CYSTOSARCOMA-PHYLLODES IN ADOLESCENT GIRLS AND YOUNG-WOMEN - A STUDY OF 45 PATIENTS

Cystosarcoma phyllodes (CP) is an uncommon tumor in adolescent girls a nd young women. This study seeks to define the clinical and pathologic features of CP in this unusual clinical setting. Forty-five CPs (34 b enign and 11 malignant) in prepubertal and adolescent girls and young women were studied. Classification of the tumors was based on the foll owing morphologic features: stromal cellularity, nuclear atypia, mitot ic activity, necrosis, and the nature of tumor borders. Surgical thera py was local excision or mastectomy. The age of the patients ranged fr om 10 to 24 years (mean 17.7). The tumors measured 1.4 cm to 10.2 cm a t their widest point (mean 4.6). Both breasts were affected equally. T hirty-two patients were treated by local excision with or without reex cision and four patients by mastectomy. Follow-up was available for 36 patients for a mean of 58.4 months. Local recurrence was reported in six of the 36 cases (16%) (four benign and two malignant). The six pat ients with recurrent disease had infiltrative tumor borders and positi ve surgical margins microscopically. There was a single instance of sy stemic metastases from a high-grade malignant tumor with rhabdomyosarc omatous stromal differentiation and a high mitotic rate. At last follo w-up, 34 patients were alive with no evidence of disease,one patient w as alive with pulmonary metastases, and one patient died of an unrelat ed cause. We concluded that CP in adolescent girls and young women is not more aggressive than in older patients. Infiltrative tumor borders and positive surgical margins are the best histologic predictors for local recurrence. Mitotic activity is the most important criterion for assessing the metastatic potential. CP in this age group should be tr eated to maximize breast conservation. Mastectomy may be required to o btain clear margins for CPs that cannot be managed by excision because of large tumor size relative to breast volume.