Electrocautery Snare Resection and Argon Plasma Coagulation of Endobronchial Kaposi Sarcoma Presenting as an Obstructing Tumor.

SESSION TITLE: Bronchology/Interventional Global Case ReportsSESSION TYPE: Global Case ReportPRESENTED ON: Tuesday, October 28, 2014 at 01:30 PM - 02:30 PMINTRODUCTION: Kaposi sarcoma (KS) remains the most common AIDS-associated neoplasm. Endobronchial KS typically appears as slightly raised, violaceous lesions in the sub-mucosa of the endobronchial wall and is usually associated with similar mucocutaneous lesions elsewhere on the body. We herein describe an unusual case of KS presenting as an isolated obstructing endobronchial tumor that was effectively resected using electrocautery snare and argon plasma coagulation (APC).

CASE PRESENTATION: A 40 year-old Caucasian male never-smoker with four weeks of progressive cough, wheezing and dyspnea was referred for evaluation of an endobronchial tumor. His past medical history was significant for previously undisclosed and untreated HIV. Physical examination demonstrated no abnormal findings of the skin or oral mucosa. A CT scan of the thorax revealed a polypoid endobronchial tumor in the distal right mainstem bronchus and right paratracheal lymphadenopathy, but no evidence of parenchymal disease. Inspection bronchoscopy revealed a near complete obstructing mass in the distal right mainstem bronchus anchored on a wide stalk with otherwise normal-appearing bronchial mucosa throughout the remainder of the tracheobronchial tree. Fine needle aspiration, followed by electrocautery snare (ConMed, Utica, NY), was used to sample and resect the mass, respectively. Bleeding was well-controlled using argon plasma coagulation (APC). Pathologic examination was positive for human herpesvirus 8, confirming the diagnosis of Kaposi sarcoma. His absolute CD4 count was 78 per microliter. The patient returned three days later with fever and progressive shortness of breath. Thoracic imaging revealed interval development of multifocal, bilateral pulmonary ground glass opacities. Inspection bronchoscopy demonstrated partial obstruction of the BI lumen with devitalized tissue. Balloon dilation using an 8-9-10 pulmonary CRE balloon (Boston Scientific, Natick, MA) improved the airway patency. BAL fluid from the lingula tested positive for parainfluenza virus. Repeat therapeutic bronchoscopy two days later for definitive debulking of devitalized tissue revealed a 5 mm defect in the lateral wall of the distal BI, likely from previous electrocautery. Cryo-recanalization using a 2.4 mm Cryoprobe (Erbe, Germany) resulted in significant improvement in lumen size. Follow-up inspection bronchoscopy eight weeks later, after initiation of antiretroviral therapy, revealed minimal airway abnormality, maintained airway patency and well-healing bronchial tear.DISCUSSION: Endobronchial lesions associated with both endemic and immunosuppression-related Kaposi sarcoma (KS) are commonplace. The vast majority appear as flat-to-slightly-raised violaceous lesions, often near minor carinae. Simultaneous skin and oral mucosal KS lesions are the norm, but endobronchial findings in the absence of lesions elsewhere on the body are not uncommon. However, endobronchial KS presenting as an obstructing mass without concurrent mucocutaneous disease has been reported previously only twice. Aside from the unusual presentation, our case is unique in that the airway mass was intervened upon using bronchoscopic techniques not previously described for KS. Its polypoid nature made it amenable to snare electrocautery resection and its wide pedicle, suggesting endobronchial invasion, necessitated coagulation to minimize bleeding and to destroy residual malignant tissue. We chose APC because of its ease, its improved safety profile and its equivalency in re-establishing airway patency over Nd:YAG laser. Bleeding risk was minimized with snare electrocautery given simultaneous cauterization of the base of the tumor during resection. The risk of iatrogenic endoluminal damage is similar with either laser and electrocautery.CONCLUSIONS: Kaposi sarcoma presenting as a localized, obstructing airway mass without concurrent mucocutaneous disease is extremely rare, but should be considered in the differential diagnosis in patients with known immunocompromised state. While the risk of complication during manipulation remains, advanced endoscopic techniques provide practitioners with additional methods for diagnosis and for response should complications occur. Reference #1: Nathan S, Vaghaiwalla R and Mohsenifar, Z. Use of Nd:YAG Laser in Endobronchial Kaposi's Sarcoma. Chest 1990; 98:1299-1300.Reference #2: Chin R Jr, Jone DF and Pegram PS. Complete Endobronchial Occlusion by Kaposi's Sarcoma in the Absence of Cutaneous Involvement. Chest 1994; 105:1581-82.DISCLOSURE: The following authors have nothing to disclose: Alfred Papali, Ashutosh Sachdeva, Edward Pickering, Nirav ShahNo Product/Research Disclosure Information.