Patterns of recurrence after curative D2 resection for gastric cancer: Implications for postoperative radiotherapy

Circulating tumor cells are a good predictor of tumor recurrence in clinical patients with gastric cancer

Circulating tumor cells (CTCs) as a liquid biopsy have great potential in clinical applications and basic cancer research, but their clinical use in gastric cancer remains unclear. This study investigated whether CTCs could be used as a potential prognosis predictor in patients with gastric cancer. A total of 120 patients with pathologically confirmed gastric cancer were enrolled from January 1, 2015, to December 1, 2019. All patients were initially diagnosed without previous treatment, and then the number of CTCs was detected using the NEimFISH method before radical surgical resection. Regular follow-up was performed in all patients, and the correlations between the number of CTCs and clinical endpoints, such as disease-free survival (DFS) and overall survival (OS), were evaluated. The univariate and multivariate hazard ratios were calculated using the Cox proportional hazard model. Based on the number of CTCs, we defined CTCs ≥ 2 per 7.5 mL of whole blood as the positive group and CTCs < 2 as the negative group. Among the 120 patients who underwent CTC detection before surgery, the rate of CTC-positive patients was 64.17% (77/120) of which stage I and II patients accounted for 22.50% and stage III patients accounted for 41.67% (P = 0.014). By detecting CTCs before surgery and at the time of recurrence, the number of CTCs tends to increase concomitantly with disease progression (median: 2 VS 5 per 7.5 mL). Multivariate analysis showed that age (HR, 0.259; 95% CI, 0.101-0.662; P = 0.005), D-dimer (HR, 3.146; 95% CI, 1.169-8.461; P = 0.023), and lymph node metastasis (HR, 0.207; 95% CI, 0.0071-0.603; P = 0.004) were factors correlated with CTCs. In addition, the median follow-up of all the patients was 38.0 months (range of 28-80 months); the DFS in CTC-positive patients was significantly shorter than that of the CTC-negative patients, and a significant difference was found based on the Cox proportional hazard regression model analysis (44.52 ± 2.83 m vs. 74.99 ± 2.78 m, HR = 4.550, P = 0.018). The OS was shorter in the CTC-positive group than in the CTC-negative group before the operation, but the result was not significant based on the Cox proportional hazard regression model analysis (47.58 ± 2.46 m vs. 70.68 ± 3.53 m, HR = 2.261, P = 0.083). The number of CTCs tends to increase concomitantly with disease progression. In addition, the detection of CTCs was an independent predictor of shorter DFS in gastric cancer. However, the relationship between CTCs and OS needs to be determined in future studies.

Role of Preoperative Radiation Therapy for Resectable Gastric Cancer

PURPOSE

While surgery is the primary curative treatment for resectable gastric and gastroesophageal junction (GEJ) cancer, rates of locoregional and distant recurrence remain high with surgery alone, especially in more advanced disease. Multimodal approaches with perioperative therapy including chemotherapy and/or radiation therapy (RT) have thus evolved as ways to reduce the rates of disease recurrence and improve survival outcomes. This review article provides a comprehensive literature review on the role of preoperative RT for resectable gastric and GEJ cancer.

METHODS

A literature review on the role of preoperative RT for resectable gastric and GEJ cancer was conducted.

RESULTS

Preoperative RT has the potential to facilitate tumor downstaging and improved R0 resection, allowing for better locoregional control and thereby survival. For resectable locally advanced GEJ cancer, preoperative chemoradiotherapy (CRT) is currently a standard of care option along with perioperative chemotherapy, based on evidence from randomized trials. In resectable gastric cancer, however, the role of preoperative CRT is less defined with no randomized data to date, although phase II single-arm studies have shown promising results. Current standard of care for gastric cancer remains perioperative chemotherapy, with consideration for preoperative CRT in select cases.

CONCLUSION

Results from ongoing and future randomized controlled trials are expected to help define the role of preoperative CRT compared to perioperative chemotherapy alone as well as postoperative CRT for gastric and GEJ cancer.

Development and validation of nomogram for predicting early recurrence after radical gastrectomy of gastric cancer

BACKGROUND

After radical surgery, early detection of recurrence and metastasis is a crucial factor in enhancing the prognosis and survival of patients with gastric cancer (GC). Therefore, assessing the risk of recurrence in gastric cancer patients and determining the timing for postoperative recurrence is crucial.

METHODS

The clinicopathological data of 521 patients with recurrent gastric cancer, who underwent radical gastrectomy at Zhejiang Cancer Hospital between January 2010 and January 2017, were retrospectively analyzed. These patients were randomly divided into two groups: a training group (n = 365) and a validation group (n = 156). In the training set, patients were further categorized into early recurrence (n = 263) and late recurrence (n = 102) groups based on a 2-year boundary. Comparative analyses of clinicopathological features and prognoses were conducted between these two groups. Subsequently, a nomogram for predicting early recurrence was developed and validated.

RESULTS

In this study, the developed nomogram incorporated age, serous infiltration, lymph node metastasis, recurrence mode, and the tumour marker CA19-9. In the training cohort, the area under the curve (AUC value) was 0.739 (95% CI, 0.682-0.798), with a corresponding C-index of 0.739. This nomogram was subsequently validated in an independent validation cohort, yielding an AUC of 0.743 (95% CI, 0.652-0.833) and a C-index of 0.743. Furthermore, independent risk factors for prognosis were identified, including age, absence of postoperative chemotherapy, early recurrence, lymph node metastasis, abdominal metastasis, and vascular cancer embolus.

CONCLUSION

Independent risk factors for gastric cancer recurrence following radical surgery were utilized to construct a nomogram for predicting early relapse. This nomogram effectively assesses the risk of recurrence, aids in treatment decision-making and follow-up planning in clinical settings, and demonstrated strong performance in the validation cohort.

Laparoscopic Versus Robotic Gastric Cancer Surgery: Short-Term Outcomes-Systematic Review and Meta-Analysis of 25,521 Patients

Background: Gastric cancer has the third highest cancer-related mortality worldwide. There is no consensus regarding the optimal surgical technique to perform curative resection surgery. Objective: Compare laparoscopic gastrectomy (LG) and robotic gastrectomy (RG) regarding short-term outcomes in patients with gastric cancer. Materials and Methods: This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the following topics: "Gastrectomy," "Laparoscopic," and "Robotic Surgical Procedures." The included studies compared short-term outcomes between LG and RG. Individual risk of bias was assessed with the Methodological Index for Non-Randomized Studies (MINORS) scale. Results: There was no significant difference between RG and LG regarding conversion rate, reoperation rate, mortality, overall complications, anastomotic leakage, distal and proximal resection margin distances, and recurrence rate. However, mean blood loss (mean difference [MD] -19.43 mL, P < .00001), length of hospital stay (MD -0.50 days, P = .0007), time to first flatus (MD -0.52 days, P < .00001), time to oral intake (MD -0.17 days, P = .0001), surgical complications with a Clavien-Dindo grade ≥III (risk ratio [RR] 0.68, P < .0001), and pancreatic complications (RR 0.51, P = .007) were significantly lower in the RG group. Furthermore, the number of retrieved lymph nodes was significantly higher in the RG group. Nevertheless, the RG group showed a significantly higher operation time (MD 41.19 minutes, P < .00001) and cost (MD 3684.27 U.S. Dollars, P < .00001). Conclusion: This meta-analysis supports the choice of robotic surgery over laparoscopy concerning relevant surgical complications. However, longer operation time and higher cost remain crucial limitations. Randomized clinical trials are required to clarify the advantages and disadvantages of RG.

Soluble factors in malignant ascites promote the metastatic adhesion of gastric adenocarcinoma cells

BACKGROUND

Adenocarcinoma of the proximal stomach is the fastest rising malignancy in North America. It is commonly associated with peritoneal accumulation of malignant ascites (MA), a fluid containing cancer and inflammatory cells and soluble proteins. Peritoneal metastasis (PM) is the most common site of gastric cancer (GC) progression after curative-intent surgery and is the leading cause of death among GC patients.

METHODS/RESULTS

Using a panel of gastric adenocarcinoma cell lines (human: MKN 45, SNU-5; murine: NCC-S1M), we demonstrate that prior incubation of GC cells with MA results in a significant (> 1.7-fold) increase in the number of cells capable of adhering to human peritoneal mesothelial cells (HPMC) (p < 0.05). We then corroborate these findings using an ex vivo PM model and show that MA also significantly enhances the ability of GC cells to adhere to strips of human peritoneum (p < 0.05). Using a multiplex ELISA, we identify MIF and VEGF as consistently elevated across MA samples from GC patients (p < 0.05). We demonstrate that agents that block the effects of MIF or VEGF abrogate the ability of MA to stimulate the adhesion of GC cells to adhere to human peritoneum and promote both ex vivo and in vivo metastases.

CONCLUSION

Agents targeting MIF or VEGF may be relevant to the treatment or prevention of PM in GC patients.

Systemic Immune-Inflammation Index as a Prognostic Marker of Late Recurrence in Operable Gastric Cancer: a Dual-Center Study

AIM

To evaluate the prognostic role of the systemic immune-inflammation index (SII) in patients with operable gastric cancer.

METHODS

We assessed 354 patients with operable gastric cancer from tertiary centers in Turkey. SII was calculated by following formula: [neutrophil (cells × 10⁹/L) × platelet (cells × 10⁹/L)]/lymphocyte (cells × 10⁹/L). The best cut-off value for SII was determined by using "receiver operating characteristics (ROC)" analysis. We used log-rank and Cox-regression analysis for survival analyses.

RESULTS

One hundred twenty patients were in the late recurrence group (recurrences have developed 36 months after the surgery). SII was not a prognostic factor in the early recurrence group. However, relapse-free survival (RFS) was longer in SII-low patients than SII-high patients in the late recurrence group. In multivariable analysis, SII was the only independent prognostic factor for RFS in the late recurrence group (hazard ratio (HR): 5.42, 95% CI: 1.18-24.82, p = 0.03).

CONCLUSION

SII was an independent prognostic factor for RFS in GC patients with late recurrence. Late recurrence risk was higher in SII-high patients than SII-low patients. Inflammation contributes to tumor progression, invasion, and metastasis. Prolonged exposure to chronic inflammation could explain the results of this study.

A Pilot Study of Perioperative Cisplatin-Capecitabine Chemotherapy With Preoperative Chemoradiation for Resectable Gastric Cancers

OBJECTIVES

The standard of care for resectable gastric cancers (GCs) includes perioperative chemotherapy (CT) or postoperative chemo/chemoradiotherapy (CRT) strategies. Poor treatment compliance postsurgery suggests that intensified surgical adjuvant treatment is more likely deliverable preceding surgery and, therefore, the safety and efficacy of perioperative cisplatin-capecitabine (CX) with preoperative chemoradiation (preopCRT) were ascertained.

MATERIALS AND METHODS

Between January 2017 and December 2018, 28 potentially resectable locally advanced GC patients were offered neoadjuvant CT-2 cycles of CX at 3-weekly intervals, followed by preopCRT 45 Gy/25 fractions/5 weeks and concurrent capecitabine, followed by surgical resection and 3 adjuvant cycles of CX.

RESULTS

Neoadjuvant CT was commenced in 28 patients (100%), preopCRT in 18 patients (64%), and surgery performed in 13 patients (46%). At each treatment step, decreasing patient numbers were due mainly to disease progression (12 [43%]) or other reasons, including (3 [11%]) from treatment-related toxicity. The R0 resection rate was 92% (12/13); a median of 18 nodes was obtained after D2 nodal clearance in 92% (12/13). There were 20%/4%/4% grade 3/4/5 toxicities. The median radiotherapy dose/duration was 45 Gy/5.4 weeks. Adjuvant CT was started in 11 patients (39%) and the third cycle was received by 7 patients (25%). No tumor (ypT0N0) was noted in 23% of the operated patients (3/13), or 11% of the intention-to-treat population (3/28). The median, 1-year, and 2-year survivals were 12 months, 53%, and 32%, respectively.

CONCLUSIONS

Intensified preoperative treatment is doable in relatively unselected advanced GC patients in real-world settings of a public-sector hospital from a low-middle-income country. Disease progression during preoperative therapy allows patients destined for early clinical evidence of disease dissemination to avoid futile surgery, as opposed to a surgery-first strategy, without an overt increase in surgical morbidity or mortality, with encouraging R0 resection rates.

ICG-NIR-guided lymph node dissection during robotic subtotal gastrectomy for gastric cancer. A single-centre experience

BACKGROUND

Near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) allows intraoperative visualisation of the lymph nodes (LNs) draining the tumour.

METHODS

We included in our study 20 patients who underwent robotic subtotal gastrectomy + D2 lymphadenectomy for gastric cancer. In 10 cases, intraoperative ICG-guided lymphography has been used (Group A). We compared the number of LNs retrieved with the use of NIR imaging and the number of LNs retrieved without the use of this technique (Group B, historical group).

RESULTS

No complications related to ICG injection or near-infrared imaging were observed. The mean number of overall LNs retrieved was significantly greater in Group A than in group B (40 vs. 24). No statistically significant difference in operative time was observed.

CONCLUSIONS

ICG-guided fluorescent lymphography can help in performing a more accurate locoregional lymphadenectomy during robotic subtotal gastrectomy for gastric cancer. This technique represents a precious contribution to gastric cancer surgery.

Decision-making of adjuvant therapy in pT1N1M0 gastric cancer: Should radiotherapy be added to chemotherapy? A propensity score-matched analysis

Background: Early gastric cancer (EGC) with metastatic lymph nodes (mLNs) has a relatively higher recurrence rate and poorer prognosis than EGC without mLNs. However, the postoperative treatment directions of pT1N1M0 vary from different guidelines. This study attempted to confirm the value of postoperative treatments in pT1N1M0 GC patients.

Methods: Overall, 379 patients with pT1N1M0 GC following gastrectomy from 2000 to 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score-matched (PSM) analysis was used to reduce bias. Overall survival was analyzed by Kaplan-Meier method and the log-rank test. Cox proportional hazards regression analyses were used to confirm the independent prognostic factors.

Results: Before matching, the results of survival analyses indicated that adjuvant chemotherapy (ACT) and chemoradiotherapy (ACRT) could significantly prolong the survival time of the cohort (P < 0.05). After PSM analysis, 136 patients remained and ACRT maintained significance in the survival analysis (P = 0.018). Furthermore, patients with well or moderately differentiated GC (HR = 0.226, P =0.018) or intestinal type GC (HR = 0.380, P = 0.040) achieved a significantly superior prognosis with ACRT, compared to patients receiving ACT.

Conclusion: The survival benefit of ACRT and ACT for pT1N1M0 GC patients following gastrectomy was confirmed in the SEER cohort. RT added to ACT might be recommended according to Lauren's classification and tumor grade in clinical decision making.

Patterns of recurrence after curative D2 resection for gastric cancer: Implications for postoperative radiotherapy

BACKGROUND

High-quality randomized controlled trials have demonstrated the benefit of radiotherapy (RT) in patients with radical resected gastric cancer (GC), however, utilization rates of postoperative RT remain remarkably low. Patterns, incidences, and time of recurrence provide biological bases for clinical monitoring of GC patients and guiding potential complementary therapies. Thus, the aim of this study is to understand the location of locoregional recurrence which may allow individualized RT strategies and minimize radiation-related toxic effects.

METHODS

A relatively large sample of GC patients in a single institution who had undergone curative D2 resection was retrospectively reviewed and the relevant recurrence patterns were illustrated. Independent recurrence-related risk factors were analyzed by logistic regression analysis. New logistic regression models were further developed to predict the probability of recurrence.

RESULTS

Overall, among 776 GC patients who had continuous and complete follow-up data, 300 cases relapsed after curative resection. Lymphovascular invasion, lymph node metastases, and tumor stage were indicators for early recurrence. Peritoneal, regional, local, and distant recurrence initially occurred in 51 (6.6%), 151 (19.4%), 56 (7.2%), and 164 (21.1%) patients, respectively. Among patients with regional recurrence, the most common sites were lymph node stations 16a2, 8, 12, 16b1, and 9. Remnant stomach recurrence was not so prominent that it seemed reasonable to be excluded from an irradiation field for patients with negative surgical/pathologic margins.

CONCLUSIONS

For GC patients who underwent radical D2 resection, distant and regional recurrences were still common. Besides, optimizing regional control of lymph nodes outside the D2 dissected area was crucial for rational design of the RT field. Furthermore, the new logistic regression models might act as useful tools to evaluate recurrence risk and determine which patients should receive postoperative chemoradiotherapy.