Superior vena cava syndrome in a patient with locally advanced lung cancer with good response to definitive chemoradiation: a case report

BACKGROUND: The incidence of superior vena cava syndrome within the United States is roughly 15,000 cases per year. Superior vena cava syndrome is a potentially life-threatening medical condition; however, superior vena cava syndrome is not fatal in the majority of cases. Superior vena cava syndrome encompasses a collection of signs and symptoms resulting from obstruction of the superior vena cava, including swelling of the upper body of the head, neck, arms, and/or breast. It is also associated with cyanosis, plethora, and distended subcutaneous vessels. Lung cancer, including both non-small cell lung cancer and small cell lung cancer, is the most common extrinsic cause of superior vena cava syndrome. Intrinsic disruption of superior vena cava flow can also precipitate superior vena cava syndrome. This case report describes an unusual presentation and potential etiology of superior vena cava syndrome. CASE PRESENTATION: Our patient was a 51-year-old black woman with locally advanced, stage IIIB non-small cell lung cancer who had no clinical symptoms of superior vena cava syndrome at the time of diagnosis. However, she did have radiographic evidence of superior vena cava stenosis caused by extrinsic compression from her large right hilar primary tumor. She was treated with definitive chemoradiation, receiving 60 Gy of external beam radiation therapy given concurrently with chemotherapy. Three months after completion of radiotherapy, she developed signs of superior vena cava syndrome, including breast and supraclavicular swelling. She had a chest computed tomography scan showing over 50% reduction in the size of a right hilar mass; however, she had continued radiographic stenosis of the superior vena cava. The distribution of stenosis appeared to be inferior to the caudal extent of pretreatment tumor volume. She had no other radiographic indications for superior vena cava syndrome. CONCLUSIONS: Generally, superior vena cava syndrome is the result of extrinsic compression of the superior vena cava by tumor. Our patient’s case represents the development of superior vena cava syndrome after an excellent response of tumor with near-complete tumor response. We suspect chemoradiation therapy as a potential etiology for the precipitation of the superior vena cava syndrome, which is currently not well reported in the medical literature.