Malignant phyllodes tumor with chondrosarcomatous differentiation: report of a case with cytological presentation

Malignant phyllodes tumor of the breast with heterologous osteosarcoma and chondrosarcomatous differentiation: A rare case report with imaging findings

Phyllodes tumors of the breast are rare fibroepithelial neoplasms accounting for 0.3%-1.5% of all female breast tumors [1,2]. Malignant transformations occur in 10%-20% of phyllodes tumors, often in the form of stroma. Heterologous osteosarcoma and chondrosarcomatous differentiation of phyllodes tumor are extremely rare, and little is known about their imaging findings. Here, we report a rare case of a 52-year-old woman with no history of previous surgery or radiation therapy, who presented with a rapidly growing right breast mass that was diagnosed as a malignant phyllodes tumor with heterologous osteosarcoma and chondrosarcomatous differentiation. The patient underwent modified radical mastectomy.

Phyllodes tumour with heterologous sarcomatous differentiation: Case series with literature review

INTRODUCTION

Phyllodes tumours are rare fibroepithelial malignancies of the breast, accounting for less than 1% of malignant breast tumours. Further malignant differentiation of phyllodes tumours can occur, resulting in cases of extremely rare heterologous sarcomatous differentiation.

PRESENTATION OF CASE

Two females in their fifties were diagnosed with malignant phyllodes tumour associated with heterologous sarcomatous differentiation. The first patient, aged 50 had phyllodes tumour with chondrosarcoma, osteosarcoma and ductal carcinoma-in-situ. The second patient, aged 53 had phyllodes tumour with osteosarcoma and liposarcoma.

DISCUSSION

The association of phyllodes tumour and heterologous sarcomatous differentiation is rare, with only 4 previously reported cases in English literature. The paucity of evidence presents challenges in its management with uncertain prognosis and monitoring requirements for two aforementioned patients.

CONCLUSION

Further case series and long-term follow up is required for accurate characterisation of phyllodes tumours with heterologous sarcomatous differentiation.

Malignant phyllodes tumor of the breast with predominant chondrosarcomatous differentiation

Malignant phyllodes tumor of the breast is a rare biphasic neoplasm, the stromal component of which may show homologous and heterologous sarcomatous elements. We present a case of a histologically malignant phyllodes tumor with sarcomatous overgrowth, affecting a 37-year-old woman in whom a chondrosarcomatous component constituted over 80% of the tumor volume. A malignant phyllodes tumor displaying a predominant chondrosarcomatous component is indeed rare, and the differential diagnosis could well affect the therapeutic approach, mainly with regard to metaplastic carcinoma and primary chondrosarcoma of the mammary gland. Thus, it is important to sample the tumor thoroughly to detect the presence of any area of typical phyllodes tumor, which could be very small. Immunohistochemical stains also should be performed so as to exclude a malignant epithelial component. After the final morphological diagnosis, our patient underwent a complete mastectomy without axillary disection. One year later, no local recurrence or metastasis was apparent.

Malignant phyllodes tumor of the breast: review of the literature and case report of stromal overgrowth

Cystosarcoma phyllodes constitutes only 0.3-0.9% of all breast tumors. The term "sarcoma" was initially used because of its fleshy appearance, a more modern term is Phyllodes tumor (PT). The behavior of PT constitutes a spectrum from benign and locally recurrent to malignant and metastatic. In a general surgical series, 6.2% of the tumors were malignant. The microscopic appearance of PT is that of epithelial elements and connective tissue stroma. Malignancy is determined by characteristics of the stroma. The metastatic spread of malignant PT is mainly hematogenous to lung, with infrequent lymphatic involvement. Wide local excision with 2 cm margins is the treatment of choice. In 20% of both benign and malignant cases, PT will locally recur. There is no proven benefit of radiation or chemotherapy, although radiotherapy may be useful in selected cases. We present a case of a sarcomatous overgrowth in a malignant phyllodes tumor involving multiple histologic types.