Primary Rhabdomyosarcoma of the Breast: Study of Three Cases at One Institution with a Review of Primary Breast Sarcomas

Management of Pediatric Breast Masses for the Pediatric Surgeon: Expert Consensus Recommendations From the APSA Cancer Committee

BACKGROUND

The pathology and management of breast masses in pediatric patients is markedly different than in adults. The vast majority of lesions in children and adolescents are benign, but the rare malignant breast masses require prompt recognition and treatment. Pediatric surgeons navigating clinical evaluation of these masses must balance preservation of the developing breast with appropriate diagnosis and surgical management.

METHODS

The current English language literature was queried for pediatric and adolescent breast masses. Identified manuscripts were reviewed and classified by level of evidence. Based on these results, as well as expert consensus, an algorithm regarding clinical workup and management was established.

RESULTS

Evaluation of pediatric breast masses begins with a thorough history and physical exam. Palpable masses should then be further characterized using an ultrasound-guided algorithm. In select cases, observation without surgical resection is appropriate. Surgical management of presumed benign lesions, when performed, should prioritize conserving developing breast tissue and the nipple areolar complex. Excisional biopsy is preferable to core needle biopsy when technically feasible. Surgical management of malignant lesions varies depending on the type of malignancy.

CONCLUSION

Pediatric surgeons are often the first point of contact after identification of a breast mass in a pediatric or adolescent patient, and therefore play a critical role in management. Based on literature review and expert consensus, we propose an algorithm to guide pediatric surgeons in the diagnosis and treatment of these predominantly benign lesions. For the rare malignant lesions, a multi-disciplinary team approach is recommended to optimize patient care.

LEVEL OF EVIDENCE: 5

Differential diagnosis of primary mesenchymal neoplasms of the breast

OBJECTIVE

While the majority of breast neoplasms originate from epithelial cells, a rare part of them originate from mesenchymal breast tissue. This study aims to present the histomorphological and clinicoradiological features of our series of primary mesenchymal breast tumors and to discuss the features of these tumors in light of the literature.

MATERIALS AND METHODS

Cases diagnosed as primary mesenchymal breast tumor in breast resection materials evaluated in our center between 2010 and 2023 were included.

RESULTS

Of the 26 tumors included, 57.7% were diagnosed as benign and 42.3% as malignant mesenchymal tumor. Cases diagnosed as benign mesenchymal tumor were hemangioma, lipoma, extra-abdominal fibromatosis, leiomyoma, angiofibroma, lipomatosis, benign fibrous histiocytoma and granular cell tumor. Histopathological study results were compatible with angiosarcoma in 5 (45.4%), undifferentiated sarcoma in 3 (27.3%), myxofibrosarcoma in 2 (18.2%) cases and rhabdomyosarcoma in 1 (9.1%) case.

CONCLUSION

Primary breast sarcomas are rarely seen compared to benign mesenchymal tumors and constitute less than 0.1% of all malignant breast tumors. When histomorphological findings suggestive of a mesenchymal tumor are observed in breast specimens, sufficient sampling should be performed to exclude a possible phyllodes tumor, and clinicoradiological findings should be examined to exclude the possibility of a metastasis.

Primary breast rhabdomyosarcoma in a 17-year-old girl

ABSTRACT

Primary rhabdomyosarcoma (RMS) of breast is a very rare malignancy usually affecting adolescent girls with a poor prognosis and no definitive treatment established. Here, we report a case of a 17-year-old girl who presented to us operated for a right breast mass with histopathology suggestive of RMS. She had undergone wide local excision with nipple-areola complex along with axillary node dissection for positive nodes. Immunohistochemistry was done which showed tumor cells which were positive for desmin and myogenin and were negative for leukocyte common antigen, cluster of differentiation 34 (CD-34), and AE1/AE3 which confirmed the diagnosis of RMS. She was planned for adjuvant chemotherapy but refused taking treatment. Two months later, she presented with local site recurrence for which re-excision was done, and she was started on adjuvant chemotherapy with vincristine, Adriamycin, and cyclophosphamide regimen after metastatic workup. She then received radiation treatment following which she is at present under follow-up with no signs of disease until now.

High-Grade Spindle Cell Lesions of the Breast: Key Pathologic and Clinical Updates

Most of the high-grade spindle cell lesions of the breast are malignant phyllodes tumors (MPTs), spindle cell carcinomas (SpCCs), and matrix-producing metaplastic breast carcinomas (MP-MBCs). MPTs have neoplastic spindle stromal cells and a classic leaf-like architecture with subepithelial stromal condensation. MPTs are often positive for CD34, CD117, and bcl-2 and are associated with MED12, TERT, and RARA mutations. SpCCs and MP-MBCs are high-grade metaplastic carcinomas, whereas neoplastic epithelial cells become spindled or show heterologous mesenchymal differentiation, respectively. The expression of epithelial markers must be evaluated to make a diagnosis. SAS, or rare metastatic spindle cell tumors, are seen in the breast, and clinical history is the best supporting evidence. Surgical resection is the standard of care.

Recurrent malignant phyllodes tumor of the breast: An extremely rare case of recurrence with only rhabdomyosarcoma components

Rhabdomyosarcoma is a rare disease that typically occurs in children. Rhabdomyosarcoma seldom occurs in the breast, and its diagnosis and treatment have infrequently been reported. The present case is a rare one of a recurrent malignant phyllodes tumor of the breast with only rhabdomyosarcoma components. A 69-year-old woman received a diagnosis of borderline phyllodes tumor of the left breast and underwent partial mastectomy. During follow-up, a left breast mass was found 1 year and 8 months after the previous surgery. Based on examination findings, it was suspected to be recurrent phyllodes tumor, so total left mastectomy was performed in our hospital. After the surgery, immunostaining failed to determine the epithelial component which may be produced by the proliferative part of stromal cells of previous phyllodes tumors. However, we could not exclude the possibility that this was a new tumor. After comparing samples with specimens from the first operation, it was finally determined to be a malignant phyllodes tumor with a rhabdomyosarcoma component. Therefore, chemotherapy was given, and vincristine, actinomycin D, and cyclophosphamide therapy was introduced. At the same time, radiation therapy was planned. Among phyllodes tumors, cases involving rhabdomyosarcoma components are very rare, especially those where the recurrence morphology only shows the same rhabdomyosarcoma components. This was a rare case with unique characteristics and great reference value.

Primary Small Cell Malignancies of the Breast: Are They Rare Malignancies?

In contrast with the other organs such as the lung, small cell tumors have been less studied in the breast due to their relatively less frequency. Although rare, neuroendocrine neoplasms, some lymphomas, and some small cell sarcomas such as undifferentiated small round cell sarcoma and rhabdomyosarcoma can be seen in small cell morphology in the breast. Many cytological specimens such as fine-needle aspiration biopsies and touch imprint cytology are used for diagnosis and further prognostic/predictive marker determination in primary breast masses, sentinel and axillary lymph nodes, and metastatic masses. Lobular carcinoma deserves to be considered in the small cell tumor group because of its small, monomorphic, discohesive, scant cytoplasmic cytological features. Since so many different types of tumors in the breast can have small cell characteristics, they should be divided into small cell neuroendocrine tumors and small cell nonneuroendocrine tumors. When evaluating small cell breast tumors cytologically, wide tumor diversity should be kept in mind, and clinical, hematological, and radiological features should be taken into consideration.

Primary rhabdomyosarcoma: An extremely rare and aggressive variant of male breast cancer

BACKGROUND

Rhabdomyosarcoma (RMS) of the breast, a mesenchymal neoplasm with skeletal muscle differentiation, is an extremely rare tumour in males, with less than 30 cases published in English-language literature. We report on the first case of a male breast RMS, with an unusual ectomesenchymal/neuroectodermal component.

CASE SUMMARY

A 55-year-old, previously healthy male, underwent a radical left mastectomy for an ulcerated tumour mass, occupying the breast and left anterior thoracic wall. The biopsy specimen indicated the presence of a tumour with neural origins, namely a peripheral neuroectodermal tumour (PNET). The surgical specimens identified two components. The rhabdomyosarcomatous component (over 70%) was represented by large pleomorphic cells with positivity for desmin, sarcomeric actin and myogenin. The PNET-like ectomesenchymal component, which was admixed with the RMS cells, and was also revealed during the preoperative biopsy, consisted of small cells which expressed neurofilament, neuron specific enolase and CD99. The microscopic examination, along with the immunohistochemical profile, allowed the diagnosis of an RMS, with unusual ectomesenchymal differentiation. The patient refused the postoperative oncologic therapy and died three months after surgery.

CONCLUSION

In patients with RMS of the breast, the PNET-like ectomesenchymal component increases the diagnosis difficulty, especially in biopsy specimens. This differentiation can be immunohistochemically proven and might highlight the possible development of high-grade sarcoma of the breast from remnants of the embryological ectodermal layer.