From Hazy Opacity to Cystic Nodule: An Atypical Radiologic Course of Pulmonary Metastasis From Colorectal Carcinoma

A 68-year-old man presented to our thoracic surgery department for evaluation of a left upper-lobe pulmonary nodule detected on chest CT scan. The oncologic history extended over 7 years. In December 2014, the patient was diagnosed with colorectal adenocarcinoma (ileocecal junction) by colonoscopy, and he underwent a laparoscopic right hemicolectomy and lymph node dissection. Postoperative pathological examination revealed a grade II-III adenocarcinoma of the ileocecal region (ulcerative type), infiltrating into the muscularis. Surgical margins were free of tumor. No metastasis was identified in the examined lymph nodes, including paracolic (19), paracolic (7), intermediate mesenteric (23), and central vascular (2) lymph nodes, corresponding to a pathologic stage of pT2N0M0. The patient recovered well and was placed on regular follow-up.