Survival after Gastrectomy in Node-Negative Gastric Cancer: A Review and Meta-Analysis of Prognostic Factors

The Association Between Neoadjuvant Therapy and Pathological Outcomes in Pancreatic Cancer Patients After Resection: Prognostic Significance of Microscopic Venous Invasion

BACKGROUND

The impact of neoadjuvant therapy (NAT) on pathological outcomes, including microscopic venous invasion (MVI), remains unclear in pancreatic cancer.

METHODS

A total of 456 patients who underwent pancreatectomy for resectable and borderline resectable pancreatic cancer between July 2012 and February 2020 were retrospectively reviewed. Patients were divided into two groups: patients with NAT (n = 120, 26%) and those without NAT (n = 336, 74%). Clinicopathological factors, survival outcomes and recurrence patterns were analyzed.

RESULTS

Regarding pathological findings, the proportion of MVI was significantly lower in patients with NAT than in those without NAT (43% vs 62%, P = 0.001). The 5-year survival rate in patients with NAT was significantly better than that in those without NAT (54% vs 45%, P = 0.030). A multivariate analysis showed that MVI was an independent prognostic factor for the overall survival (OS) (hazard ratio 2.86, P = 0.003) in patients who underwent NAT. MVI was an independent risk factor for liver recurrence (odds ratio [OR] 2.38, P = 0.016) and multiple-site recurrence (OR 1.92, P = 0.027) according to a multivariate analysis. The OS in patients with liver recurrence was significantly worse than that in patients with other recurrence patterns (vs lymph node, P = 0.047; vs local, P < 0.001; vs lung, P < 0.001). The absence of NAT was a significant risk factor for MVI (OR 1.93, P = 0.007).

CONCLUSION

MVI was a crucial prognostic factor associated with liver and multiple-site recurrence in pancreatic cancer patients with NAT. MVI may be reduced by NAT, which may contribute to the improvement of survival in pancreatic cancer patients.

Misclassification of nodal stage in gastric cancer: 16 lymph nodes is not enough

Background

In gastric cancer, nodal stage plays an important role. Insufficient lymph node harvesting or incomplete examination may lead to misclassification and affect postoperative strategy and group survival. This study’s objective was to determine the minimum number of examined lymph nodes needed in gastric cancer and compare this to the minimum lymph node count according to the current Union for International Cancer Control (UICC) classification using real world data.

Methods

Based on anatomical data, expected mean lymph node counts and their 95% confidence intervals for complete D2 lymphadenectomy were calculated. Using stochastic analysis, a threshold for correct classification in 95% of cases was determined. Survival data of nodal negative gastric cancer patients was extracted from the Surveillance, Epidemiology, and End Results (SEER)-Database for 2010–2017. Patients reaching at least the calculated theoretical threshold were compared to the minimum threshold according to the current UICC classification.

Results

The expected lymph node count was 30 (95% CI: 28–32; range 17–52), corresponding to a 27 lymph nodes. In nodal negative patients with exactly 16 and at least 27 examined lymph nodes, relative 5 year survival was 79 and 89% in T1/T2 and 39 and 64% T3/T4 gastric cancer, respectively. Theoretically, when only 16 lymph nodes are analyzed, nodal negative staging may be incorrect in up to 47% of cases.

Conclusions

A minimum threshold of 16 examined lymph nodes cannot be justified. Retrospective analysis confirmed systematic misclassification of patients with insufficient lymphadenectomy in nodal negative gastric cancer patients. Correct lymphadenectomy and thorough examination of the surgical specimen is mandatory.

Determinants of Survival for Patients with Neoadjuvant-Treated Node-Negative Gastric Cancer

BACKGROUND

This study sought to determine prognostic markers for disease recurrence and survival in a cohort of neoadjuvant-treated, node-negative gastric cancer patients (ypT0-4N0M0).

METHODS

Clinicopathologic data from patients treated with neoadjuvant therapy followed by curative-intent gastrectomy at the University of Texas MD Anderson Cancer Center from 1995 to 2017 were evaluated. Patients with AJCC TNM stage ypT0-4N0M0 were considered for analysis.

RESULTS

The inclusion criteria were met by 212 patients with a mean age of 58.3 years. Of these patients, 60 % were male, 53 % were Caucasian, 87 % received chemoradiation, and 13 % received chemotherapy. The findings showed a median overall survival (OS) rate of 11.3 years, a 5-year survival rate of 72 %, and a 10-year survival rate of 57 %. During a median follow-up period of 5.5 years, 38.2 % of the patients died. In the multivariable analysis, ypT4-stage and nodal yield fewer than 16 were significantly associated with reduced OS. Cancer classified as ypT4 had more aggressive biologic traits, including lymphovascular and perineural invasion, and was treated more aggressively with total gastrectomy and additional organ resection despite frequent positive margins. Depth of invasion remained significantly associated with worse outcome after the analysis controlled for nodal yield and possible stage migration. Compared with ypT0-3 tumors, ypT4 cancers were associated with significantly more recurrences (13 % vs. 45 %; p < 0.05), and the primary modes of failure for ypT4 lesions were local recurrence and peritoneal metastases (88 % of recurrences).

CONCLUSIONS

Depth of primary tumor invasion and nodal yield were significantly associated with OS among the patients with ypT0-4N0M0 gastric cancer. Serosal invasion (ypT4) was associated with a high rate of peritoneal recurrence, and trials of intraperitoneal therapy targeting these patients should be considered.

Role of Conversion Surgery for Unresectable Pancreatic Cancer After Long-Term Chemotherapy

BACKGROUND

Unresectable pancreatic cancer (UR-PC) has a poor prognosis. Although conversion surgery has been considered a promising strategy for improving prognosis in UR-PC, the clinical benefit offered to patients with UR-PC remains controversial. This study aimed to investigate the clinical benefits of conversion surgery in patients with UR-PC.

METHODS

We evaluated patients with UR-PC referred to our department for possible surgical resection between January 2008 and June 2017. Resectability was evaluated using multimodal imaging in patients who underwent chemotherapy for more than 6 months. Conversion surgery was performed only in patients who were judged eligible for R0 resection.

RESULTS

In total, 90 patients were evaluated. Among them, only 22 (24.4%) could actually undergo conversion surgery, and the R0 resection rate was 72.7% (16/22). Although Evans grade ≥ IIB was noted in six patients (27.3%), none achieved complete response (CR). The median survival time was significantly longer among patients who underwent conversion surgery than in the unresected patients who underwent chemotherapy (21.3 months vs. 12.6 months; p < 0.001). Multivariate and Kaplan-Meier analyses revealed microvascular invasion to have a significant adverse effect on recurrence-free survival (RFS: 7 months vs. not reached, p = 0.004) and overall survival (OS: 21 months vs. 85 months, p = 0.047).

CONCLUSIONS

After long-term chemotherapy, conversion surgery for UR-PC is associated with long-term survival. Microvascular invasion is predictive of poor prognosis in these patients; adjuvant protocols are therefore needed for patients with microvascular invasion.

Prognostic Models for Predicting Overall Survival in Patients with Primary Gastric Cancer: A Systematic Review

Background

This study was designed to review the methodology and reporting of gastric cancer prognostic models and identify potential problems in model development.

Methods

This systematic review was conducted following the CHARMS checklist. MEDLINE and EMBASE were searched. Information on patient characteristics, methodological details, and models' performance was extracted. Descriptive statistics was used to summarize the methodological and reporting quality.

Results

In total, 101 model developments and 32 external validations were included. The median (range) of training sample size, number of death, and number of final predictors were 360 (29 to 15320), 193 (14 to 9560), and 5 (2 to 53), respectively. Ninety-one models were developed from routine clinical data. Statistical assumptions were reported to be checked in only nine models. Most model developments (94/101) used complete-case analysis. Discrimination and calibration were not reported in 33 and 55 models, respectively. The majority of models (81/101) have never been externally validated. None of the models have been evaluated regarding clinical impact.

Conclusions

Many prognostic models have been developed, but their usefulness in clinical practice remains uncertain due to methodological shortcomings, insufficient reporting, and lack of external validation and impact studies.

Impact

Future research should improve methodological and reporting quality and emphasize more on external validation and impact assessment.

Implications of clinical research on adjuvant chemotherapy for gastric cancer: Where to go next?

Postoperative adjuvant chemotherapy (ACT) confers superior gastric cancer (GC) survival in the Eastern cohort. However, is the current standard of ACT already excessive, or is it still necessary to increase its intensity for specific subgroups? Tailored ACT strategies for GC depend on gradual exploration by clinical trials in selected patients. Thus, understanding the implications of previous and current research can help us respond wisely and design effective, rational trials, save medical resources and make better decisions in clinical practice. After reviewing and analyzing studies on ACT for GC patients undergoing curative resection, we found that research strategies for conducting “addition” ACT for specific stages of the disease have achieved great progress in making ACT more tailored and personalized in consideration of pathology stages. Furthermore, trials indicate that “addition” ACT strategies for GC patient subgroups based on histological characteristics might be helpful to move toward a more specific tailored and personalized management approach. Designing ACT research focused on different node statuses should also be conducted according to the biological specificity of lymph node (LN) metastasis. Therefore, future trials designed to determine tailored treatment based on histological and biological characteristics for specific subgroups are urgently needed and conducted as the theme of the 2019 American Society of Clinical Oncology (ASCO): Caring for Every Patient, Learning from Every Patient.

Adjuvant Therapy is Associated with Improved Survival in pT1N1 Gastric Cancer in a Heterogeneous Western Patient Population

BACKGROUND

Two recent South Korean studies showed adjuvant therapy (AT) was not associated with improved survival in pT1N1 gastric adenocarcinoma (GAC). We established the prognostic utility of lymph node status, determined the pattern of use of AT, and compared survival stratified by type of AT in pT1N1 GAC in a Western patient population.

METHODS

We identified patients with pT1N0 and pT1N1 GAC using the National Cancer Database from 2004 to 2012. Clinicopathologic variables, treatment regimens, and overall survival (OS) were compared.

RESULTS

We compared 4516 (86.6%) pT1N0 to 696 (13.4%) pT1N1 patients. pT1N1 tumors were larger (median size 2.5 vs. 1.8 cm, p < 0.001), more often poorly differentiated (56.2% vs. 39.6%, p < 0.001), and had higher median retrieved lymph nodes (RLN) (14 vs. 12, p < 0.001) compared with pT1N0. pT1N1 was associated with worse median overall survival (OS) (6.9 vs. 9.9 years for pT1N0, p < 0.001). pN1 was independently associated with worse OS (hazard ratio [HR] 2.17, 95% confidence interval [CI] 1.84-2.56). Increased RLN was associated with improved OS (HR 0.73, 95% CI 0.65-0.83). Among pT1N1 patients, 330 (47.4%) had observation (OBS), 77 (11.1%) received adjuvant chemotherapy (ACT), 68 (9.8%) received adjuvant radiation therapy (ART), and 221 (31.8%) received adjuvant chemoradiation therapy (ACRT). ACT and ACRT were independently associated with improved OS (HR 0.37, 95% CI 0.22-0.65 and HR 0.40, 95% CI 0.28-0.57).

CONCLUSIONS

pN1 was associated with worse survival and RLN ≥ 15 was associated with improved survival in pT1 GAC. ACT and ACRT were independently associated with improved survival in pT1N1 gastric cancer suggesting a valuable role in Western patients.

Expression of gremlin1 in gastric cancer and its clinical significance

As an antagonist of bone morphogenetic proteins (BMPs), 2, 4 and 7, gremlin1 plays a role in regulating organogenesis, tissue differentiation and angiogenesis. However, there is little information regarding gremlin1 in gastrointestinal cancer. We attempted to clarify how gremlin1 expression affects the clinical features and biological properties of gastric cancer. A total of 232 gastric cancer patients who received R0 gastrectomy at Kagoshima University Hospital were enrolled. Gremlin1 expression in gastric cancer was detected by immunohistochemical and western blotting methods. Correlations between clinicopathological parameters and gremlin1 expression were analyzed. Gremlin1 was identified in the cytoplasm and nucleus of all gastric cancer cell lines and some regions of surgical specimens of gastric cancer. One hundred and seventeen of the 232 patients (50.4%) were classified as gremlin1-positive based on gremlin1 expression. Gremlin1 positivity was correlated with shallower tumor depth, smaller tumor size, less nodal involvement and vessel invasion (p < 0.05). The 5-year survival rate of the gremlin1-positive group was 81%, which was significantly higher than the gremlin1-negative group (p < 0.01). Multivariate analysis revealed that gremlin1 was not selected as an independent prognostic marker. Gremlin1 expression in gastric cancer may be a useful prognostic marker that is involved with the BMP signaling pathway. Furthermore, gremlin1 may have clinical use as a diagnostic and treatment tool.

Microscopic Venous Invasion in Pancreatic Cancer

BACKGROUND

Microscopic venous invasion (MVI) and the subsequent peripheral blood circulation of cancer cells are considered to be the primary route for systemic dissemination of pancreatic cancer.

METHODS

Patients who underwent pancreatectomy for invasive ductal carcinoma of the pancreas between January 2007 and December 2015 were retrospectively reviewed. The prognostic significance of MVI was analyzed.

RESULTS

A total of 352 patients underwent pancreatectomy for invasive ductal carcinoma of the pancreas. A pathologic examination showed MVI in 228 (64.5%) of the patients. The median survival time (MST) was 21 months for the patients with MVI and 58 months for those without MVI (p < 0.001). A multivariate analysis showed the following to be significant prognostic factors: non-administration of adjuvant chemotherapy [hazard ratio (HR) 2.37; p < 0.001], lymph node metastasis (HR 2.95; p = 0.001), CA19-9 value of 300 U/ml or higher (HR 1.70; p = 0.018), and MVI (HR 1.84; p = 0.011). The overall survival was clearly stratified into three groups; favorable (MST not reached in stage 1 or 2A without MVI; p = 0.867), moderate (30 months in stage 2A with MVI and 30 months in stage 2B without MVI; p = 0.528), and poor (19 months in stage 2B with MVI and 17 months in stage 4; p = 0.322). The differences between these three groups all were significant.

CONCLUSIONS

Approximately two-thirds of patients with radiologically resectable pancreatic cancer had MVI and were considered to have potentially systemic disease. This study identified MVI as one of the significant factors for a poor prognosis and a valuable complement of tumor-node-metastasis staging.

Current status of lymph node micrometastasis in gastric cancer

Lymph node metastasis is one of the most important prognostic factors in patients with gastric cancer. An inadequate number of dissected lymph nodes is an independent risk factor affecting recurrence, even in patients who are node negative. Oddly, certain early-stage patients still experience recurrence or metastasis within a short time, even if they have undergone standard radical mastectomy. Many researchers have attributed these adverse events to lymph node micrometastasis (LNM), which is defined as a microscopic deposit of malignant cells of less than 2 mm in diameter. With the development of diagnostic tools such as immunohistochemistry and reverse transcription-polymerase chain reaction, the rate of detection of LNM has been constantly increasing. Although there is no clear consensus about risk factors for or the definitive clinical significance of LNM, the clinical impact of LNM is remarkable in gastric cancer. For minimally invasive treatment in particular, such as endoscopic submucosal dissection and laparoscopic surgery, accurate diagnosis of LNM is regarded as the potential key to maintaining the balance between curability and safety. This review provides an overview of the definition, detection and significance of LNM in gastric cancer. We also summarize several attention-drawing controversies regarding the treatment of patients who may have LNM.

An update on the strategies used for the treatment of chronic hepatitis B in children

Chronic hepatitis B (CHB) in children shows a variety of clinical presentations, which influence its natural course and treatment options. This report provides an overview of the ongoing strategies in pediatric CHB management. Interferon-α represents the first choice of treatment in children showing HBV replication and hepatic inflammation (immune active CHB), while the recommendation is to monitor inactive/immune-tolerant children (normal transaminases and low/absent viral replication). When circumstances preclude the use of Interferon-α and in cases of compensated/decompensated cirrhosis, entecavir for children above 2 years of age or tenofovir for children above 12 years of age are the nucleos(t)ide analogues recommended by the most recent guidelines.