Resection of a colloid adenocarcinoma of the lung: A case report

Colloid adenocarcinoma of the lung is a rare subtype of lung adenocarcinoma, accounting for only about 0.24% of lung cancers. Because of its rarity, long-term postoperative prognostic reports are limited. In this report, we describe a case of colloid adenocarcinoma of the lung with a 5-year recurrence-free follow-up. The patient is a 66-year-old woman. During postoperative follow-up for ovarian cancer, chest CT showed a 45 x 30 mm sized mass in the left lung with mixed low-absorption areas inside that were suspicious of cystic lesion. We suspected metastatic lung tumour, and performed lower lobectomy. Pathological examination revealed pale tumour cells forming a glandular lumen with internal mucus production. Based on the results of immunostaining we diagnosed colloid adenocarcinoma of the lung. She received postoperative adjuvant chemotherapy and is alive 4 years postoperatively without recurrence. Colloid adenocarcinoma of the lung, even if large, may have a good prognosis if completely resected.