Targeted transcriptomic analysis of pancreatic adenocarcinoma in EUS-FNA samples by NanoString technology

Background: Integration of transcriptomic testing into EUS-FNA samples is a growing need for precision oncology in pancreatic ductal adenocarcinoma (PDAC). The NanoString platform is suitable for transcriptome profiling in low yield RNA samples. Methods: Inclusion of patients that underwent EUS-FNA cytological diagnosis of pancreatic ductal adenocarcinoma using 19G and/or 22G needles and subsequent surgical resection. Formalin-fixed, paraffin-embedded (FFPE) cytological and surgical samples underwent RNA extraction and transcriptomic analysis using a custom 52-gene NanoString panel of stromal PDAC features. Cell type abundance was quantified in FFPE specimens and correlated. Results: 18 PDAC patients were included. Mean EUS-FNA passes was 2 + 0.7. All FFPE passed the RNA quality control for genomic analysis. Hierarchical clustering on the global gene expression data showed that genes were differentially expressed between EUS and surgical samples. A more enriched cancer-associated fibroblasts and epithelial-mesenchymal transition transcriptomic profile was observed across surgical specimens whereas immunological biomarkers were more represented in EUS-FNA samples. Cytological examination confirmed a scanty representation of CAF and more immunological cell abundance in cytological samples in comparison to surgical specimens. Conclusion: Targeted transcriptomic NanoString profiling of PDAC samples obtained by EUS-FNA is a feasible approach for pre-surgical molecular analysis although stromal CAF/EMT mRNA biomarkers are underrepresented.

Safety and efficacy of endoscopic vacuum therapy for the treatment of perforations and anastomotic leaks of the upper gastrointestinal tract

AIM

To evaluate the efficacy and safety of endoscopic vacuum therapy (EVT) in the management of perforations and anastomotic leaks of the upper gastrointestinal tract.

PATIENTS AND METHODS

This is a retrospective observational study which included patients who underwent EVT due to any upper gastrointestinal defect between April 2017 and February 2019 in three Spanish Hospitals. To this end, we used the only medical device approved to date for endoscopic use (Eso-SPONGEr; B. Braun Melsungen AG, Melsungen, Germany).

RESULTS

11 patients were referred for EVT of an anastomotic leak after esophagectomy (n=7), gastrectomy (n=2), esophageal perforation secondary to endoscopic Zenker's septomiotomy (n=1) and Boerhaave syndrome (n=1). The median size of the cavity was 8×3cm. The median delay between surgery and EVT was 7 days. The median of EVT duration was 28 days. The median number of sponges used was 7 and the mean period replacement was 3.7 days. In 10 cases (91%), the defect was successfully closed. In 9 cases (82%) clinical resolution of the septic condition was achieved. 5 patients presented some adverse event: 3 anastomotic strictures, 1 retropharyngeal pain and 1 case of new-onset pneumonia. The median hospital stay from the start of EVT was 45 days. 1 patient died owing to septic complications secondary to the anastomotic leak.

CONCLUSION

EVT was successful in over 90% of perforations and anastomotic leaks of the upper gastrointestinal tract. Moreover, this is a safe therapy with only mild adverse events associated.

Endoscopic ultrasound-guided fine-needle aspiration and trucut biopsy in the diagnosis of gastric stromal tumors: a randomized crossover study

BACKGROUND AND AIM

The diagnosis of gastrointestinal stromal tumors (GISTs) has important prognostic and therapeutic implications. The specific diagnosis of GIST has to be based on immunocytochemistry. This study aimed to prospectively compare in a crossover manner the accuracy of endoscopic ultrasound (EUS)-guided fine-needle aspiration (EUS-FNA) and EUS-guided trucut biopsy (EUS-TCB) in the specific diagnosis of gastric GISTs. We hypothesized that EUS-TCB is superior to EUS-FNA in this respect.

PATIENTS AND METHODS

Forty patients with gastric subepithelial tumors suspected on the basis of EUS of being a GIST underwent both EUS-FNA and EUS-TCB. The sequence in which the techniques were employed was randomly assigned to avoid bias.

RESULTS

Forty tumors were sampled (mean number of passes: 2.1 +/- 0.9 with EUS-TNB and 1.9 +/- 0.8 with EUS-FNA; P = not significant, NS). Final diagnoses were: GIST (n = 27), carcinoma (n = 2), leiomyoma (n = 1), schwannoma (n = 1), and no diagnosis possible (n = 9). Device failure occurred in 6 patients with EUS-TCB. A cytohistological diagnosis of mesenchymal tumor (n = 29) and carcinoma (n = 2) was made in 70 % of cases by EUS-FNA and in 60 % of cases by EUS-TCB ( P = NS). Among the samples that were adequate, immunohistochemistry could be performed in 74 % of EUS-FNA samples and in 91 % of EUS-TCB samples ( P = 0.025). When inadequate samples were included, the overall diagnostic accuracy of EUS-FNA was 52 % and that of EUS-TCB was 55 % ( P = NS). There were no complications.

CONCLUSIONS

EUS-TCB is not superior to EUS-FNA in GISTs because of the high rate of technical failure of trucut. However, when an adequate sample is obtained with EUS-TCB, immunohistochemical phenotyping is almost always possible. EUS-TCB can be safely performed in this set of patients.

Incidence and clinical significance of hyperamylasemia after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic lesions: a prospective and controlled study

BACKGROUND AND STUDY AIM

Acute pancreatitis as a complication of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic lesions is rarely observed. However, there is little information on the incidence of hyperamylasemia after EUS-FNA of the pancreas and its clinical significance. This study aimed to supply this lack of information.

PATIENTS AND METHODS

Patients who underwent EUS-FNA of a pancreatic lesion between October 2004 and October 2005 were studied prospectively. Exclusion criteria were: (i) platelet count under 50,000/mm (3) and/or prothrombin time < 50 %; (ii) performance of surgery, endoscopic retrograde cholangiopancreatography (ERCP), a percutaneous biopsy attempt, or another invasive procedure within 7 days before EUS-FNA; (iii) lack of informed consent. Serum amylase levels were determined before and 8 and 24 h after the procedure. Hyperamylasemia was defined by amylase levels above 104 UI/L (and higher than baseline levels) 8 h after the procedure. Acute pancreatitis was defined by upper abdominal pain (with or without nausea and/or vomiting) accompanied by elevation of serum amylase or lipase to at least twice baseline levels.

RESULTS

A total of 100 patients underwent EUS-FNA of a pancreatic lesion (58 men, 42 women; mean age 60 +/- 13 years). Eleven patients (11 %) showed hyperamylasemia 8 h after the puncture (298 +/- 293 UI/L, range 105 - 1044 UI/L), but only two of them developed acute mild pancreatitis after EUS-FNA. Hyperamylasemia was not related either to the type of lesion (cystic or solid) or to its location, the duration of the procedure, or the number of passes performed.

CONCLUSIONS

Pancreatitis after pancreatic EUS-FNA occurs in 2 % of patients, with some more cases of silent hyperamylasemia. This complication may have to be included in the information given to patients for their informed consent.