Interpretation of core biopsy of liver mass lesions: A comparison study between cytopathologist and gastrointestinal pathologist.

CONTEXT: Core biopsy (CB) is a main tool for diagnosis of liver mass lesions. When CB is performed with fine needle aspiration (FNA), the CB may be interpreted by a cytopathologist or gastrointestinal pathologist.

OBJECTIVE

This study compares interpretation of liver mass biopsy between cytopathologist and gastrointestinal pathologist in the era of subspecialty practice.

DESIGN

349 liver mass lesions with FNA and CB performed during a 5-year period were retrieved. All cases were initially interpreted by a cytopathologist and retrospectively reviewed by a gastrointestinal pathologist.

RESULTS

The overall agreement was 95.1% (332/349 cases). There was agreement on 57/65 non-neoplastic cases (87.7%) with 8 (12.3%) discordant cases including 4 steatosis (steatohepatitis missed in 3 cases, 1 re-interpreted as focal nodular hyperplasia [FNH]); 3 inflammation (1 necrotizing granulomatous inflammation, 1 massive necrosis instead of fibrosing cholestatic hepatitis, and 1 hepatocellular carcinoma [HCC] was missed); and 1 initially deemed normal re-interpreted as FNH. There was agreement on 275/284 neoplastic cases (96.8%), with 9 (3.2%) discordant cases including: 2 initially interpreted as HCC (1 metastatic adrenal cortical carcinoma, 1 cholangiocarcinoma); 3 adenocarcinomas (2 further defined as prostatic primary, 1 well-differentiated neuroendocrine tumor [WDNET]); 2 metastatic carcinomas (1 tumor-induced fibrosis instead of cirrhosis, 1 LCNEC re-interpreted as WDNET); 1 poorly differentiated carcinoma (re-interpreted as LCNEC); and 1 sarcomatoid carcinoma (re-interpreted as leiomyosarcoma).

CONCLUSION

Cytopathologist and gastrointestinal pathologist are highly concordant in the interpretation of neoplastic liver mass CB. Consultation may improve accuracy in certain non-neoplastic biopsies and neuroendocrine neoplasms.