The Correlation of Ten Immune Checkpoint Gene Expressions and Their Association with Gastric Cancer Development

In the immunotherapy based on immune checkpoint inhibition (IC), additional ICs are being studied to increase its effectiveness. An almost unstudied feature is the possible co-expression of ICs, which can determine the therapeutic efficacy of their inhibition. For the selection of promising ICs, information on the association of their expression with cancer development may be essential. We have obtained data on the expression correlation of ADAM17, PVR, TDO2, CD274, CD276, CEACAM1, IDO1, LGALS3, LGALS9, and HHLA2 genes in gastric cancer (GC). All but one, TDO2, have other IC genes with co-expression at some stage. At the metastatic stage, the expression of the IDO1 does not correlate with any other gene. The correlations are positive, but the expressions of the CD276 and CEACAM1 genes are negatively correlated. The expression of TDO2 and LGALS3 is associated with GC metastasis. The expression of TDO2 four-fold higher in metastatic tumors than in non-metastatic tumors, but LGALS3 was two-fold lower. The differentiation is associated with IDO1. The revealed features of TDO2, with a significant increase in expression at the metastatic stage and the absence of other IC genes with correlated expression indicates that the prospect of inhibiting TDO2 in metastatic GC. IDO1 may be considered for inhibition in low-differentiated tumors.

Clinical significance of molecular subtypes of gastrointestinal tract adenocarcinoma

Adenocarcinomas of the gastrointestinal tract (esophagus, stomach, and colon) represent a heterogeneous group of diseases with distinct etiology, clinical features, treatment approaches, and prognosis. Studies are ongoing to isolate molecular genetic subtypes, perform complete biological characterization of the tumor, determine prognostic groups, and find predictive markers to the effectiveness of therapy. Separate molecular genetic classifications were created for esophageal adenocarcinoma [The Cancer Genome Atlas (TCGA)], stomach cancer (TCGA, Asian Cancer Research Group), and colon cancer (Colorectal Cancer Subtyping Consortium). In 2018, isolation of TCGA molecular genetic subtypes for adenocarcinomas of the gastrointestinal tract (esophagus, stomach, and colon) highlighted the need for further studies and clinical validation of subtyping of gastrointestinal adenocarcinomas. However, this approach has limitations. The aim of our work was to critically analyze integration of molecular genetic subtyping of gastrointestinal adenocarcinomas in clinical practice.

A prospective study of prognostic role of plasma circulating tumor DNA (ctDNA) in patients (pts) with early-stage malignancies

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Background: Recently, conflicting evidence has emerged showing the association of ctDNA level and cancer progression. The aim of our study was the development of a method for detecting ctDNA in plasma and the investigation of the prognostic value of ctDNA retention after surgery in the prospective way. Methods: This prospective, single-center, sample collection study; pts with early-stage malignancies of the different origin were included. Tumor somatic mutations were determined by target sequencing of DNA from FFPE tumor blocks. Sequencing was performed using the custom NGS panel covering regions of frequent somatic mutations in 50 genes. Tumor-specific mutations were monitored in plasma samples taken before and after surgery. The median time between surgery and plasma collection was 7 days (5-15). Mutations of plasma ctDNA were determined by ddPCR. The plasma sample was considered "positive" if the content of ctDNA was more than 0.5 copies of mutant DNA in ml plasma. We needed 265 pts for improving 1-year disease free survival (DFS) from 60% to 80% with α=0.01, β=0.1, 10% loss of f.-up and duration of the study for 2 years. Results: The study comprised 271 pts with various cancers including colorectal – 91 (33,6%), pancreatic – 37 (13,7%), breast – 66 (24,4%), lung – 35 (12,9%) and gastric cancer – 42 (15,5%). Pts with stage I was 50 (18,5%), stage II – 118 (43,5%) and stage III – 103 (38%). The median time of the f.-up was 9 mos. (1-37). No significant association was found between the level of ctDNA before surgery and DFS either in the general group or in groups stratified by tumor sites (HR 2.4, 95%CI 0.8-7.1, р=0.12 and HR 1.5, 95%CI 0.4-6.3, р=0.5, correspondingly). ctDNA was detected in the plasma after surgery in 57 (10%) pts: 9 (9.9%) cases of colorectal, 10 (27%) - pancreatic, 9 (13.6%) - breast, 19 (54.3%) - lung, and 10 (23.8%) - gastric cancer. Progression of the disease was detected in 28/57 (49%) pts with ctDNA(+) and 17/214 (8%) - in ctDNA(-) pts (p<0.001). One-year DFS in ctDNA(+) and ctDNA(-) pts were 57% and 87%, respectively (HR 6.1, 95%CI 3.3-11.2, p<0,001). ctDNA positivity after surgery was an independent negative prognostic factor according to Cox regression model fitted to T, N, and adjuvant chemotherapy (HR 5.7, 95%CI 3.1-10.8, p <0.001). Conclusions: These results demonstrate the prognostic significance of ctDNA persisting after surgery in pts with the early stage of the different malignancies. Further clinical validation of this approach is required in trails with modifications of the adjuvant treatment, according to the content of ctDNA.

The real-world practiсe of surgery in patients with metastatic gastric cancer (mGC)

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Background: According to recent studies the results of treatment patients with initially mGC are still not sufficient: median overall survival varies between 6.1 and 12.4 months. The triplet-chemotherapy regimens demonstrate high efficacy and allow to downstage the disease and perform surgical treatment. Conversion treatment in stage IV GC is a modern trend and still an area of ongoing research. Methods: We analyzed the efficacy of first line chemotherapy (6-9 courses) for patients with mGC (n = 55) including the following regimens: 1) mFOLFIRINOX; 2) douplet: oxaliplatin/irinotecan + fluoropyrimidine; 3) triplet variations: docetaxel, platinum and fluoropyrimidine. 27/55 patients had > 2 metastatic sites, 2/55 patient - 5 metastatic sites. The most common localizations of metastases were peritoneum (n = 34) and retroperitoneal lymph nodes (n = 11). Unlike in REGATTA trial all patients underwent surgical treatment with curative intent followed by complete response of distant metastases after chemotherapy. For patients with ovarian metastases ovariectomy was also perfomed. Results: Median progression-free survival and median overall survival were 18.5 and 33.27 months, respectively and the 3-year survival rate was 43.5%. Multivariate analysis showed that clinically determined ascites (p = 0.023), linitis plastica (p = 0.022), tumor grade 3 (p = 0.014), present of lymphovascular invasion (p = 0.037), absence of grade III-IV pathomorphosis (p = 0.037) and treatment free interval before surgery < 3.4 month (p = 0.046) were poor independent prognostic factors. Conclusions: Surgery after effective combination chemotherapy may have significant clinical efficacy for selected patients with initially unresectable gastric cancer. According to our data the optimal time for surgery is a 3.4 and more months treatment-free interval in the absence of disease progression.

Preoperative chemotherapy in patients with resectable esophageal carcinoma: a single center Phase II study

OBJECTIVE

The role of preoperative chemotherapy in squamous cell esophageal carcinoma remains controversial. A prospective trial was initiated to investigate whether preoperative chemotherapy followed by surgery results in increased progression-free survival in patients with resectable thoracic esophageal carcinoma.

METHODS

Patients with Stage IIb-IIIa/b resectable esophageal carcinoma were eligible for the study. They received two cycles of FLEP regimen chemotherapy (cisplatin, etoposide, leucovorine, 5-fluorouracil) followed by transthoracic extended 2- or 3-field esophagectomy. Two-year progression-free survival was the primary endpoint. To evaluate the potential benefit of the dual-modality approach we compared these results with the outcome of patients who were treated in our center in the same period of time and were non-randomly allocated to surgery alone.

RESULTS

From 2001 to 2008, 63 patients were included in the study (bimodality group) and 58 patients into the surgery-alone group. Median follow-up was 68 (range, 4-123) months. Squamous cell carcinoma had 93% patients. Two-year progression-free survival for all patients was 45.3 and 30.7% (hazard ratio 0.71, 95% confidence interval 0.46-1.08) and median overall survival was 26.5 months and 18.0 months (hazard ratio 0.67, 95% confidence interval 0.41-1.01) in bimodality- and surgery-alone groups, respectively. Patients who underwent R0-resection after bimodality treatment had significantly better overall survival (40.9 months) than after surgery alone (19.0 months, hazard ratio 0.51, 95% confidence interval 0.30-0.81).

CONCLUSIONS

Two cycles of preoperative chemotherapy did not improve progression-free survival of patients with resectable thoracic esophageal carcinoma in intent-to-treat population. However, significantly better results of bimodality approach was seen in R0-resected patients which warrants further trials with more effective chemotherapy combinations.

Preoperative chemotherapy followed by resection vs. surgery alone for locally advanced esophageal carcinoma: Interim analysis of a randomized study

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Background: Outcome of the patients (pts) with locally advanced esophageal cancer is poor. A prospective trial was undertaken to investigate whether preoperative chemotherapy (CT) followed by surgery results in increase of disease free survival (DFS) in pts with locally advanced resectable thoracic esophageal cancer. Methods: Previously untreated pts with stage T3–4N0–1M0, T1–2N1M0 resectable esophageal cancer were eligible for the study. After clinical evaluation (incl. chest CT-scan, endosonography) they were randomized into CT (two cycles of FLEP: cisplatin 80 mg/m2, day 1; etoposide 80 mg/m2 d 1–3, leucovorine 20 mg/m2 and 5-fluorouracil 425 mg/m2, bolus, days 1–3; every 21 days) followed by surgical resection (Ch-S group), or resection alone (S group). Four weeks after completion of CT pts underwent transthoracic extended 2 or 3-field esophagectomy with intrapleural esophago-gastrostomy through I. Lewis approach. Results: From March 2001 to September 2005 78 pts (Ch-S group, n=38; S group, n=40) were treated in our center. Median f.-up for survived pts was 20 (range, 3–53) months. All pts but one had squamous cell carcinoma. Pts’ characteristics (tumor stage and histology, coexisting disorders, age and gender) were well balanced between the two treatment groups. Main toxicity of CT was hematological, with neutropenia gr. 4 was observed in 7 (18%) pts. There was no other serious toxicity as well as preoperative toxic deaths. Complete response was observed in 3 (7,9%) pts, partial response in 23 (60,5%) pts, progression of disease in 3 (7,9%) pts of Ch-S group. Rate of R0 resection was higher in Ch-S group (86,8%) compared with S group (65%, p=0,03). There was no difference in postoperative mortality between both groups. 3-year DFS was 58,3% vs. 27,7% (p=0,01) and 3-year overall survival was 62,9% vs. 39,8% (p=0,08) in Ch-S and S groups, respectively. Conclusions: Two cycles of preoperative CT improve DFS in pts with resectable locally advanced thoracic esophageal cancer. Accrual is continuing.

No significant financial relationships to disclose.

Subtotal esophagectomy with extended 2-field lymph node dissection for thoracic esophageal cancer

OBJECTIVE

To examine the efficacy of the Ivor Lewis esophagectomy with extended 2-field lymph node dissection for thoracic esophageal carcinoma we reviewed our experience.

METHODS

We analyzed the cases of 147 consecutive patients who underwent subtotal esophagectomy with extended 2-field lymph node dissection through Ivor Lewis approach for esophageal cancer from January 1996 through December 2000. Eighty-six patients were operated on for cancer of the midthoracic esophagus, 48 for cancer of the lower thoracic esophagus, and 13 for cancer of the aortal segment of the esophagus. No patient had received chemotherapy or radiotherapy before operation.

RESULTS

There were 113 men (76.9%) and 34 women. Median age was 57 years (range 51-65 years). Postsurgical pathological studies revealed squamous cell carcinoma in 139 patients (94.6%), adenocarcinoma in five (3.4%), and adenosquamous carcinoma in three (2%). Positive abdominal and/or mediastinal lymph nodes were found in 122 patients (82.9%). At mean 43 nodes (range from 32 up to 75) were studied for each patient. Even in T(1)-T(2) tumors mediastinal or abdominal lymph nodes are involved in up to 80% of cases. However, in T(3)-T(4) stages the frequency of lymph node involvement is significantly higher (P<0.05). Postsurgical staging was as follows: stage I in three patients (2%), stage IIa in 20 (13.6%), stage IIb in 29 (19.7%), stage III in 54 (36.8%), and stage IV in 41 (27.9%). All distant metastases were lymphogenous. The operative mortality rate was 6.1%, and complications occurred in 62 patients (42.1%). The overall 5-year survive rate was 28.8% (median survival 36.1 months). The 5-year survival rate for patients in stage IIa was 59%; for those in stage IIb, 39.5%; for patients in stage III, 26.7%; and 0% for patients in stage IV.

CONCLUSIONS

Subtotal esophagectomy with extended 2-field lymph node dissection through Ivor Lewis approach for esophageal cancer is a safe operation. Long-term survival is stage dependent. Effective multimodality treatment may be helpful for patients with advanced disease.

Surgical treatment of esophageal carcinoma complicated by fistulas

OBJECTIVES

The locally advanced esophageal carcinoma can be complicated by fistulas. According to published data, the incidence rate of malignant esophageal fistulas is about 13%. The range of treatment modalities proposed by different authors varies from palliation to active and, if possible, radical surgical interventions. In the present study, we investigated combined esophagectomies as a radical treatment of the malignant esophageal fistulas.

METHODS

Thirty-five patients (aged 28--67) with malignant esophageal fistulas of different localizations were operated over a period from 1990 to 2000. The tumor was located in the upper, middle and lower thoracic esophagus in four, 20 and 11 cases, respectively. The malignant fistula with the mediastinum, pleural cavity, lungs, bronchi and trachea was observed in 21, two, five, four and three cases, respectively. Subtotal esophagectomy and esophagogastroplasty were performed in 18 patients; subtotal esophagectomy with intrapleural coloesophagoplasty was performed in one case; proximal gastric and lower thoracic esophageal resection from the left-side abdominothoracic approach was performed in three cases. Esophagogastric bypass anastomoses were formed in ten patients. Gastrostomy was performed in three patients.

RESULTS

The complication rate was 40% (14 out of 35); the postoperative mortality was 14.3% (five out of 35). In patients after esophageal resection, the mortality rate was 13.6% (three out of 22). With a median survival of 13 months (range, 3--31), the 2-year survival rate was 21% after combined esophagectomies.

CONCLUSIONS

The goal of surgery for esophageal cancer with various fistulas is to completely resect the primary tumor and involved adjacent structures with clear surgical margins and extended two-field lymphadenectomy. The importance of performing a complete resection is stressed by the absence of 1-year survivors among patients who underwent bypass surgery or gastrostomy. We consider that en-bloc combined resection of esophageal cancer complicated by fistula can be done with a low mortality.