C80-06 Lobe and Behold: Recurrent Pneumonia Unveiling a Hidden Carcinoid

Abstract Introduction Pulmonary carcinoids are uncommon, comprising ∼2% of primary lung malignancy. They are often indolent, particularly when centrally situated. Even small endobronchial lesions can intermittently valve a lobar or segmental bronchus, leading to mucus stasis, atelectasis, and non-resolving pneumonia. CTs may show only lobar collapse or mucus impaction, and well-differentiated tumors are often minimally FDG-avid on PET-CT, delaying diagnosis. Adults with recurrent pneumonia warrant an anatomic search for obstruction. Bronchoscopy—even when CT/PET does not reveal a discrete intraluminal mass—permits direct visualization. Herein we present a case of an initially suspected parenchymal mass with possible metastasis to the hilar lymph node which in turn was revealed to be an endobronchial carcinoid leading to recurrent pneumonia. Case Report A 48-year-old Filipino female, non-smoker with past medical history of well-controlled asthma (on Albuterol and budesonide/formoterol) and endometriosis, initially presented to an outside emergency department with fever and flu-like symptoms. A CT chest revealed a left upper lobe (LUL) post-obstructive consolidation contiguous with a suspected left hilar mass (3.5 × 3.0 cm) and enlarged left hilar nodes, without effusion or pneumothorax. No discrete endobronchial mass was identified by CT at that time. The patient was recommended bronchoscopy and given antibiotics with transient improvement in her symptoms. She continued to report weight loss and progressively worsening dyspnea, denying any hemoptysis. As patient deferred biopsy a PET-CT was ordered revealing mild heterogeneous hypermetabolic activity in a large heterogeneous patchy infiltrate in the LUL (6.6 x 5 cm) with a SUV range of 2.2-4.7, with mildly hypermetabolic left hilar lymphadenopathy. Findings were non-specific but favored infectious/inflammatory etiology. She then underwent bronchoscopy which revealed a highly vascular obstructive endobronchial lesion at the entrance of the LUL bronchus (Image 1). Endobronchial biopsies confirmed a typical carcinoid. After one additional infectious flare treated with amoxicillin-clavulanate, she was referred to interventional pulmonology for possible snaring of the lesion. Since then, the patient has been lost to follow up. Discussion This case exposes a blind spot in imaging-first workups for recurrent pneumonia. Central carcinoids readily masquerade as mucus or lobar collapse on CT, and well-differentiated tumors often show low, heterogeneous FDG-uptake, producing nondiagnostic studies despite clinically meaningful obstruction. In non-resolving pneumonia in the same distribution especially without a compelling differential, bronchoscopy should move to the front of the diagnostic algorithm even if CT/PET fails to show a discrete intraluminal mass. Early airway inspection separates fixed tumors from secretions, secures tissue, relieves obstruction. This abstract is funded by: None