Pulmonary carcinoid presenting with cavitating lung infection and oligometastatic mediastinal disease

A 25-year-old man, with no prior history of lung disease or relevant occupational exposure, presented with a 2-week history of fever, purulent sputum, dyspnoea with mild weight loss and lassitude. Significant examination findings included pyrexia of 39°C, and right basal crackles with a pleural rub. Bloods showed an elevated C-reactive protein level of 254 mg/litre, an elevated white cell count of 12.9 x 109/litre (with a neutrophilia). His chest radiograph showed multiple air-fluid levels in opacified lung, suggestive of cavitating pathology in the right lower zone, and a small pleural effusion (Figure 1). He responded very well to a course of augmentin but in view of his young age with the unusual radiographic appearances, computed tomography was undertaken (Figure 2). This showed a 4.7 cm soft tissue mass with patchy calcification occluding the basal bronchus of the right lower lobe, resulting in atelectasis and marked distal airway dilatation with endoluminal air-fluid levels. Subcarinal and subaortic adenopathy were also seen. He was ronchoscoped and this revealed a vascular polypoid lesion occluding the posterior basal segment of the right lower lobe suspicious for a carcinoid. Biopsies confirmed this to show morphological and mmunophenotypic features of a typical carcinoid. Tumour cells showed no mitoses and no necrosis and were mildly nuclear polymorphic. They expressed chromogranin (Figure 3), CD56 and thyroid transcription factor-1 (TTF-1). The patient underwent lobectomy. Macroscopic appearance (Figure 4) revealed a 12 x 10 x 6 cm well-circumscribed endobronchial tumour abutting the visceral pleura along with distal cystic ronchiectatic change. Histology confirmed a typical carcinoid characterized by nests and trabeculae of cells with round nuclei, stippled chromatin and moderate amounts of amphophilic cytoplasm. The tumour elicited a fibrous pseudocapsule. The hilar nodes were reactive but metastatic carcinoid tumour completely replaced the subcarinal node. The patient was referred to an oncologist for consideration of postoperative chemotherapy in view of the nodal involvement.