Synovial sarcoma with ossification and calcification with SS18 immunochemical expression and rearrangement by fluorescent in situ hybridization

Synovial sarcoma is a soft tissue tumor of uncertain origin. Generally, it is a monophasic spindle cell neoplasm that can have glandular-like structures. Ossification and presence of calcification is a rare phenomenon with only a few reported cases. We present the case of a young male with a synovial sarcoma of the right foot. Histology revealed prominent deposits of tumoral osteoid and coarse calcifications. The diagnosis was confirmed by the expression of SS18 by immunohistochemistry and the demonstration of the rearrangement of the SS18 gene by fluorescent in situ hybridization. We reviewed the literature for synovial sarcoma with prominent ossification or calcification, and to the best of our knowledge, this is the first case with expression of SS18 by immunohistochemistry. The main differential diagnoses are osteosarcoma (both primary of bone and extraosseous) and sclerosing epithelioid fibrosarcoma.

[National guidelines of diagnosis and treatment of the non-Hodgkin lymphoma]

Non-Hodgkin lymphoma comprises a heterogeneous group of haematological malignancies, classified according to their clinic, anatomic-pathological features and, lately, to their molecular biomarkers. Despite the therapeutic advances, nearly half of the patients will die because of this disease. The new diagnostic tools have been the cornerstone to design recent therapy targets, which must be included in the current treatment guidelines of this sort of neoplasms by means of clinical trials and evidence-based medicine. In the face of poor diagnoses devices in most of the Mexican hospitals, we recommend the present diagnose stratification, and treatment guidelines for non-Hodgkin lymphoma, based on evidence. They include the latest and most innovative therapeutic approaches, as well as specific recommendations for hospitals with limited framework and therapy resources.