Successful use of three-dimensional conformal radiotherapy as adjuvant treatment for alveolar soft part sarcoma. A case report

Alveolar soft part sarcoma is a very rare and aggressive type of sarcoma. Although its histology and genetic characteristics have been identified, the benefits of adjuvant radiotherapy for its treatment are still being studied.Case presentation: In November 2007, a 21-year-old woman presented with a primary tumor in the right thigh, with histological and immunohistochemical confirmation of an alveolar soft part sarcoma, which was totally resected in December 2007. Also, the large size of the mass suggested an unfavorable evolution. Two years after the first surgery, two metastatic tumors were detected in the right lung, which were completely resected separately. Two years later, the patient had two independent relapse events, five months apart: a mass in the right tight, and a metastatic tumor in the adrenal gland together with relapse in the tight. All tumors were successfully resected. In June 2014, after the last local relapse, adjuvant radiotherapy was started because of the risk of thigh amputation. At the end of treatment, the patient’s general condition was good. Currently, at age 34, the patient is monitored through periodic evaluations, showing disease regression and stabilization.Conclusions: Currently, it is known that radiation not only produces cytotoxic effects on the target region, but also induces an immune system-mediated systemic response with potential antimetastatic properties. The emerging radiobiological paradigms should be considered, particularly since they could explain some encouraging and unexpected results such as those described in this case.