INTRODUCTION: Kaposi Sarcoma (KS) occurs in the classic, endemic, iatrogenic (in patients on immunosupression) and acquired immunodeficiency syndrome (AIDS) related forms. KS in immunocompetent host rarely involves the visceral organs. Kaposi's sarcoma-associated herpes virus (KSHV) is involved in the oncogenesis of KS and is found in KS lesion tissue.
CASE PRESENTATION: A 40-year-old black man with mild asthma presented with worsening shortness of breath. He had noted fever, productive cough and about 30 lb weight loss. He was born and lived in New York City. He was heterosexual, monogamous and had no history of intravenous drug use. He had bilateral chest dullness; skin and rest of the exam were normal. Initial radiology showed bilateral large pleural effusions, right greater than left; right pneumothorax, multiple pulmonary masses, some with cavitation and large cystic lesions in the pulmonary parenchyma. He also had large pericardial effusion. Bilateral chest tubes were placed and revealed exudative pleural effusions, negative for malignancy. Fiberoptic bronchoscopy showed no endobronchial lesions and silver stain was negative for Pneumocystis. Patient underwent video assisted thoracoscopic surgery, pericardial drainage with catheter placement and biopsy of the lung masses. Pathology revealed multifocal angioproliferative lesions consisting of slit like vascular spaces surrounded by spindle cells, consistent with KS. The immunohistochemical stain was positive for CD31 and D2-40; KSHV staining was negative. Patient tested negative for HIV (repeated weeks later) and his CD4 count was over 1200 cells/μl, serology for KSHV was negative. He was started on chemotherapy with weekly paclitaxel. Patient tolerated the chemotherapy well; improved clinically, his respiratory complaints resolved and he reported weight gain. CT chest 6 month after starting paclitaxel showed near complete resolution of pulmonary masses and cavitary lesions, no pleural effusions and some loculated pericardial effusion.
DISCUSSIONS: KS is an angio-proliferative disorder consisting of slit like vascular channels and spindle cells surrounded by inflammatory cells. In patients not on anti-retroviral therapy (HAART) KS usually involves the lungs, has high tumor burden and is rapidly progressive. Visceral involvement is rare in an immunocompetent host. There has been previous case report with KS with lung involvement in immunocompetent host, with very poor outcome despite chemotherapy (1). Recently KS has been reported in patients without AIDS but in men having sex with men, but KS in those cases almost always involved the skin, were KSHV positive and has a rather indolent course (2). In this report 12% of the patients serology negative for KSHV (2). This is a rare case of KS in a patient without AIDS and negative for KSHV. KSHV serology and staining was negative in our case, likely due to difference in biology of this case from AIDS related KS or less likely false negative test. Treatment of KS in AIDS related KS is institution of HAART, and chemotherapy is indicated in life-threatening visceral disease. Liposomal doxorubicin and paclitaxel are the commonly used chemotherapeutic agents. Paclitaxel was chosen in this case due to its efficacy and favorable side effect profile. In addition to its anti-neoplastic effects palcitaxel is thought to have anti-angiogenic activity, which could contribute to its effectiveness in this tumor type.
CONCLUSION: KS may affect young adults without AIDS or exposure to immunosuppression. Treatment with paclitaxel is very effective for such extensive pulmonary KS involvement.
DISCLOSURE: Arvind Ponnambalam, No Financial Disclosure Information; No Product/Research Disclosure Information