Development and Applicability of Integrative Tumor Response Assays for Metastatic Colorectal Cancer

YONG SIK YOON, CHAN WOOK KIM, SEON AE ROH, DONG HYUNG CHO, TAE WON KIM, MOON BO KIM and JIN CHEON KIM

Abstract

Aim: The present study investigated how well the results of integrative tumor-response assay (ITRA) compared to those of clinical response to chemotherapy in patients with metastatic colorectal cancer (CRC). 

Patients and Methods: A total of 129 patients with metastatic CRC were prospectively enrolled. ITRA consisted of two sequential histoculture drug-response assays (HDRAs). First-stage HDRAs were performed using 5-fluorouracil with leucovorin and oxaliplatin (FX), or with irinotecan (FR). Second-stage HDRAs (ITRA) were performed for cells surviving after the first-stage HDRA, using FX, FR, and their combinations with bevacizumab and cetuximab. 

Results: Among 129 patients, 42 (32.6%) completed second-line chemotherapy, results that correlated with those of ITRA. The accuracy of ITRA for predicting response to second-line chemotherapy was 61.9% (26/42), with a sensitivity of 44.4% (8/18) and a specificity of 75% (18/24).

Conclusion: Despite its relatively low accuracy, ITRA might be a useful technique for predicting therapeutic efficacy and selecting for appropriate first-line and second-line anticancer regimens for patients.