Note: Separate PDQ summaries on Endometrial Cancer Treatment, Screening for Endometrial Cancer, Prevention of Endometrial Cancer, and Adult Soft Tissue Sarcoma are also available.
Uterine sarcomas comprise less than 1% of gynecologic malignancies and 2% to 5%
of all uterine malignancies. These tumors arise primarily from two distinct
tissues: 1) leiomyosarcoma from myometrial muscle and 2) mesodermal (mullerian)
and stromal sarcomas from endometrial epithelium. The only documented
etiologic factor in 10% to 25% of these malignancies is prior pelvic radiation therapy,
often administered for benign uterine bleeding 5 to 25 years earlier.
The prognosis for patients with uterine sarcoma is primarily dependent on the extent of
disease at the time of diagnosis. For carcinosarcomas (mixed mesodermal
tumors), isthmic or cervical location, lymphatic vascular space invasion,
serous and clear cell histology, and grade 2 or 3 carcinoma are all significant
predictors of metastatic disease at initial surgery. These factors, along
with adnexal spread, lymph node metastases, tumor size, peritoneal cytologic
findings, and depth of myometrial invasion correlate with progression-free
interval. The presence or absence of stromal heterologous elements, the
types of such elements, the grade of the stromal components, and the mitotic
activity of the stromal components bear no relationship to the presence or
absence of metastases at surgical exploration. However, in one study, women
with a well-differentiated sarcomatous component or carcinosarcoma had
significantly longer progression-free intervals than those with moderate- to
poorly differentiated sarcomas for both the homologous and heterologous types.
The recurrence rate was 44% for homologous tumors and 63% for heterologous
tumors. The type of heterologous sarcoma had no effect on the progression-free
interval. For leiomyosarcomas, some consider tumor size to be the most
important prognostic factor; patients with tumors greater than 5.0 centimeters in maximum
diameter have a poor prognosis. However, in a Gynecologic Oncology Group
study, the mitotic index was the only factor significantly related to
progression-free interval. Leiomyosarcomas matched for other known
prognostic factors may be more aggressive than their carcinosarcoma
counterparts. The 5-year survival for patients with stage I disease
confined to the corpus is approximately 50% versus 0% to 20% for the remaining
Surgery alone can be curative if the malignancy is contained within the uterus.
The value of pelvic radiation therapy is not established. Current studies consist
primarily of Phase II chemotherapy trials for advanced disease. Adjuvant
chemotherapy following complete resection (stage I and II) has not been
established to be effective in a randomized trial. Yet, other nonrandomized
trials have reported improved survival following adjuvant chemotherapy with or
without radiation therapy.[6,7,8]
- Forney JP, Buschbaum HJ: Classifying, staging, and treating uterine sarcomas. Contemp Ob Gyn 18(3):47, 50, 55-56, 61-62, 64, 69, 1981.
- Major FJ, Blessing JA, Silverberg SG, et al.: Prognostic factors in early-stage uterine sarcoma. A Gynecologic Oncology Group study. Cancer 71 (4 Suppl): 1702-9, 1993.
- Evans HL, Chawla SP, Simpson C, et al.: Smooth muscle neoplasms of the uterus other than ordinary leiomyoma. A study of 46 cases, with emphasis on diagnostic criteria and prognostic factors. Cancer 62 (10): 2239-47, 1988.
- Oláh KS, Dunn JA, Gee H: Leiomyosarcomas have a poorer prognosis than mixed mesodermal tumours when adjusting for known prognostic factors: the result of a retrospective study of 423 cases of uterine sarcoma. Br J Obstet Gynaecol 99 (7): 590-4, 1992.
- Omura GA, Blessing JA, Major F, et al.: A randomized clinical trial of adjuvant adriamycin in uterine sarcomas: a Gynecologic Oncology Group Study. J Clin Oncol 3 (9): 1240-5, 1985.
- Piver MS, Lele SB, Marchetti DL, et al.: Effect of adjuvant chemotherapy on time to recurrence and survival of stage I uterine sarcomas. J Surg Oncol 38 (4): 233-9, 1988.
- van Nagell JR Jr, Hanson MB, Donaldson ES, et al.: Adjuvant vincristine, dactinomycin, and cyclophosphamide therapy in stage I uterine sarcomas. A pilot study. Cancer 57 (8): 1451-4, 1986.
- Peters WA 3rd, Rivkin SE, Smith MR, et al.: Cisplatin and adriamycin combination chemotherapy for uterine stromal sarcomas and mixed mesodermal tumors. Gynecol Oncol 34 (3): 323-7, 1989.