Primary mediastinal seminoma; resistance and relapse: An aggressive entity
A 22-year-old male presented with a history of progressive dyspnea, cough, hoarseness of voice, and unquantified weight loss for the last 6 months in Feb 2010. On clinical examination, there were signs of superior vena cava syndrome, with 5 cm × 6 cm left supraclavicular mass. The whole body computed tomography (CT) scan showed heterogeneously enhancing 12 cm × 8.2 cm × 4.2 cm firms soft-tissue mass in the mediastinum encasing ascending aorta, arch of aorta, right main pulmonary artery, and proximal bronchi, infiltrating superior vena cava []. The ultrasound of scrotum was unremarkable. The biopsy of left supraclavicular mass was consistent for extragonadal seminoma with imunohistochemistry positive for C-kit and negative for leucocyte common antigen, epithelial membrane antigen and PLAP. The serum lactate dehydrogenase (LDH) was raised to 1963 U/L (normal range 100-190 U/L) while β- human chorionic gonadotropin (β- HCG < 1.20 mlU/ml) and alpha fetoprotein AFP (2.73 ng/ml) were normal. The baseline complete blood counts, renal and liver function tests were found to be normal.\nThe patient received chemotherapy comprising of bleomycin, etoposide, and cisplatin (BEP; Bleomycin 18 U/m2 IV, Etoposide 100 mg/m2, Cisplatin 20 mg/m2) 3 weekly for four cycles until July 2010. The patient tolerated chemotherapy well with no dose reductions. There was a serial reduction in serum LDH values. The response assessment CT showed residual disease of 5.8 cm × 4 × 4 cm and elevated serum LDH of 221 U/L. To consolidate the partial response and vascular involvement precluding surgery; external beam radiation to a dose of 30 Gy in 17 fractions over 3 weeks was given to the mediastinum and supraclavicular region. The 6 MV photons with the tomotherapy (high precision arc intensity modulated radiation with image guidance) were used to irradiate the planning target volume, which included clinical target volume (CTV) with a margin of 5 mm for set-up error. The CTV included gross residual tumor as seen on planning CT with 5 mm margin. The post-radiation positron emission tomography-CT (PET-CT) showed complete metabolic regression of the disease and the normal serum LDH. Patient was on regular follow-up with tumor markers and CT thorax abdomen pelvis every 3 monthly.\nAt 1 year patient presented with rapidly progressing right side cheek swelling (5 cm × 6 cm) and progressive lower backache. On examination, there was local tenderness in cheek swelling and in the region of 5th lumbar vertebrae. The CT showed a soft-tissue mass involving subcutaneous plane of right cheek of 6 cm × 6 cm × 4 cm []; increased size of mediastinal mass (10 cm × 8 cm × 6 cm) and multiple lytic lesions in ribs. The fine needle aspiration cytology from check swelling showed cells consistent with the metastatic seminoma collaborated with raised serum LDH values (353U/L). The serum β-HCG and AFP were normal. The technetium-99 m- methylene diphosphonate MDP bone scintigraphy revealed multiple metastases in ribs and 5th lumbar vertebra.\nAfter discussion in institutional joint tumor board meeting keeping the view of disease status, poor performance status and patient wishes; he was offered short course palliative radiotherapy to right face and lumbar spine with the supportive care. Review after 4 weeks showed poor pain relief and progressive disease. Taking an overall view of patient performance status advanced disease, distant geographical location, challenged socio-economic status and discussions with the patient and family members; further anti-neoplastic therapy was precluded and best supportive care was offered. Patient succumbed to progression of the disease shortly.