Risk-stratified surveillance protocol improves cost-effectiveness after radical nephroureterectomy in patients with upper tract urothelial carcinoma

Abstract

// Masaki Momota 1 , Shingo Hatakeyama 1 , Hayato Yamamoto 1 , Hiromichi Iwamura 1, 2 , Yuki Tobisawa 1 , Tohru Yoneyama 3 , Takahiro Yoneyama 1 , Yasuhiro Hashimoto 3 , Takuya Koie 1 , Ikuya Iwabuchi 4 , Masaru Ogasawara 4 , Toshiaki Kawaguchi 4 and Chikara Ohyama 1, 3 1 Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan 2 Department of Urology, Tohoku Medical and Pharmaceutical University, Sendai, Japan 3 Department of Advanced Transplant and Regenerative Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Japan 4 Department of Urology, Aomori Prefectural Central Hospital, Aomori, Japan Correspondence to: Shingo Hatakeyama, email: shingoh@hirosaki-u.ac.jp Keywords: upper tract urothelial carcinoma; radical nephroureterectomy; recurrence; surveillance; cost-effectiveness Received: December 26, 2017      Accepted: April 06, 2018      Published: May 01, 2018 ABSTRACT Objectives: To develop a surveillance protocol with improved cost-effectiveness after radical nephroureterectomy (RNU), as the cost-effectiveness of oncological surveillance after RNU remains unclear. Results: Of 426 patients, 109 (26%) and 113 (27%) experienced visceral and intravesical recurrences, respectively. The pathology-based protocol found significant differences in recurrence-free survival in the visceral recurrence but not in the intravesical recurrence. The medical costs per visceral recurrence detected were high, especially in normal-risk (≤ pT2N0, LVI-, SM-) patients. We developed a risk score associated with visceral recurrence using Cox regression analysis. The risk score-based protocol was significantly more cost-effective than the pathology-based protocol. Estimated cost differences reached $747,929 per recurrence detected, a suggested 55% reduction. Materials and Methods: We retrospectively evaluated 426 patients with RNU for upper tract urothelial carcinoma (UTUC) without distant metastasis at 4 hospitals. Patients with routine oncological follow-up were stratified into normal-, high- and very high-risk groups according to a pathology-based protocol utilizing pathological stage, lymphovascular invasion (LVI) and surgical margin (SM). Cost-effectiveness of the pathology-based protocol was evaluated, and a risk score-based protocol was developed to optimize cost-effectiveness. Risk scores were calculated by summing up risk factors independently associated with recurrence-free survival. Patients were stratified by low-, intermediate- and high-risk score. Estimated cost per recurrence detected by pathology-based and risk score-based protocols was compared. Conclusions: A risk score-stratified surveillance protocol has the potential to reduce over investigation during follow-up, making surveillance more cost-effective.