[Progressive myositis ossificans: Case report].

Background: Myositis ossificans progressiva (MOP) is a low prevalence hereditary connective tissue disease (1:2,000,000 habitants). It is characterized by heterotopic ossification with an uncertain behavior that has been exceptionally related to neoplasms. The objective was to know the coexistence of MOP with neoplasms of mesodermal origin, so that they can be considered in the diagnosis of other patients, as well as formulate hypotheses to clarify their association. Clinical case: 27-year-old female with right gluteal and ischitiobial muscle pain that increased with exercise, without remission with analgesics until limiting the mobility of both extremities. A bone series was requested where areas of heterogeneous radiolucency were evidenced in the region of, both, thighs and pelvis in an irregular manner, similar to bone density, which was compatible with the ultrasound and tomographic findings; we concluded that they were images of myositis ossificans of the hip. The patient reported gastric symptoms and an endoscopy was requested, which histopathologically reported diffuse gastric carcinoma with signet ring cells; cabinet images showed an ovarian tumor. Conclusion: MOP is a low prevalence disease, which is why its knowledge and suspicion are essential for the diagnosis. We found little literature that involves the three entities; therefore, their pathophysiology and understanding is limited. Regarding MOP, at this moment there is no curative treatment; however, an accurate diagnosis allows to start rehabilitation in a timely manner with an improvement in the quality of life.