Spindle Cell Sarcoma

Complete surgical resection remains the treatment of choice and typically results in rapid metabolic resolution. As the role of adjuvant therapy is not yet well established, accurate histopathological evaluation, appropriate risk stratification, and long-term surveillance are crucial to optimize outcomes and detect recurrence early.

Primary breast leiomyosarcoma is a rare entity that remains diagnostically challenging. Immunohistochemistry is essential for accurate diagnosis, and optimal management requires a dedicated multidisciplinary approach.

Accurate diagnosis requires histopathological evaluation with EBV confirmation. Management remains challenging and often centers on local tumor control and immune reconstitution.

This case illustrates the compounding diagnostic pitfalls of oral IMT: dual-site involvement, two failed biopsies, ALK negativity in an elderly patient, and focal cytokeratin positivity risking misclassification as spindle cell carcinoma. Awareness of IMT histologic subtypes, meticulous tissue sampling, and systematic immunohistochemical profiling are essential to avoid misdiagnosis and unnecessary aggressive oncologic treatment.

No disease progression was observed at 9 months. This case demonstrates the potential efficacy of combination immunotherapy in aggressive metastatic MTSCC.

Continuous genomic monitoring is essential for identifying resistance mechanisms and guiding precision therapy. Future studies should explore the impact of different fusion partners on tumor behavior and therapeutic response.

Immunohistochemistry confirmed positivity for smooth muscle actin and vimentin with a Ki-67 index of 15%-20%, consistent with myopericytoma. The short-interval recurrence, invasive features, and high mitotic activity raised concern for malignant myopericytoma.ConclusionThis being only the second reported breast myopericytoma case report, highlights the diagnostic difficulty and emphasizes the importance of thorough pathologic and immunophenotypic assessment to distinguish it from more common spindle cell tumours of the breast and to guide appropriate surgical management.

RAF/BRAF-driven mesenchymal tumours possess a broader clinicopathologic spectrum than traditionally recognised, frequently affecting adults and deep/visceral sites. Their inherently variable immunophenotypes and the presence of high-grade morphologic features do not strictly predict an aggressive clinical trajectory. Comprehensive molecular profiling is essential to refine diagnostic criteria, accurately identify these neoplasms, and elucidate the genomic events associated with tumour progression.

P2, N=798, Active, not recruiting, National Cancer Institute (NCI) | Trial primary completion date: May 2027 --> May 2026

Adult-onset ALK-positive IMT with extensive pulmonary involvement and multiorgan metastases is exceedingly rare. This case highlights the diagnostic challenges posed by sarcomatoid morphology and underscores the importance of integrating histopathology, immunohistochemistry, and clinical correlation, with ALK testing providing both diagnostic confirmation and a potential therapeutic target.

On follow-up PET-CT scan after imatinib therapy, the patient showed a complete/near complete metabolic response. This report expands the imaging spectrum of PHGIST and emphasizes the importance of radiologic-pathologic correlation in distinguishing this rare lesion from metastatic liver disease.