the prevalence rates of symptomatic tumors, torsion, and malignant degeneration to be less than those previously reported by most other investigators. In addition, there has been an important change over the past 14 years in the management of these neoplasms, with an increased tendency for ovarian preservation, as evidenced by the more frequent use of cystectomy and a decrease in contralateral ovarian biopsy.