An Accurate Diagnosis of Noguchi Classification Is Possible after the Modification of Preoperative Biopsy-Induced Fibrosis

Yuki Nakajima, MD,1,2 Masashi Kawamoto, MD, PhD,2,3,5 Kiyoshi Koizumi, MD, PhD,1 Hiroyuki Tajima, MD, PhD,4 Yuh Fukuda, MD, PhD,2 Shin-ichi Tsuchiya, MD, PhD,5 and Kazuo Shimizu, MD, FACS1

Purpose: After computed-tomography–guided needle biopsy (CTNB), the lung may undergo iatrogenic fibrosis (post-CTNB fibrosis), which can be misdiagnosed as tumor-induced fibrosis. The purpose of the study was to examine if an accurate evaluation of pulmonary adenocarcinoma can be made using the Noguchi classification (type A or B vs. type C), even after CTNB.
Materials and Methods: The subjects were 71 patients with primary pulmonary adenocarcinoma of 20 mm or less that had been resected surgically after CTNB. Twenty-four patients who did not undergo a preoperative biopsy served as controls. Resected specimens were stained with hematoxylin-eosin (HE) and elastic-fiber staining for a precise observation of fibrosis.
Results: The period from CTNB to surgery ranged from 12 to 153 days. Post-CTNB fibrosis consisted primarily of collagen fibers with a few thin elastic fibers observed only with high magnification, which was able to distinguish post-CTNB fibrosis in 39 of 48 patients (81.3%) with bronchioloalveolar carcinoma (BAC) lesions (types A/B/C) and in 6 of 23 patients (26.1%) without BAC lesions (types D/E/F/E + F), showing a significant difference (p <0.0001). In the control group, no lesions that resembled post-CTNB fibrosis were observed.
Conclusion: An evaluation of pulmonary adenocarcinoma by Noguchi classification can be accurately performed even after CTNB. (Ann Thorac Cardiovasc Surg 2009; 15: 221-226)

Key words: bronchioloalveolar carcinoma, computed-tomography–guided needle biopsy, fibrosis, lung cancer, Noguchi classification

1Division of Thoracic Surgery, Department of Surgery; 2Departments of Analytic Human Pathology, 3Integrative Oncological Pathology, and 4Radiology, Graduate School of Medicine, Nippon Medical School; and 5Division of Diagnostic Pathology, Nippon Medical School Hospital, Tokyo, Japan

Received May 1, 2008; accepted for publication July 14, 2008
Address reprint requests to Yuki Nakajima, MD: Division of Thoracic Surgery, Department of Surgery, Nippon Medical School Hospital, 1–1–5 Sendagi, Bunkyo-ku, Tokyo 113–8603, Japan.