En Bloc Diaphragmatic Resection for Hepatocellular Carcinoma with Diaphragmatic Invasion, a Propensity Score Matched Analysis

Abstract

Aim: This study aimed to evaluate the impact of en bloc diaphragmatic resection (DR) in patients with hepatocellular carcinoma(HCC). Method: Patients who received DR at the time of hepatectomy for HCC between 1997 to 2017 were retrospectively identified on a prospectively maintained database. Outcomes were compared to HCC patients without DR using propensity score matching(PSM) of 1:4 by controlling for alpha-fetoprotein levels and UICC staging. Results: During study period, 1744 patients received hepatectomy for HCC. Amongst them, 122 had en bloc DR, with 38 showing diaphragmatic invasion on histopathology. The diaphragm was repaired either primarily(n=112) or by mesh repair(n=10). Patients who required DR were more symptomatic on presentation, with higher AFP levels, larger tumour size, and more advanced UICC staging(P<0.001). After PSM, 122 patients with DR were matched to 488 patients without DR. Patients in the DR group were more likely to require major hepatectomy(87.7% vs. 73.6%, P=0.001), with higher risk of developing pulmonary complications(27.1% vs. 19.1%, P=0.007) and severe complication(27% vs. 14.1%, P=0.001). There was no difference in pathological UICC staging, but patients with DR were more likely to develop extrahepatic metastasis(21.3% vs. 12.7%, P=0.102). 5-year OS were 28.1% and 39.2%(P=0.009), while 5-year DFS were 17.9% and 23.4%(P=0.251) for the DR and non-DR groups respectively. Preoperative albumin, AFP, UICC stage, involved resection margin and the need for ICU support were associated with poor DFS but DR was not prognostic. Conclusion: HCC with diaphragmatic invasion was associated with poor tumor pathology and higher risk of postoperative pulmonary complications.