Early Tumor Shrinkage and Depth of Response Evaluation in Metastatic Pancreatic Cancer Treated with First Line Chemotherapy: An Observational Retrospective Cohort Study

Abstract

Early tumor shrinkage (ETS) and depth of response (DoR) predict favorable outcomes in metastatic colorectal cancer. We aim to evaluate their prognostic role in metastatic pancreatic cancer (PC) patients treated with first-line modified-FOLFIRINOX (FOLFOXIRI) or Gemcitabine + Nab-paclitaxel (GemNab). Hence, 138 patients were tested for ETS, defined as a ≥20% reduction in the sum of target lesions’ longest diameters (SLD) after 6–8 weeks from baseline, and DoR, i.e., the maximum percentage shrinkage in the SLD from baseline. Association of ETS and DoR with progression-free survival (PFS) and overall survival (OS) was assessed. ETS was reached in 49 patients (39.5% in the FOLFOXIRI, 29.8% in the GemNab group; p = 0.280). In the overall population, ETS was significantly associated with better PFS (8.0 vs. 4.8 months, p < 0.001) and OS (13.2 vs. 9.7 months, p = 0.001). Median DoR was −27.5% (−29.4% with FOLFOXIRI and −21.4% with GemNab, p = 0.016): DoR was significantly associated with better PFS (9.0 vs. 6.7 months, p < 0.001) and OS (14.3 vs. 11.1 months, p = 0.031). Multivariate analysis confirmed both ETS and DoR are independently associated with PFS and OS. In conclusion, our study added evidence on the role of ETS and DoR in the prediction of outcome of PC patients treated with first-line combination chemotherapy.

Early Tumor Shrinkage as a Predictive Factor for Outcomes in Hepatocellular Carcinoma Patients Treated with Lenvatinib: A Multicenter Analysis

“…Here, we clearly identified an ETS value of 10% as the optimal cut-off for predicting a long-term response to LEN (PFS ≥ 5.0 months), based on ROC analysis. This finding is in line with previous reports of various malignancies treated with chemotherapy including targeted therapies, using a range of ETS cut-off values (10%-30%) to determine predictors of PFS and OS [6][7][8][9][10][11]. Additionally, when we used the standard cut-off value for objective response, that is, ETS ≥ 30%, the specificity for predicting PFS was considerably worse, compared with ETS ≥ 10%, because only 15% of the patients achieved that ETS.…”

“…Treatment activity was evaluated according to the RECIST (version 1.0) guidelines by two hepatic physicians at Kyoto Prefectural University of Medicine. ETS was defined as a relative change in the sum of longest diameters of RECIST target lesions at the first evaluation (6-8 weeks after starting LEN) compared with baseline, consistent with previous studies on ETS [6][7][8][9][10][11]. RECIST target lesions were all measurable lesions up to a maximum of five lesions per organ and 10 lesions in total.…”

“…Early tumor shrinkage (ETS) is defined as a reduction in tumor size at the first radiologic evaluation (i.e., at eight weeks after treatment initiation) [6]. A correlation between ETS and treatment outcome has been reported in many malignancies such as metastatic colorectal cancer [6][7][8], pancreatic cancer [9], renal cell carcinoma [10], and non-small cell lung cancer [11]. The benefit of utilizing ETS as a marker is that it might enable earlier prediction of drug activity compared with conventional end points such as progression-free survival (PFS) and overall survival (OS).…”

“…This study aimed to evaluate the prognostic role of ETS, as well as identify the optimal cut-off value of ETS in HCC patients treated with LEN. We adopted the RECIST criteria to evaluate treatment response, corresponding with previous studies on ETS [6][7][8][9][10][11].…”

Tailored Systemic Therapy for Colorectal Cancer Liver Metastases

“…Overall, studies demonstrate improved long-term outcomes for patients responding to conversion therapy and undergoing secondary resection. Re-evaulation for treatment response and resectability should be performed early and every two months, in order to prevent overtreatment of secondarily resectable patients [53].…”