title: The Role of Neoadjuvant Therapy in Characterizing Indeterminate Lung Lesions in Patients with Resectable Colorectal Liver Metastases.
abstract: BACKGROUND
  Incidental pulmonary lesions are frequently found during the preoperative evaluation of patients considered for resection of colorectal liver metastases (CRLM), and their presence can confound management decisions. This study investigates the role of clinical and radiologic factors, including response to preoperative systemic chemotherapy, in determining the malignant probability of these lesions.
  
  
  METHODS
  Computed tomography (CT) scans of 33 patients with small (≤1 cm) lung lesions undergoing resection for CRLM after preoperative chemotherapy were reviewed. Radiological features were recorded from three sequential CT scans (baseline, postchemotherapy, and follow-up). Malignancy was diagnosed either by resection or serial imaging. Chemotherapy response comparing lung lesions and CRLM was categorized as: (1) concordant or (2) discordant. Chemotherapy response, imaging features, and other clinical factors were evaluated in multivariate analyses as predictors of malignancy.
  
  
  RESULTS
  Among the 86 indeterminate lung lesions identified, 23 % (20/86) were found to be metastases on follow-up. Lesions 6-10 mm were more likely to be metastases (odds ratio [OR] = 3.14, p = 0.045), as were lesions located in the lower lobes (OR = 4.50, p = 0.018). Concordant chemotherapy response was found in 13 of 86 (15 %) and was independently associated with metastatic disease (OR = 19.87, p < 0.001), with 11 of 13 (85 %) lesions determined to be metastases. In contrast, only 9 of 73 lesions (12 %) with discordant response were found to be metastases.
  
  
  CONCLUSIONS
  Lesion size, location, and chemotherapy response pattern were independent predictors of malignancy for patients with resectable CRLM and small indeterminate lung lesions. Utilization of preoperative chemotherapy can be a useful method of ruling out pulmonary metastases in these patients.
authors.affiliation: Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, USA.
authors.forename: Georgios
authors.initials: G
authors.lastname: Karagkounis
authors.forename: Guoxiang
authors.initials: G
authors.lastname: Cai
authors.forename: Pamela T
authors.initials: PT
authors.lastname: Johnson
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Pawlik
authors.forename: Elliot K
authors.initials: EK
authors.lastname: Fishman
authors.forename: Michael A
authors.initials: MA
authors.lastname: Choti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011379:Prognosis; D014057:Tomography, X-Ray Computed