The tumor grows as a large, soft, polypoid mass, filling and distending the uterine cavity; necrosis and hemorrhage are prominent features. The myometrium is invaded to various degrees in almost all cases. The most frequent areas of spread are the pelvis, lymph nodes, peritoneal cavity, lungs, and liver. This metastatic pattern suggests that these neoplasms spread by local extension and regional lymph node metastasis in a manner similar to that of endometrial adenocarcinoma, although they behave more aggressively.
The most important single factor affecting prognosis in patients with carcinosarcoma is the extent of tumor at the time of treatment. One study noted that in patients with tumor apparently confined to the uterine corpus (stage I), the 2-year survival rate was 53%, whereas the survival rate dropped to 8.5% when disease had extended to the cervix, vagina, or parametria (stage II and III); no patients with disease outside the pelvis (stage IV) survived (445). In another study, 5-year survival for patients with disease confined to the corpus (74%) was significantly greater than for those with more advanced disease (24%) (446).
Disease extends outside the uterus in 40% to 60% of cases at the time of diagnosis, indicating the highly malignant nature of this lesion. Even when disease is believed to be confined to the uterus preoperatively, surgical and pathologic staging identifies extrauterine spread of disease in a significant number of cases. In one study, 55% of women with clinical stage I carcinosarcoma had a higher surgical–pathologic stage. Only 28% of tumors were actually confined to the uterine corpus, 16% had extension to the cervix, and 56% showed extrauterine spread (447). In a significant number of patients, lymph node metastases and positive peritoneal cytology werefound with early-stage carcinosarcoma (446,448,449). Deep myometrial invasion, which is present in about one-half of stage I cases, is associated with poor prognosis. Almost all patients in whom tumor involves the outer one-half of the myometrium die from the disease. Patients who die from carcinosarcoma tend to have larger tumors and a higher incidence of LVSI. Patients with a history of prior pelvic radiation have a poorer prognosis. Overall, the 5-year survival rate for patients with carcinosarcoma is about 20% to 30%.
Adenosarcoma is an uncommon variant of carcinosarcoma (450,451). It consists of an admixture of benign-appearing neoplastic glands and a sarcomatous stroma. Most patients present with postmenopausal vaginal bleeding, and the disease is diagnosed or suspected based on endometrial curettage. Most adenosarcomas are well circumscribed and limited to the endometrium or superficial myometrium. The treatment is hysterectomy and bilateral salpingo-oophorectomy, with or without adjuvant radiotherapy. Because recurrences, mostly in the form of local pelvic or vaginal disease, are reported in 40% to 50% of cases, adjuvant postoperative intravaginal or pelvic radiation is recommended.
Treatment Recurrences develop in more than one-half of cases of uterine sarcoma, even when disease is apparently localized at the time of treatment (452–454). At least one-half of recurrences occur outside the pelvis, with isolated pelvic failures accounting for less than 10% of recurrences. The most common sites of recurrence are the abdomen and lungs. These data emphasize that the major limitation to cure of uterine sarcomas is distant spread.