Histological characterisation and prognostic evaluation of 62 gastric neuroendocrine carcinomas

Equivalent Survival between Gastric Large-Cell Neuroendocrine Carcinoma and Gastric Small-Cell Neuroendocrine Carcinoma

BACKGROUND

According to the 2019 World Health Organization (WHO) classification of gastric neuroendocrine neoplasms, gastric neuroendocrine carcinoma (GNEC) can be further divided into gastric large-cell neuroendocrine carcinoma (GLNEC) and gastric small-cell neuroendocrine carcinoma (GSNEC). Whether the prognoses of the two types have a discrepancy has long been disputed.

METHOD

We collected patients diagnosed with GLNEC or GSNEC in the National Cancer Center of China between January 2000 and December 2020. The characteristics and survival outcomes were compared between the two groups. We further verified our conclusion using the SEER dataset.

RESULTS

A total of 114 GNEC patients, including 82 patients with GLNEC and 32 patients with GSNEC, have completed treatment in our hospital. Clinicopathologic differences were not observed between patients with GSNEC and GLNEC concerning the sex, age, body mass index, Charlson Comorbidity Index, tumor location, tumor size, stage, treatment received, the expression of neuroendocrine markers (CD56, Chromogranin A, synaptophysin), and score on the Ki-67 index. The 1-year, 3-year, and 5-year overall survival rates of GLNEC and GSNEC were 89.0%, 60.5%, and 52.4%, and 93.8%, 56.3%, and 52.7%, which showed no statistically significant differences. This result was confirmed further by using the SEER dataset after the inverse probability of treatment weighting.

CONCLUSIONS

Although with different cell morphology, the comparison of prognosis between the GLNEC and GSNEC has no significant statistical difference.

Treatment strategies for neuroendocrine carcinoma of the upper digestive tract

BACKGROUND

Neuroendocrine carcinoma (NEC) of the esophagus and the stomach is aggressive. The purpose of this study was to determine the optimal therapeutic strategy.

METHODS

Both clinicopathological factors and treatment results were examined in 34 patients with immunohistochemically diagnosed NEC of the upper gastrointestinal tract (esophagus 22; stomach 12).

RESULTS

Twenty-nine tumors showed protruding and localized type, like submucosal tumor. Esophagectomy and gastrectomy were performed in six and eight patients, respectively. Among the six patients with esophageal NEC, three with node metastasis developed recurrence within seven months, while the other three (pT1bN0) had no recurrence. Regarding gastric NEC, three patients with pT3N1 or 2 tumor received adjuvant chemotherapy and achieved a 5-year survival. However, the other five experienced recurrence after gastrectomy. Systemic chemotherapy was performed as the main treatment for 18 patients with advanced NEC. The median survival was 10 months after initial chemotherapy. No marked differences in the response were recognized between the 14 cases with esophageal NEC and the 4 with gastric NEC. The median survival was 14.3 and 5.3 months for the 11 effective and 7 non-effective patients, respectively.

CONCLUSIONS

A macroscopically unique appearance, like submucosal tumor, suggests the possibility of NEC. Esophagectomy is an effective treatment option for limited-stage NEC without node metastasis, while gastrectomy followed by adjuvant chemotherapy may be effective for NEC even with node metastasis when R0 resection can be achieved. Systemic chemotherapy is relatively effective for advanced NEC, although early progression frequently develops.

P53, Somatostatin receptor 2a and Chromogranin A immunostaining as prognostic markers in high grade gastroenteropancreatic neuroendocrine neoplasms

Background

High grade gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) with a Ki67 proliferation index > 20%, include well-differentiated tumours grade 3 (NET G3) and poorly differentiated (PD) neuroendocrine carcinomas (NEC). Abnormal p53-expression is a feature of PD tumours, while expression of chromogranin A (CgA) and somatostatin-receptor 2a (SSTR-2a) may be a feature of well-differentiated tumours. The aim of this study was to elucidate the expression and prognostic value of these three markers in 163 GEP-NEN patients with a Ki67-index > 20%.

Method

Clinical data, histopathology and overall survival were analysed according to Kaplan-Meier’s method and Cox regression. The expression of SSTR-2a, CgA and synaptophysin was analysed in tumour specimens by immunohistochemistry, and semi-quantitatively scored as negative (< 5%), heterogeneously positive (5–30%) or strongly positive (> 30%). P53 was defined as normal when scored as heterogeneously positive (1–30%), and abnormal when negative (0%) or strongly positive (> 30%).

Results

In multivariate analysis, better survival was observed among patients with heterogeneously positive p53 compared to strongly positive (p < 0.001). When dichotomised, tumours with a heterogeneously positive p53 vs. negative and strongly positive p53 also showed a significantly better survival (p = 0.002).

Survival was significantly worse for negative CgA compared to heterogeneously positive CgA (p = 0.02). Strongly positive SSTR-2a expression was found in 26% of the 163 included patients. Well-differentiated morphology correlated with strong expression of SSTR-2a and CgA, and heterogeneously positive p53-staining, and was more frequent in pancreatic primaries. In pancreatic primaries, strongly positive SSTR-2a was associated with longer survival (univariate analysis, p = 0.02). A significantly lower Ki67 proliferation index was found in patients with a heterogeneously positive p53, a positive SSTR-2a and CgA expression.

Conclusion

Our results suggest that abnormal p53-expression is an independent negative prognostic marker in GEP-NEN with a Ki67-index > 20%. Patients with heterogeneously positive p53 had the best prognosis. SSTR-2a was a positive prognostic marker in pancreatic NEN. Negative CgA was associated with a significantly worse OS compared to heterogeneously positive CgA-expression in a multivariate sub-analysis. Lower Ki67 index correlated significantly with heterogeneously positive p53, positive SSTR-2a and CgA expression.

Loss of expression rather than cytoplasmic mislocalization of RUNX3 predicts worse outcome in non-small cell lung cancer

Functional inactivation of human runt-related transcription factor 3 (RUNX3) through mutation or epigenetic silencing has been well-documented in many cancerous entities. In addition to gene mutation and promoter hypermethylation, cytoplasmic mislocalization has emerged as another major manifestation of RUNX3 dysfunction in malignancies including breast, colorectal and gastric cancers. The aim of the present study was to investigate whether patients with non-small cell lung cancer (NSCLC) and different RUNX3 expression patterns would have different overall survival (OS), and the associations between different patterns of clinicopathological parameters and clinical outcome. Expressions of RUNX3 and Ki-67 were immunohistochemically detected in normal lung tissue (n=5) and surgically resected tissues from NSCLC patients (n=188). The optimal cutoff of RUNX3 was determined by X-tile software associated with their survival. Apoptotic index in cancerous tissue was evaluated using the terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labelling method. The prognostic significance of different expression patterns of RUNX3 was determined by means of Kaplan-Meier survival estimates and log-rank tests. It was revealed that loss of RUNX3 expression in NSCLC was correlated with a low cancerous apoptotic index (P<0.001), shorter OS and worse prognosis (P=0.0142), while no statistical difference of apoptotic index (P=0.73) or survival (P=0.3781) was determined between patient subgroups with different localization of RUNX3 expression, which was quite different from the situation demonstrated in other malignancies. In conclusion, loss of expression rather than cytoplasmic mislocalization of RUNX3 predicted worse outcome in NSCLC, which was quite different from what manifested in other cancer types, and thus, the underlying mechanism may deserve further investigation.

Clinicopathological and prognostic significance of Ki-67 immunohistochemical expression in gastric cancer: a systematic review and meta-analysis

The prognostic significance of Ki-67 in patients with gastric cancer (GC) remains controversial. The aim of our meta-analysis is to evaluate its association with clinicopathological characteristics and prognostic value in patients with GC. PubMed, EMBASE, and Web of Science were systematically searched up to May 2017. Twenty-two studies including 3,825 patients with GC were analyzed. The meta-analysis indicated that the incidence difference of Ki-67 expression in GC patients was significant when comparing the older group to younger group (odds ratio [OR] =1.44, 95% confidence interval [CI] 1.19, 1.75), lymph node positive group to negative group (OR =1.49, 95% CI 1.20, 1.84), the large size tumor group to the small size tumor group (OR =1.27, 95% CI 1.24, 1.68) and the TNM stage III+IV group to TNM stage I+II group (OR =2.28, 95% CI 1.66, 3.12). However, no statistical differences existed in gender. The detection of Ki-67 significantly correlated with the overall survival of patients (hazard ratio =1.51, 95% CI 1.31, 1.72). Our study suggested that Ki-67 overexpression was associated with poor prognosis in GC patients. Ki-67 positive rates may be associated with age, lymph node metastasis, tumor size, and TNM staging system in GC patients.

MECP2 expression in gastric cancer and its correlation with clinical pathological parameters

This study is to investigate the expression of methyl CpG binding protein 2 (MECP2) in gastric cancer (GC) and its clinical significance.Expression of MECP2 was analyzed in 69 cases of GC tissues and 12 paracancerous tissues, either by qRT-PCR at the mRNA level or by Western blot and immunochemistry at the protein level. The correlation of MECP2 expression with clinicopathological parameters was analyzed in the 69 GC patients, and validated in data from the TCGA database. The effect of MECP2 expression on survival was also investigated.MECP2 was significantly increased at both mRNA and protein levels in GC compared with paracancerous tissues. MECP2 positive expression was significantly correlated with the TNM stages, histological types, and lymph node metastasis status, but was not correlated with sex or age. Significantly shorter overall survival and disease-free survival was observed in MECP2 positive GC cases compared with the MECP2 negative cases. Univariate and multivariate analyses showed that gender, histological type, lymph node metastasis, and MECP2 expression were independent prognostic factors of GC.The dysregulated expression of MECP2 in GC and its correlation to clinicopathological parameters indicate that MECP2 may regulate the development of GC.