Assessment of the value of adjuvant radiotherapy for treatment of gastric adenocarcinoma based on pattern of post-surgical progression

Survival prognostic analysis of laparoscopic D2 radical resection for locally advanced gastric cancer: A multicenter cohort study

BACKGROUND

With the development of minimally invasive surgical techniques, the use of laparoscopic D2 radical surgery for the treatment of locally advanced gastric cancer (GC) has gradually increased. However, the effect of this procedure on survival and prognosis remains controversial. This study evaluated the survival and prognosis of patients receiving laparoscopic D2 radical resection for the treatment of locally advanced GC to provide more reliable clinical evidence, guide clinical decision-making, optimize treatment strategies, and improve the survival rate and quality of life of patients.

AIM

To investigate the survival prognosis and influencing factors of laparoscopic D2 radical resection for locally advanced GC patients.

METHODS

A retrospective cohort study was performed. Clinicopathological data from 652 patients with locally advanced GC in our hospitals from December 2013 to December 2023 were collected. There were 442 males and 210 females. The mean age was 57 ± 12 years. All patients underwent a laparoscopic D2 radical operation for distal GC. The patients were followed up in the outpatient department and by telephone to determine their tumor recurrence, metastasis, and survival. The follow-up period ended in December 2023. Normally distributed data are expressed as the mean ± SD, and normally distributed data are expressed as M (Q1, Q3) or M (range). Statistical data are expressed as absolute numbers or percentages; the χ 2 test was used for comparisons between groups, and the Mann-Whitney U nonparametric test was used for comparisons of rank data. The life table method was used to calculate the survival rate, the Kaplan-Meier method was used to construct survival curves, the log rank test was used for survival analysis, and the Cox risk regression model was used for univariate and multifactor analysis.

RESULTS

The median overall survival (OS) time for the 652 patients was 81 months, with a 10-year OS rate of 46.1%. Patients with TNM stages II and III had 10-year OS rates of 59.6% and 37.5%, respectively, which were significantly different (P < 0.05). Univariate analysis indicated that factors such as age, maximum tumor diameter, tumor differentiation grade (low to undifferentiated), pathological TNM stage, pathological T stage, pathological N stage (N2, N3), and postoperative chemotherapy significantly influenced the 10-year OS rate for patients with locally advanced GC following laparoscopic D2 radical resection for distal stomach cancer [hazard ratio (HR): 1.45, 1.64, 1.45, 1.64, 1.37, 2.05, 1.30, 1.68, 3.08, and 0.56 with confidence intervals (CIs) of 1.15-1.84, 1.32-2.03, 1.05-1.77, 1.62-2.59, 1.05-1.61, 1.17-2.42, 2.15-4.41, and 0.44-0.70, respectively; P < 0.05]. Multifactor analysis revealed that a tumor diameter greater than 4 cm, low tumor differentiation, and pathological TNM stage III were independent risk factors for the 10-year OS rate in these patients (HR: 1.48, 1.44, 1.81 with a 95%CI: 1.19-1.84). Additionally, postoperative chemotherapy emerged as an independent protective factor for the 10-year OS rate (HR: 0.57, 95%CI: 0.45-0.73; P < 0.05).

CONCLUSION

A maximum tumor diameter exceeding 4 cm, low tumor differentiation, and pathological TNM stage III were identified as independent risk factors for the 10-year OS rate in patients with locally advanced GC following laparoscopic D2 radical resection for distal GC. Conversely, postoperative chemotherapy was found to be an independent protective factor for the 10-year OS rate in these patients.

[177Lu]Lu-labeled anti-claudin-18.2 antibody demonstrated radioimmunotherapy potential in gastric cancer mouse xenograft models

PURPOSE

Gastric cancer (GC), one of the most prevalent and deadliest tumors worldwide, is often diagnosed at an advanced stage with limited treatment options and poor prognosis. The development of a CLDN18.2-targeted radioimmunotherapy probe is a potential treatment option for GC.

METHODS

The CLDN18.2 antibody TST001 (provided by Transcenta) was conjugated with DOTA and radiolabeled with the radioactive nuclide 177Lu. The specificity and targeting ability were evaluated by cell uptake, imaging and biodistribution experiments. In BGC823CLDN18.2/AGSCLDN18.2 mouse models, the efficacy of [177Lu]Lu-TST001 against CLDN18.2-expressing tumors was demonstrated, and toxicity was evaluated by H&E staining and blood sample testing.

RESULTS

[177Lu]Lu-TST001 was labeled with an 99.17%±0.32 radiochemical purity, an 18.50 ± 1.27 MBq/nmol specific activity and a stability of ≥ 94% after 7 days. It exhibited specific and high tumor uptake in CLDN18.2-positive xenografts of GC mouse models. Survival studies in BGC823CLDN18.2 and AGSCLDN18.2 tumor-bearing mouse models indicated that a low dose of 5.55 MBq and a high dose of 11.10 MBq [177Lu]Lu-TST001 significantly inhibited tumor growth compared to the saline control group, with the 11.1 MBq group showing better therapeutic efficacy. Histological staining with hematoxylin and eosin (H&E) and Ki67 immunohistochemistry of residual tissues confirmed tumor tissue destruction and reduced tumor cell proliferation following treatment. H&E showed that there was no significant short-term toxicity observed in the heart, spleen, stomach or other important organs when treated with a high dose of [177Lu]Lu-TST001, and no apparent hematotoxicity or liver toxicity was observed.

CONCLUSION

In preclinical studies, [177Lu]Lu-TST001 demonstrated significant antitumor efficacy with acceptable toxicity. It exhibits strong potential for clinical translation, providing a new promising treatment option for CLDN18.2-overexpressing tumors, including GC.

Survival benefit after neoadjuvant or adjuvant radiotherapy for stage II–III gastroesophageal junction adenocarcinoma: A large population-based cohort study

Objective

The standard treatment for stage II–III gastroesophageal junction adenocarcinoma (GEJA) remains controversial, and the role of radiotherapy (RT) in stage II–III GEJA is unclear. Herein, we aimed to evaluate the prognosis of different RT sequences and identify potential candidates to undergo neoadjuvant RT (NART) or adjuvant RT (ART).

Materials and methods

In total, we enrolled 3,492 patients with resectable stage II–III GEJA from the Surveillance, Epidemiology, and End Results (SEER) database, subsequently assigned to three categories: T_1–2N⁺, T_3–4N⁻, and T_3–4N⁺. Survival curves were evaluated using the Kaplan–Meier method along with the log-rank test. We compared survival curves for NART, ART, and non-RT in the three categories. To further determine histological types impacting RT-associated survival, we proposed new categories by combining the tumor, node, and metastasis (TNM) stage with Lauren’s classification.

Results

ART afforded a significant survival benefit in patients with T_1–2N⁺ and T_3–4N⁺ tumors. In addition, NART conferred a survival advantage in patients with T_3–4N⁺ and T_3–4 exhibiting the intestinal type. Notably, ART and NART were both valuable in patients with T_3–4N⁺, although no significant differences between treatment regimens were noted.

Conclusions

Both NART and ART can prolong the survival of patients with stage II–III GEJA. Nevertheless, the selection of NART or ART requires a concrete analysis based on the patient’s condition.

The Incidence-Based Mortality and Survival Trends in Patients with Gastric Signet Ring Cell Carcinoma

Background and Aim. Gastric signet ring cell carcinoma (SRC) is a distinct subtype of gastric cancer. This study aims to analyze the incidence-based mortality and survival trends in patients with gastric SRC over the past decades. Materials and Methods. The patients from the Surveillance, Epidemiology, and End Results (SEER) database were recruited to explore the incidence-based mortality and survival trends from 2000 to 2017. We further analyzed the differences in mortality and survival trends in these patients by sex and stage. We also used joinpoint software to evaluate the trends in annual percentage change (APC) for statistical significance. Results. 14916 patients were collected, including 7801 (52.3%) male and 7115 (47.7%) female. We identified a single joinpoint at 2002. The overall incidence-based mortality of gastric SRC declined in America after 2002 (APC = −1.21, $P<0.05$ ). In stratified analysis by sex and stage, the incidence-based mortality rate was higher in males than females. After 2002, the mortality rate decreased significantly in male (APC = −1.68, $P<0.05$ ) and M0-stage patients (APC = −1.75, $P<0.05$ ). In survival trend analysis, the 2-year relative survival improved in M0-stage gastric SRC, especially for males (APC = 1.14, $P<0.05$ ). As for M1-stage patients, the 2-year relative survival significantly elevated in both male (APC = 3.87, $P<0.05$ ) and female (APC = 5.63, $P<0.05$ ) patients. Conclusions. The incidence-based mortality of gastric SRC has declined, and survival has improved in America over time. These optimistic trends may be attributed to cancer screening implementation and advances in novel treatments in the past decades.

A population-based predictive model to identify patients with signet ring cell carcinoma of the stomach who are most suitable for primary tumor resection

Background

Though the survival benefit of primary tumor operation for patients with signet ring cell carcinoma of the stomach is known, the specific characteristics of those patients who would profit from the operation are yet to be determined. To this end, a predictive model was developed to identify the conjecture that the survival profit from primary tumor operation would only be obtained by patients.

Method

The clinical data of the patients with signet ring cell carcinoma of the stomach were obtained from the Surveillance, Epidemiology, and End Results database, and then divided into operation and no-operation groups based on whether the patients underwent the primary tumor operation. To remove the confounding factors, propensity score matching was employed, and it was hypothesized that the patients who had been operated on and lived a longer life than the median cancer-specific survival time of those who hadn’t must have profited from the surgery. To discuss the independent factors of cancer-specific survival time in the beneficial group and the non-beneficial group, the Cox model was used, and based on the various vital predictive factors, a nomogram was drawn using logistic regression.

Result

The number of eligible patients was 12,484, with 43.9% (5483) of them having received surgery. After employing propensity score matching, the cancer-specific survival time of the operation group was found to be apparently longer (median: 21 vs. 5 months; p < 0.001) than the no-operation group. In the operation group, 4757 (86.7%) of the patients lived longer than five months (beneficial group). The six indexes (beneficial and non-beneficial group) included gender, age, Tumor Node Metastasis stage, histologic type, differentiation grade, and tumor position, and were used as predictors to draw the nomogram. The nomogram was used to divide the patients who had taken operations into two groups: the beneficial operation group and the non-beneficial operation group. The beneficial operation group, it was found, survived longer than the non-beneficial operation group (median cancer-specific survival time: 28 vs. 3 months, p < 0.001). Moreover, there was we could tell little difference in survival between the two groups (median cancer-specific survival time: 3 vs. 5 months).

Conclusions

The predictive model created to select suitable candidates for surgical treatment from patients with signet ring carcinoma of the stomach could be adopted to identify certain patients benefiting from the primary tumor operation.