Short-term spontaneous regression of myxofibrosarcoma in the scapular region.

Spontaneous regression of cancer is a well-known but rare phenomenon, and it is extremely rare for sarcomas. The current case is an 85-year-old woman with a multinodular lesion diagnosed as myxofibrosarcoma in the scapular region. The maximum size of the tumor at the initial visit was 10 cm, and it decreased to less than 2 cm without any treatment. After a period of regression of about 6 months, the tumor began to grow, and resection was performed. No prior case of spontaneous regression has been reported in myxofibrosarcoma or other primary sarcomas. Interestingly, the regression took place after the occurrence of pneumonia, suggesting a possible relationship.