title: Histology is a Prognostic Indicator After Pulmonary Metastasectomy from Renal Cell Carcinoma.
abstract: There are only a few detailed reports concerning the prognosticators following surgical resection of pulmonary metastases (PMs) from renal cell carcinoma (RCC). We investigated the prognosis of patients with RCC PMs undergoing pulmonary metastasectomy and identified prognostic factors in a multi-institutional retrospective study.
  
  
  
  We retrospectively evaluated 84 patients who underwent resection of PMs from RCC between 1993 and 2014. We assessed the clinicopathological characteristics, focusing on the histological findings of PMs. We classified the histology into three types: pure clear cell carcinoma (N = 68), clear cell carcinoma combined with other histology type (N = 8), and non-clear cell carcinoma (N = 8). We examined the relationship between these histological types and the prognosis of patients with PMs from RCC.
  
  
  
  Complete resection was achieved in 78 patients (93%). The 5-year overall survival rate after metastasectomy was 59.7%. In multivariate analysis, three factors were found to be independent favorable prognostic factors of overall survival after lung metastasectomy [tumor size <2 cm, hazard ratio (HR) = 0.31, 95% confidence interval (CI) 0.13-0.78, P = 0.012; clear cell type, HR = 0.37, 95% CI 0.16-0.83, P = 0.025; and complete resection, HR = 0.27, 95% CI 0.10-0.78, P = 0.015].
  
  
  
  This study indicates that a histological finding of the clear cell type is a significant favorable prognostic factor in addition to complete resection and a tumor size <2 cm. Histological evaluation of PM lesions is important for predicting survival after metastasectomy.
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan.|Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ohtaki
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan. kmshimizu@gmail.com.|Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan. kmshimizu@gmail.com.
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Division of Thoracic Surgery, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
authors.forename: Keiju
authors.initials: K
authors.lastname: Aokage
authors.affiliation: Department of Thoracic Surgical Oncology, The Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakao
authors.affiliation: Division of Thoracic Surgery, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Yoshida
authors.affiliation: Department of General Thoracic Surgery, Maebashi Red Cross Hospital, Maebashi, Gunma, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kamiyoshihara
authors.affiliation: Department of General Thoracic Surgery, National Hospital Organization Takasaki General Medical Center, Takasaki, Gunma, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sugano
authors.affiliation: Department of General Thoracic Surgery, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan.|Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Seshiru
authors.initials: S
authors.lastname: Nakazawa
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan.|Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Toshiteru
authors.initials: T
authors.lastname: Nagashima
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan.|Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Kai
authors.initials: K
authors.lastname: Obayashi
authors.affiliation: Division of Thoracic Surgery, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Hishida
authors.affiliation: Division of Thoracic Surgery, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tsuboi
authors.affiliation: Department of Thoracic Surgical Oncology, The Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Shohei
authors.initials: S
authors.lastname: Mori
authors.affiliation: Department of Thoracic Surgical Oncology, The Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Mingyon
authors.initials: M
authors.lastname: Mun
authors.affiliation: Department of Thoracic Surgical Oncology, The Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Sakae
authors.initials: S
authors.lastname: Okumura
authors.affiliation: Department of General Thoracic Surgery, Maebashi Red Cross Hospital, Maebashi, Gunma, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Igai
authors.affiliation: Department of General Thoracic Surgery, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Matsutani
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Mogi
authors.affiliation: Division of General Thoracic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kuwano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000473:pathology* / Q000556:secondary / Q000601:surgery*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality / Q000473:pathology; D008175:Lung Neoplasms / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D008297:Male; D059146:Metastasectomy; D008875:Middle Aged; D011013:Pneumonectomy; D011379:Prognosis; D012189:Retrospective Studies