Occult Pulmonary Adenosquamous Carcinoma Presenting With Synchronous Colonic Metastases.
Mary Hunter Hyche, Isabella Lopez, Christine Marie-Gilligan Schammel et al.
✦ AI-curated · Sources linked
Case in brief
A 60-year-old woman with a substantial smoking history and COPD presented with a refractory exacerbation, without a discrete lung parenchymal mass. CT angiography instead showed left upper-lobe bronchial wall thickening, and bronchoscopy found high-grade endobronchial stenosis. Mediastinal sampling showed non-small cell lung carcinoma; staging revealed colonic metastases with an immunophenotype supporting pulmonary adenocarcinoma. Adrenal resection later demonstrated squamous differentiation, establishing pulmonary adenosquamous carcinoma. She received histology-guided multimodal and salvage treatment, including palliative adrenalectomy for pain, and survived 42 months from diagnosis.
What made this case unusual
The primary lung cancer lacked a discrete parenchymal mass and first came to attention with synchronous colonic metastases. Different metastatic samples showed divergent glandular and squamous differentiation, complicating classification as adenosquamous carcinoma.
Diagnostic / clinical pearl
When metastatic lesions show differing morphologies or immunophenotypes, adequate sampling across sites can reveal divergent differentiation and clarify the primary tumour’s classification.