Postradiation sarcoma of the chest wall: report of two cases

Liposarcoma of the pleural cavity

Liposarcoma rarely occurs in the pleura or thoracic cavity, and few reports appear in the literature. We hypothesized that combining clinicopathologic, immunohistochemical, and fluorescence in situ hybridization methods would allow definite diagnoses. Using formalin-fixed, paraffin-embedded blocks, we examined 6 atypical lipomatous tumor/well-differentiated types (ALT/WDLPS), 5 dedifferentiated types (DDLPS), 2 pleomorphic types, and 1 myxoid type (MLSP). We used the Kaplan-Meier method and the Wilcoxon test for survival analysis for prognostic factor evaluation. Histologically, ALT/WDLPS was composed of a relatively mature adipocytic proliferation, accompanied by some lipoblasts. DDLPS exhibited round-to-oval tumor cells with a high nucleus-to-cytoplasm ratio that had proliferated in nests, accompanied in case 10 by some giant cells but no fatty cells. The pleomorphic type contained a varying proportion of pleomorphic lipoblasts. MLSP displayed uniform round to oval-shaped cells and small signet-ring lipoblasts in a myxoid stroma. Immunohistochemically, 11 (79%), 11 (79%), and 10 (71%) of 14 cases were positive for S-100, p16, and CDK4, respectively. Six (43%) of the 14 cases were positive for MDM2, and adipophilin. One case of ALT/WDLPS and 3 cases of DDLPS exhibited MDM2 amplification by fluorescence in situ hybridization (Vysis LSI MDM2 SpectrumGreen Probe plus Vysis CEP 12 SpectrumOrange probe). ALN/WDLPS was the most favorable type for survival, while adipophilin tended to be a negative prognostic factor for pleural liposarcoma. For a firm diagnosis of liposarcoma in the pleura, immunohistochemistry for CDK4, MDM2, and adipophilin together with MDM2 gene amplification by fluorescence in situ hybridization may be an important diagnostic tool.

Unusual Presentation of Postradiation Sarcoma With Subsequent Intestinal Metastasis Revealed by 18F-FDG PET/CT

Radiation-related sarcoma is a rare but serious complication for patients after receiving radiation therapy initially for their primary malignancy. However, it usually takes several years and needs enough in-field radiation dose to develop this sarcoma. We describe a 60-year-old man with right axillary sarcoma revealed by whole-body F-FDG PET/CT 1 year after chemoradiotherapy, which presented ultrashort latency period and did not match the consensus definition of radiation-related sarcoma. Besides, metastatic sarcoma to small intestine was accidentally noted in the F-FDG PET/CT image.

Surgical Management of the Radiated Chest Wall and Its Complications

Radiation to the chest wall is common before resection of tumors. Osteoradionecrosis can occur after radiation treatment. Radical resection and reconstruction can be lifesaving. Soft tissue coverage using myocutaneous or omental flaps is determined by the quality of soft tissue available and the status of the vascular pedicle supplying available myocutaneous flaps. Radiation-induced sarcomas of the chest wall occur most commonly after radiation therapy for breast cancer. Although angiosarcomas are the most common radiation-induced sarcomas, osteosarcoma, myosarcomas, rhabdomyosarcoma, and undifferentiated sarcomas also occur. The most effective treatment is surgical resection. Inoperable tumors are treated with chemotherapy, with low response rates.

Multidisciplinary approach to treatment of radiation-induced chest wall sarcoma

Radiation-induced sarcoma (RIS) is a rare complication following therapeutic external irradiation for lung cancer patients. Patients with RIS may develop recurrence or metastasis of the previous disease and also at high risk for early chest wall complications following operation, which requires close follow-up and multidisciplinary approach. We present a challenging case of RIS with a multidisciplinary teamwork in the decision-making and successful management.