Abscopal effect in a patient with solitary extramedullary plasmacytoma of the thyroid: case report

Abstract

Background: The abscopal effect is a systemic antitumor response that occurs distant to the irradiation site and is induced by local irradiation. We herein describe a case of solitary extramedullary plasmacytoma (SEP) of the thyroid in which bone metastases disappeared after thyroidectomy and cervical radiotherapy (RT).Case Description: A 68-year-old man with a right cervical swelling for approximately 10 years visited a hospital with left elbow pain that persisted for 5 months. He was referred to our hospital for more detailed examinations and treatment. An immobile mass of approximately 10 cm in diameter was palpable on the right side of the patient's neck. Computed tomography (CT) showed osteolytic changes in the left humerus and right scapula, and a tumor in the right lobe of the thyroid gland. The patient was diagnosed with widely invasive follicular carcinoma and multiple bone metastases and underwent total thyroidectomy.During surgery, tumor infiltration into the trachea was observed. Shaving between the tumor and trachea was performed. Based on the results of a pathological examination, the patient was diagnosed with primary extramedullary plasmacytoma of the thyroid. After surgery, external beam RT was performed on the neck, which also reduced the pain in the left elbow. Positron emission tomography (PET)-CT showed the decreased accumulation of fluorodeoxyglucose (FDG) in the left humerus and right scapula, and the amelioration of osteolytic changes on CT.Conclusions: SEP of the thyroid is rare, and to the best of our knowledge, this is the first case report in which the abscopal effect was observed after thyroidectomy and cervical RT.

The abscopal effect and its implications for radiotherapy-immunotherapy combinations

“…The report by Aoyama et al in this issue ( 1 ) is one of a long line of case reports of the abscopal effect, although in this instance the first time this has been reported in a solitary extramedullary plasmacytoma of the thyroid. First described by Mole in 1953 ( 2 ), the typical occurrence is in a patient with widespread disease where one site of involvement is irradiated, and clinical responses are observed at other sites also.…”

18F-FDG PET/CT in Solitary Extramedullary Plasmacytoma of the Penis

“…The tumors exhibit a male predilection, with a ratio of nearly 3:1, and almost 90% of cases arise in the head and neck, particularly in the upper aerodigestive tract. [1][2][3][4][5][6][7][8] Various other sites for the presentence of solitary extramedullary plasmacytomas have been documented, 9 including gastrointestinal tract, 10,11 breast, 6 lung, 12 liver, 13 anterior mediastinum, 14 and retroperitoneum. 15 It should be noted that solitary extramedullary plasmacytoma involving the penis, particularly the corpora cavernosa, is extremely rare.…”

“…15 It should be noted that solitary extramedullary plasmacytoma involving the penis, particularly the corpora cavernosa, is extremely rare. 16 The 18 F-FDG PET/CT has demonstrated its value in the diagnosis, 4 staging, 6,8,10,17 evaluating response to therapy, 4,6,8,10 monitoring recurrence, 11 and predicting prognosis 18 of solitary extramedullary plasmacytomas. In cases with penile mass and increased 18 F-FDG uptake, this instance suggested that the solitary extramedullary plasmacytoma should be considered in the differential diagnosis.…”

“…Solitary extramedullary plasmacytomas, characterized with the neoplastic proliferation of a single clone of plasma cells in tissues outside the bone, account for approximately 2% of plasma cell malignancies. The tumors exhibit a male predilection, with a ratio of nearly 3:1, and almost 90% of cases arise in the head and neck, particularly in the upper aerodigestive tract [1][2][3][4][5][6][7][8]. Various other sites for the presentence of solitary extramedullary plasmacytomas have been documented,9 including gastrointestinal tract,10,11 breast,6 lung, 12 liver,13 anterior mediastinum,14 and retroperitoneum 15.…”