Pretreatment assessment of tumor enhancement on contrast-enhanced computed tomography as a potential predictor of treatment outcome in metastatic renal cell carcinoma patients receiving antiangiogenic therapy.
BACKGROUND
Tumor vascularity is a potential predictor of treatment outcomes in metastatic renal cell carcinoma (mRCC), and contrast enhancement of tumors in computed tomography (CT) is correlated significantly with microvessel density. In this study, the authors investigated whether tumor enhancement in contrast-enhanced CT (CECT) is useful for predicting outcomes in patients with mRCC who are receiving antiangiogenic therapy.


METHODS
Attenuation values were reviewed retrospectively on CECT images of all metastatic lesions in 66 patients from February 2007 to November 2008. All patients received a tyrosine kinase inhibitor (either sunitinib or sorafenib). Tumor response was evaluated on CECT studies every 12 weeks. The authors analyzed the association between contrast enhancement and treatment outcomes, including objective response, tumor size reduction rate, time to response, and time to progression.


RESULTS
In 46 patients, 198 metastatic lesions were assessed. Tumor size was reduced in 140 lesions (70.7%) and was increased in 58 lesions (29.3%). The mean reduction in size was 23.8%. The overall mean time to response and the time to progression were 8.6 months and 16.4 months, respectively. In multivariate analyses, tumor enhancement and enhancement pattern were associated with objective responses (P = .003 and P = .028, respectively). In addition, tumor enhancement was associated with tumor size reduction (P = .004). In Cox proportional hazards models, only tumor enhancement was associated significantly with the time to size reduction and progression-free survival (P = .03 and P = .015, respectively).


CONCLUSIONS
Tumor enhancement on CECT images was associated with treatment outcomes and was identified as a potential predictor of treatment outcomes after antiangiogenic therapy in patients with mRCC.
Department of Urology and Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
Kyung Seok
KS
Han
Dae Chul
DC
Jung
Hyuck Jae
HJ
Choi
Min Soo
MS
Jeong
Kang Su
KS
Cho
Jae Young
JY
Joung
Ho Kyung
HK
Seo
Kang Hyun
KH
Lee
Jinsoo
J
Chung
D000328:Adult; D000368:Aged; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging; D003287:Contrast Media; D018450:Disease Progression; D016503:Drug Delivery Systems; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging*; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
D020533:Angiogenesis Inhibitors; D003287:Contrast Media; D047428:Protein Kinase Inhibitors