Laryngeal kaposi's sarcoma in a renal-transplant recipient.

Abstract

Kaposi’s sarcoma (KS) was first described in 1872, and four variants, including classic, endemic, immunosuppression-associated, and epidemic (or AIDS)-associated KS have been described (1). They have identical histologic features but develop in different patient populations and variable organs. KS rarely involves the larynx; all patients reported with laryngeal involvement had classic or AIDS-associated KS (2–5). Here, we present a renal recipient with a solitary laryngeal KS successfully treated with primary tumor excision and reduction of immunosuppressants. A 49-year-old Taiwanese woman with negative AIDS serology received a living-nonrelated renal transplantation in February 2001. The initial posttransplant immunosuppressants were cyclosporine (CsA) and steroids. Pulse therapy with 2 g of methylprednisolone and mycophenolate mofetil were given 2 weeks after the transplantation because of an acute rejection episode (Banff grade I). She had two episodes of upper gastrointestinal bleeding in May 2001 when a panendoscopy showed erosive gastritis and a duodenal ulcer. Pneumocystis carinii pneumonia and oral herpes simplex infection occurred in June 2001. CsA was changed to tacrolimus in August 2001 because of unstable serum creatinine levels and fluctuations of CsA concentrations. She had a sore throat with dry cough in May 2002. Her immunosuppressants were 12 mg of tacrolimus (trough level 7.2 ng/mL) and 7.5 mg of prednisolone per day at that time. Indirect laryngoscopy showed a purplish granular tumor about 2 cm in diameter over the supraepiglottis (Fig. 1A). A neck magnetic resonance image showed a lobulated mass with heterogenous enhancement at the larynx. Primary tumor excision was performed by way of direct videolaryngoscopy. Microscopically, this excision showed proliferative spindle cells arranged in a stream pattern with intermingled vascular slits (Fig. 1B), indicating a laryngeal KS. Polymerase chain reaction confirmed the existence of human herpes virus 8 in the specimen. Figure 1: (A) Indirect laryngoscopy showed a purplish granular tumor about 2 cm in diameter over the supraepiglottis. (B) Proliferative spindle cells arranged in a stream pattern with intermingled vascular slits. KS, Kaposi’s sarcoma; E, epiglottis; T, tongue base; P, posterior pharyngeal wall.Immunosuppressants were reduced to 6 mg of tacrolimus (trough level 4.4 ng/mL) and 5 mg of prednisolone per day under the diagnosis of immunosuppression-associated KS. There is no evidence of recurrence or metastasis of KS, and her renal function is stable thus far. Transplant-associated KS typically involves lymph nodes, mucosa, and visceral organs, sometimes in the absence of skin lesions (1). This is the first report of a laryngeal KS in a renal allograft recipient. Most classic and AIDS-associated laryngeal KS are associated with typical skin lesions or simultaneous visceral involvements (2–3). In contrast with previously reported laryngeal KS, this patient had only one solitary laryngeal lesion without skin or visceral involvements. Patients with localized KS are usually treated with local treatment modalities whereas systemic therapy is reserved for generalized KS (1). Radiotherapy (2,3) and intralesional chemotherapy (4) had been used successfully in treating laryngeal KS. Single, pedunculated and superficial lesions can be treated with endoscopic excision (5). In this patient, the tumor was located at the free margin of the epiglottis and the aryepiglottic fold and was excised without sequela. KS in transplant recipients causes less mortality, mainly because the immunosuppression can be reduced or totally stopped. However, this might lead to approximately 50% graft loss in renal recipients (1). In this patient, after the tumor excision and reduction of immunosuppressants, she had stable graft function in the following 10 months. Chun-Hou Liao1 Jeng-Yuh Ko1 Shih-Chieh J. Chueh1 Ming-Kuen Lai1 Jun Chun1 Jenq-Yuh Ko2