title: Response evaluation criteria in solid tumors response of the primary lesion in metastatic renal cell carcinomas treated with sunitinib: does the primary lesion have to be regarded as a target lesion?
abstract: BACKGROUND
  We evaluated whether best overall response changes by designating primary renal lesions as either target or nontarget lesions and assessing response per Response Evaluation Criteria in Solid Tumors in mRCC patients treated with sunitinib. In addition, we evaluated whether discordance, if any, leads to a difference in predictive value of response in terms of time to progression (TTP) and overall survival (OS).
  
  
  METHODS
  Patients with mRCC with an intact primary tumor and at least 1 extrarenal measurable lesion were included in this study. The variation of the sum of diameters (ΔSOD) of target lesions and best overall response, assessed from all target lesions and from metastasis-only target lesions, was documented separately.
  
  
  RESULTS
  There were 41 patients included. Median ΔSOD of the primary lesion and metastatic target lesion were -6.0% (range, -34.0% to 17.6%), and -18.0% (range, -100.0% to 120.0%), respectively. For metastasis-only target lesions, the best overall response of 2 patients (4.9%) changed from stable disease to partial response. When we categorized patients into responders and nonresponders, response determination using metastasis-only target lesions resulted in significantly better discrimination of time to progression (14.9 vs. 4.3 months, P = .001) and overall survival (18.5 vs. 9.6 months, P = .036) between 2 groups. Using all target lesions, both TTP (14.9 vs. 5.4 months, P = .056) and OS (18.0 vs. 10.6 months, P = .155) were not statistically significant.
  
  
  CONCLUSIONS
  When treating nonnephrectomized mRCC patients, selecting metastasis-only lesions as target lesions might be better to determine response, which might be more representative of survival end point.
authors: Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Inkeun
authors: I
authors: Park
authors: Kwonoh
authors: K
authors: Park
authors: Seongjoon
authors: S
authors: Park
authors: Yongcheol
authors: Y
authors: Ahn
authors: Jin-Hee
authors: JH
authors: Ahn
authors: Hyuck Jae
authors: HJ
authors: Choi
authors: In Gab
authors: IG
authors: Jeong
authors: Cheryn
authors: C
authors: Song
authors: Jun Hyuk
authors: JH
authors: Hong
authors: Choung-Soo
authors: CS
authors: Kim
authors: Hanjong
authors: H
authors: Ahn
authors: Jae-Lyun
authors: JL
authors: Lee
mesh_terms: D000328:Adult; D000368:Aged; D020533:Angiogenesis Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D002292:Carcinoma, Renal Cell / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D005260:Female; D006801:Humans; D007211:Indoles / Q000009:adverse effects / Q000627:therapeutic use*; D007668:Kidney / Q000187:drug effects / Q000473:pathology / Q000601:surgery; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000188:drug therapy*; D009392:Nephrectomy; D011758:Pyrroles / Q000009:adverse effects / Q000627:therapeutic use*; D012189:Retrospective Studies; D000077210:Sunitinib; D013534:Survival; D016896:Treatment Outcome
chemical_list: D020533:Angiogenesis Inhibitors; D007211:Indoles; D011758:Pyrroles; D000077210:Sunitinib
keywords: Primary lesion; RCC; RECIST; Sunitinib; Target lesion