Better Cancer-specific Survival in Younger Patients With Stage III Colorectal Cancer: A Propensity Score Matching Study From Japan

Abstract

Background/Aim: The purpose of this study was to explore the perioperative, short-term, and long-term prognostic differences in colorectal cancer (CRC) between young and older patients. Patients and Methods: A total of 3095 patients were divided into young (≤45 years; n=139) and older (>45 years; n=2956) groups. Then, propensity score matching was performed for patients in stage I to III according to a ratio of 1:1. The clinicopathological factors and prognosis of the two groups were studied. Results: Young patients with CRC account for 4.49% of the total number of patients with CRC. Younger patients with CRC in stage I to III showed better cancer-specific survival (CSS). Older age was an independent risk factor for CSS prognosis. The CSS of the younger group was significantly better in stage I to III as a whole, but there was no difference in stage I and II subgroups -only in stage III. The proportion of young patients with stage III disease receiving first-line adjuvant chemotherapy was significantly higher. When young patients relapsed, they were more likely to receive second-line adjuvant chemotherapy or reoperation than older patients. Conclusion: Younger patients with stage III colorectal cancer had better CSS rates.

The short-term and oncologic outcomes of younger VS older colorectal cancer patients undergoing primary surgery: a propensity score matching analysis

“…However, the cut-off age of younger CRC patients was different in previous studies, and the cut-off age included 30, 35, 40, 45 and 50 years old [ 8 – 12 , 15 – 18 ]. In this study, we used 45 years old as the cut-off of younger and older CRC patients, which was according to the recommended screening age and previous studies [ 6 , 8 , 12 , 15 ]. In addition, PSM was used in this study to analyze the different outcomes between younger aged group and older aged group.…”

“…However, another study reported a better prognosis for younger patients [ 8 ]. We summarized the previous studies which reported the age on the outcomes of CRC patients in Table 5 [ 8 – 12 , 15 – 18 ]. As was shown in the table, OS, DFS, CSS (cancer-specific survival) and short-term outcomes were the main indicators.…”

“…As was shown in the table, OS, DFS, CSS (cancer-specific survival) and short-term outcomes were the main indicators. Moreover, short-term outcomes were reported in two studies, which were relatively small [ 12 , 17 ]. Furthermore, no previous studies reported the age on the survival outcomes of specific tumor stages.…”

“…Therefore, in order to explore the effect of age on each specific tumor stage, Kaplan-Meier was used and we found that younger aged group had better OS than older aged group in stage II and stage IV CRC, and younger aged group had better DFS than older aged group in stage II CRC. The mechanism was unclear, and it was found in a previous study that younger patients had better prognosis in stage III CRC [ 12 ], so more researches are needed on specific tumor stage in the future.…”

“…Some studies reported that younger CRC patients had better prognosis [ 8 ], however, other studies reported younger CRC patients were associated with poorer prognosis [ 9 – 11 ]. Furthermore, there was only one study which analyzed the difference between younger and older CRC patients using a propensity score matching (PSM) analysis, however, this study focused on cancer-specific survival [ 12 ]. Therefore, the purpose of this study is to analyze the difference of short-term outcomes, overall survival (OS) and disease-free survival (DFS) between younger and older CRC patients who underwent primary CRC surgery using PSM.…”