Rhabdomyosarcoma of the skin resembling carcinosarcoma: report of a case and literature review

Case Report: A PD-L1-Positive Patient With Pleomorphic Rhabdomyosarcoma Achieving an Impressive Response to Immunotherapy

There is currently a lack of effective systemic treatment for patients with advanced pleomorphic rhabdomyosarcoma (PRMS). Although programmed death protein 1 (PD-1) inhibitors have shown efficacy in various solid tumors, their effects on PRMS have not been well established. Here, we present a case of a 12-year-old Chinese male adolescent with metastatic PRMS who benefited from the PD-1 inhibitor nivolumab. The patient initially underwent primary tumor resection but failed to respond to subsequent first-line chemotherapy and second-line pazopanib treatment. Pathological examination showed positive PD-L1 expression and tumor-infiltrating lymphocytes in the tumor tissue, and the patient was administered nivolumab as a posterior-line treatment. After attaining a clinically partial response (PR), surgical resection was performed, which was followed by adjuvant nivolumab. At the time of the submission of this manuscript, the patient achieved recurrence-free survival (RFS) lasting 45 months and counting. This is the first clinical evidence that a patient with refractory PRMS was controlled by anti-PD-1 antibody, with an RFS lasting more than 3 years. This case suggests that PD-L1 expression and T-cell infiltration could be used as potential biomarkers for PRMS immunotherapy.

Cutaneous metastases of embryonal rhabdomyosarcoma in a black African child: the role of dermoscopy in reducing time to and cost of diagnosis

Cutaneous metastases are an uncommon feature of solid organ malignancies. The cost of multiple investigations and prolonged processing time of biopsies may lead to diagnostic delays especially in resource limited practice settings. Dermoscopy can provide useful clues and has been found to be useful in the diagnosis of cutaneous metastases. Dermoscopic findings of skin lesions may limit unnecessary investigations and shorten time to diagnosis. There are limited data on dermoscopic features of embryonal rhabdomyosarcoma in the literature. We report dermoscopic features of cutaneous metastasis of embryonal rhabdomyosarcoma seen in a black African child.

Giant Pendulous Carcinosarcoma - Squamous Cell Carcinoma-Type - of the Leg - A Case Report and Review of the Literature

Cutaneous carcinosarcoma (CCS) is a rare non-melanoma skin cancer with a biphasic growth pattern. A tumour is composed of epithelial and mesenchymal cells that show clonality. In most cases, CCS develops in the head-and-neck region on the chronic sun-exposed skin of males. Here, we describe an 80-year-old female patient who developed a giant, pendulous CCS on the leg. A tumour was surgically removed. We found no evidence of metastatic spread.

Case of pleomorphic rhabdomyosarcoma arising on subcutaneous tissue in an adult patient: Review of the published works of 13 cases arising on cutaneous or subcutaneous tissue

Rhabdomyosarcoma (RMS) is a malignant mesenchymal tumor usually occurring in children, young adults, and predominantly arising in the head and neck or deep soft tissue of the extremities. Pleomorphic RMS (PRMS) arising on subcutaneous tissue in an adult patient's trunk is extremely rare. We present a case of primary PRMS occurring on the back of a 50-year-old man. The tumor was diagnosed by histological and immunohistochemical findings of the resected specimen. One month after the surgery, axillary lymph node metastases were found. Subsequently, the patient received three cycles of combined chemotherapy. The rest of those axillary lymph nodes were reduced in size and there was no local recurrence 6 months postoperatively. PRMS is a very rare but aggressive tumor. Thus, it is important to confirm the diagnosis and provide adequate treatments.

Orbital rhabdomyosarcoma with skin metastasis: a case report

Background

Rhabdomyosarcoma is a soft tissue neoplasm that usually arises in the headand neck region and genitourinary tract. Skin metastasis of rhabdomyosarcoma is extremely rare; of thirteen cases reported in the literature, most were children younger than 10 years and only three cases have been reported in adults.

Case presentation

A 20-year-old Moroccan man was admitted with a right orbital tumor. The tumor was excised and histopathology examination confirmed a diagnosis of rhabdomyosarcoma. The patient was treated with chemotherapy, but local recurrence occurred one year later. The patient underwent right orbital exenteration followed by chemotherapy and radiotherapy. After 6 months, the patient developed a cutaneous mass in the right lumbar region, which was resected. Immunohistochemical examination of the tumor showed this to be a cutaneous metastasis of rhabdomyosarcoma. The patient was treated by chemotherapy and there appeared to be no recurrence after 9 months of follow up.

Conclusions

Skin metastasis from rhabdomyosarcoma is extremely rare, particularly in adults. The purpose of presenting this case report is to raise awareness among clinicians— skin biopsy and immunohistochemistry are needed to distinguish this neoplasm from other cutaneous tumors so that appropriate treatment can be initiated.

Cutaneous Pleomorphic Rhabdomyosarcoma Occurring on Sun-Damaged Skin: A Case Report

Rhabdomyosarcoma (RMS) is a malignant soft tissue tumor with skeletal muscle differentiation that can rarely present as a primary cutaneous tumor. There are 3 main subtypes of RMS: embryonal, alveolar, and pleomorphic. Primary cutaneous pleomorphic RMS is extremely rare, there being only 9 reported cases in the literature, 2 of which are radiation induced. We present a case of primary pleomorphic RMS occurring on the sun-damaged skin of the face of an 89-year-old woman. The tumor was diagnosed by histology, immunohistochemistry, and electron microscopy. The patient was treated by surgery and adjuvant radiotherapy. The tumor recurred rapidly after surgical excision. She died 2 months after the diagnosis from complications of treatment, local symptoms of tumor, and concurrent illnesses. Primary cutaneous pleomorphic RMS is a rare tumor of adults and pursues an aggressive clinical course.

Postradiation cutaneous pleomorphic rhabdomyosarcoma with extracellular collagen deposits reminiscent of so-called amianthoid fibers

Rhabdomyosarcoma is a malignant mesenchymal neoplasm that rarely presents as primary skin tumor. So-called amianthoid fibers are hyalinized collagen mats that have been described in myofibroblastic tumors but not in rhabdomyosarcoma. A 65-year-old male developed a submandibular nodule 9 years after an oral squamous cell carcinoma, which had been treated with chemotherapy and radiotherapy. Histological examination of the nodule revealed a pleomorphic rhabdomyosarcoma with extracellular collagen deposits reminiscent of so-called amianthoid fibers. By immunohistochemistry, the tumor cells were positive for vimentin, desmin, smooth muscle actin (SMA), muscle-specific actin (MSA), CD10, CD56, CD99, β-catenin and D2-40. However, only 15-20% of the tumor cells were positive for myoglobin, MyoD1 and myf-4/myogenin. We describe first so-called amianthoid fibers harboring blood capillaries in a rhabdomyosarcoma, suggesting that they are rigid collagen structures that lead to tumor vascularization. The low expression for myogenic regulatory proteins and strong expression for other markers may be misleading and do not contribute to the diagnosis of rhabdomyosarcoma.

Primary cutaneous rhabdomyosarcoma: a clinicopathologic review of 11 cases

BACKGROUND

Rhabdomyosarcoma is a malignant mesenchymal tumor with skeletal muscle differentiation. Primary cutaneous rhabdomyosarcoma is rare. We report a series of 11 cases of primary cutaneous rhabdomyosarcoma.

METHODS

Cases diagnosed as rhabdomyosarcoma arising in the dermis/subcutis with no identified primary tumor elsewhere were retrospectively reviewed. Follow-up was obtained.

RESULTS

The tumors occurred in five children and six adults. The adult subset consisted of pleomorphic, epithelioid and not otherwise specified (NOS) subtypes while the pediatric subset showed alveolar and embryonal subtypes. All cases showed immunohistochemical staining consistent with the diagnosis of rhabdomyosarcoma. Three adult cases showed immunoreactivity for cytokeratins (one pleomorphic, one epithelioid and one NOS.

CONCLUSIONS

Primary cutaneous rhabdomyosarcoma shows a bimodal age distribution and male predominance, correlating with rhabdomyosarcoma in deep soft tissue. Follow-up, available on all patients, showed aggressive behavior in both children and adults. Primary cutaneous rhabdomyosarcoma should be considered in the differential diagnosis of tumors with abundant eosinophilic cytoplasm and those with "small round blue cell" morphology. Desmin, myogenin and MYOD1 are a trio of markers with high sensitivity and specificity for primary cutaneous rhabdomyosarcoma. Cytokeratin immunoreactivity in primary cutaneous rhabdomyosarcoma represents a potential diagnostic pitfall in the differential diagnosis with sarcomatoid carcinoma.