A Rare Case of Malignant Triton Tumor Without Associated Neurofibromatosis.

This paper describes a rare case of malignant triton tumor (MTT), a malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation, that occurred in a 21-year-old male with no concomitant clinical signs of neurofibromatosis. Although total surgical excision is ideal, the high recurrence rate and distant metastases frequently result in a poor prognosis. A biopsy, in this case, revealed spindle cells organized in short fascicles, with minor anisonucleosis and cross-striations indicating rhabdomyomatous differentiation. Positive immunohistochemistry for epithelial membrane antigen (EMA), Desmin, and S100 markers validated the diagnosis. For further treatment, the patient was referred to a cancer center. Even without clinical signs of neurofibromatosis type 1 (NF-1), the research emphasizes the need to evaluate MTTs as a differential diagnosis for individuals presenting with tumors in the head and neck area. Histopathology and immunohistochemistry are useful diagnostic techniques, and early intervention with surgical excision may enhance the outcome. The paper concludes with a review of the histological criteria needed to establish the diagnosis of MTT and the distinctions between sporadic and NF-1-associated tumors.

Rare case of stromal predominant Wilm's tumour with rhabdomyoblastic differentiation in FNAC smears.

The FNAC smear and histopathology of stromal predominant Wilm's tumour with rhabdomyoblastic Differentiation along with immunostaining in a 7-year-old male. In this paper, the diagnostic potential of FNAC in identifying rare histological variants of paediatric renal tumours is highlighted.

Laryngeal Sarcomatoid Carcinoma With Rhabdomyoblastic Differentiation: A Potential Pitfall for Misdiagnosis As Rhabdomyosarcoma.

Sarcomatoid carcinoma (SC) of the larynx is an uncommon subtype of squamous cell carcinoma which shows both squamous carcinoma and a sarcomatous component, including heterologous elements. The presence of rhabdomyosarcomatous elements in the larynx is extremely rare. Diagnosis of SC can be particularly challenging when the malignant epithelial component is not evident. We present a case of SC in a 72-year-old man with a superficial exophytic mass in the vocal cord initially misdiagnosed as rhabdomyosarcoma due to a predominant spindle cell component with rhabdomyoblastic features by morphology and immunohistochemistry. This case report aims to increase awareness that a rhabdomyoblastic heterologous component can be present in SC of the larynx and to consider this diagnosis in a mucosal exophytic malignant spindle cell neoplasm, even in the absence of epithelial differentiation.

Unusual morphologic features of low-grade endometrial stromal sarcoma: A case report.

BACKGROUND: Endometrial stromal tumours are uncommon tumours of the uterus. They mainly occur in perimenopausal women. Tumours with typical clinicopathological features do not usually pose diagnostic problems. However, rare clinicopathological features can occur, and clinicians without significant experience may have difficulty diagnosing these tumours and managing these patients. METHODS: Herein, we report a case of endometrial stromal sarcoma that occurred in a 25-year-old woman. The pathological features, immunophenotype, treatment and prognosis were discussed. RESULTS: The tumour revealed morphological heterogeneity, and there were similar proliferative-type endometrial stromal cells, an extensive amount of mature adipose tissue, and prominent rhabdomyoblastic and smooth muscle cells. Histopathological and immunohistochemical studies confirmed low-grade endometrial stromal sarcoma with smooth muscle, adipocytic and rhabdomyoblastic differentiation (approximately 60% were differentiated tissues). The final treatment of the tumour was total abdominal hysterectomy with bilateral salpingo-oophorectomy. There was no evidence of recurrence for 109 months postoperatively. CONCLUSIONS: We found that low-grade endometrial stromal tumours with extensive adipocytic and prominent rhabdomyoblastic differentiation are misdiagnosed because they are infrequent. They must be differentiated from rhabdomyosarcoma with accurate identification of adipocytes, and long-term follow-up is needed.

Pelvic Radiation-Induced Sarcoma With Rhabdomyoblastic Differentiation Following Treatment of Cervical Cancer.

Radiation-induced sarcomas (RIS) are a rare long-term complication of radiation therapy, with a reported incidence of 2.5-5.5%. They usually develop several years following exposure to radiotherapy. The most common reported subtypes are undifferentiated pleomorphic sarcoma, angiosarcoma, and leiomyosarcoma. Breast cancer is the most common primary malignancy preceding RIS, followed by uterine cervical carcinoma. Only a few cases of RIS with rhabdomyoblastic differentiation have been reported in the literature, usually following the treatment of retinoblastoma. Herein, we report a rare case of RIS with rhabdomyoblastic differentiation in the pelvic region developing 12 years after cervical cancer radiation therapy.

Elbow flexion reconstruction after arm-sparing excision for high-grade triton sarcoma: a case report.

BACKGROUND: Soft tissue sarcomas affecting the root of an upper extremity raise the question of limb amputation depending on their location, size, and malignancy. Malignant triton tumors are a rare subtype of neurofibrosarcomas that have been poorly reported in the literature. We report the case of a challenging reconstruction of the upper extremity using a pedicled latissimus dorsal flap. CASE PRESENTATION: A 25-year-old Occidental man was referred to our sarcoma unit for the management of a large, high-grade malignant peripheral nerve sheath tumor with no regional or distant extension and very fast progression. He was treated first by concomitant neoadjuvant radiotherapy and chemotherapy. Carcinologic excision was performed "en bloc" including the skin, the tumor, and the flexor muscles of our patient's elbow. Coverage of the skin defect and elbow flexion restoration were achieved by using a homolateral pedicled musculocutaneous latissimus dorsi flap. Histological analysis showed an R0 resection. The reconstruction process recovered a complete bending of his elbow. He is still in remission at 26 months follow-up. CONCLUSIONS: A malignant triton tumor is a rare, aggressive, and high-grade sarcoma. It was successfully treated and this case report describes an effective treatment modality. Reconstructive surgery, allowing large, complete tumor removal, is indispensable after neoadjuvant chemotherapy and radiotherapy.

Rhabdomyoblastic differentiation in rosai dorfman disease of the orbit in a 12-year-old male.

Extranodal Rosai-Dorfman disease involving the orbit has been reported severally with extensive discourse on management strategies. However, rhabdomyoblastic differentiation coexisting with the disease is yet unreported. We present the clinical and histopathological features of a 12-year-old boy presenting with both. A 12-year-old boy was referred to our Ophthalmic Plastic Surgical Service with a 5-year history of bilateral, progressively enlarging eyelid, orbital masses causing proptosis, and severe cosmetic blemish. He had suffered vision loss to the right eye following trauma 2 years prior to the onset of the disease. Computed tomography of the orbits revealed preseptal and intraorbital components of well-defined multi-lobulated masses in both orbits. No significant nodal involvement was noted. He underwent excision biopsy of the tumor in both eyes performed 1 month apart. A histopathologic diagnosis of the Rosai-Dorfman disease with focal areas of rhabdomyoblastic differentiation was made. He was treated postoperatively with a course of oral steroids with close observation for the rhabdomyoblastic differentiation. Rosai-Dorfman disease is an uncommon disease and has been reported to coexist with other pathologies. We highlight focal myoblastic differentiation within the excised tissues which may not necessarily warrant a diagnosis of rhabdomyosarcoma. Long-term follow-up of this patient is required to establish the safety of observation.

Malignant triton tumor of the duodenum: report of a case.

We report a case of malignant triton tumor of the duodenum, which is extremely rare. A submucosal malignant tumor was detected in the duodenum of a 49-year-old woman. The tumor was completely resected by performing pancreaticoduodenectomy. Pathological examination revealed that the lesion was a malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation, i.e., a malignant triton tumor. Long-term survival has been achieved with no recurrence at 8.5 years after surgery.

Malignant Triton Tumor of the Kidney. New Location Not Previously Reported.

Malignant triton tumor (MTT) is a variant of the peripheral nerve sheath tumor. It is very uncommon but shows an aggressive course and limited survival. Half of the cases present symptoms related to neurofibromatosis type 1 disease. There is no standardized treatment, but multimodal approach is the best option. We present the case of a primary MTT located in the kidney, in a 43-year-old woman who received neoadjuvant chemotherapy as first-line treatment followed by surgical resection and adjuvant chemotherapy.

Rhabdomyoblastic Differentiation in Head and Neck Malignancies Other Than Rhabdomyosarcoma.

Rhabdomyosarcoma is a relatively common soft tissue sarcoma that frequently affects children and adolescents and may involve the head and neck. Rhabdomyosarcoma is defined by skeletal muscle differentiation which can be suggested by routine histology and confirmed by immunohistochemistry for the skeletal muscle-specific markers myogenin or myoD1. At the same time, it must be remembered that when it comes to head and neck malignancies, skeletal muscle differentiation is not limited to rhabdomyosarcoma. A lack of awareness of this phenomenon could lead to misdiagnosis and, subsequently, inappropriate therapeutic interventions. This review focuses on malignant neoplasms of the head and neck other than rhabdomyosarcoma that may exhibit rhabdomyoblastic differentiation, with an emphasis on strategies to resolve the diagnostic dilemmas these tumors may present. Axiomatically, no primary central nervous system tumors will be discussed.

Malignant triton tumour of the sinonasal tract: Case report and literature review.

INTRODUCTION: The objective is to report a rare tumour of the sinonasal tract and conduct a literature review. Malignant triton tumour is a subtype of malignant schwannoma with rhabdomyoblastic differentiation. It is a very rare tumour, with only 15 reported cases involving the sinonasal region. PRESENTATION OF CASE: Forty-seven years old female presented with a right-sided epistaxis, progressive right sided nasal obstruction and anosmia and a visible mass in the right nasal cavity. Imaging studies showed a mass extending from the piriform aperture to the nasopharynx in contact with the dura and the orbital content. The mass was biopsied and the result was consistent with malignant triton tumour. The patient refused the surgery at first so chemotherapy with MAID protocol was started. After the fourth course of chemotherapy the treatment was stopped due to patient intolerance and a thrombosis of the jugular vein. Patient then underwent surgery with frontal craniotomy and dural excision, endoscopic control was done at the end to insure a complete removal. The patient received Radiotherapy in the postoperative period (56 Greys). At 5 years of follow up the patient is doing fine with no signs of recurrence and normal ophthalmological findings. DISCUSSION: Sixteen cases, including our case, have been reported to date in the literature. The mean age at presentation is 61 years. None of cases were associated with neurofibromatosis type 1. Eight patients were reported to be alive 5 years post-treatment, and 2 patients were reported to have died of the disease. The prognosis for triton tumours in the sinonasal tract is better than that for triton tumours in other locations. CONCLUSION: Malignant triton tumour is a rare malignancy of the sinonasal tract. Otolaryngologists should be aware of this disease. The optimal treatment should include radical resection of the tumour.

Melanoma with rhabdomyosarcomatous differentiation: two further cases of a rare pathologic pitfall.

We describe 2 new cases of malignant melanoma with divergent rhabdomyoblastic differentiation occurring in adult patients. The patients were women aged 67 and 51 years with primary cutaneous and uterine cervical melanoma, respectively. Rhabdomyoblastic differentiation in melanoma is very rare in adult patients, and to our knowledge, only 7 such cases have been described in the world literature, of which only 4 have conclusive documentation of the presence of rhabdomyoblastic differentiation. We present the fifth and sixth cases of adult melanomas with conclusive divergent rhabdomyoblastic differentiation, including the first noncutaneous (cervical) case; we also review the literature and highlight the potential for underrecognition of this phenomenon.

A case of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation: malignant triton tumor.

Malignant peripheral nerve sheath tumors (MPNST) constitute a rare variety of soft tissue sarcomas thought to originate from Schwann cells or pluripotent cells of the neural crest. Malignant triton tumor (MTT), a very rare, highly aggressive soft tissue tumor, is a subgroup of MPNST and is comprised of malignant Schwann cells coexisting with malignant rhabdomyoblasts. We herein report the case of a 24-year-old man who presented a subcutaneous mass in his right thigh. The mass was removed surgically in its entirety and radiation therapy was applied locally to prevent tumor regrowth. Nonetheless, the patient died 10 months after surgery from metastases to the lung and brain. He presented neither cafe-au-lait spots nor cutaneous neurofibromas. The histopathology showed a transition from a neurofibroma to an MTT, making this the second report of an MTT arising from a neurofibroma without neurofibromatosis type 1, an autosomal dominant disorder with which 50-70% of tumors reported in previous studies were associated. A histopathological examination using immunostaining with desmin confirmed this diagnosis. MTT has a poorer prognosis than MPNST and should therefore be regarded as a distinct clinical entity.

Hepatocellular carcinoma arising in a testicular teratoma: a distinct and unrecognized secondary somatic malignancy.

We report an interesting case of testicular germ cell tumor with distinct seminomatous and teratomatous components. A rare development of secondary somatic malignancy in the form of hepatocellular carcinoma was observed. Immunohistochemically, hepatocellular cancer was positive for cytokeratin, hepatocyte paraffin-1 (HepPar-1), α-fetoprotein, glypican-3 (GPC-3), octamer-binding transcription factor 3/4 (Oct3/4), and Ki-67. In addition, adenocarcinoma and rhabdomyoblastic differentiation were also evident. Placental alkaline phosphatase (PLAP), Sal-like 4, and Oct3/4 were positive in seminoma. To the best of our knowledge, we have not found any such report of secondary development of hepatocellular carcinoma in a testicular teratoma. We believe that it is a rare, distinct phenomenon in germ cell tumors and deserves recognition.

Malignant neuroectodermal tumor with melanocytic and rhabdomyoblastic differentiation.

Malignant melanoma can metastasize widely and vary significantly in its histological appearance; it rarely presents as a deep-seated mass without an obvious primary site elsewhere. Malignant peripheral nerve sheath tumor (MPNST) is a high-grade sarcoma characterized by conventional and epithelioid subtypes. MPNST can demonstrate heterologous differentiation, usually in the form of osteosarcomatous, chondrosarcomatous, or rhabdomyosarcomatous differentiation. MPNST does not harbor true melanocytic differentiation, although epithelioid MPNST typically is diffusely S-100 protein positive and superficially can resemble malignant melanoma. An unusual intra-abdominal mass was recently encountered with features of both melanoma and conventional or epithelioid MPNST containing a fascicular spindle cell component, an epithelioid component with melanocytic differentiation, as well as a rhabdomyosarcomatous component. The terminology "malignant neuroectodermal tumor with melanocytic and rhabdomyoblastic differentiation" is proposed to describe this neoplasm, reflecting the unusual concomittant lines of differentiation as well as offering a possible rationale for nosologically challenging aspects of this neoplasm.