The Role of Probe-Based Confocal Laser Endomicroscopy (pCLE) in the Diagnosis of Sustained Clinical Complete Response Under Watch-and-Wait Strategy After Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Adenocarcinoma: a Score Validation

BACKGROUND

Watch-and-wait strategy has been increasingly accepted for patients with clinical complete response (cCR) after multimodal treatment for locally advanced rectal adenocarcinoma. Close follow-up is essential to the early detection of local regrowth. It was previously demonstrated that probe-based confocal laser endomicroscopy (pCLE) scoring using the combination of epithelial and vascular features might improve the diagnostic accuracy of cCR.

AIM

To validate the pCLE scoring system in the assessment of patients with cCR after neoadjuvant chemoradiotherapy (nCRxt) for advanced rectal adenocarcinoma.

METHODS

Digital rectal examination, pelvic magnetic resonance imaging (MRI), and pCLE were performed in 43 patients with cCR, who presented either a scar (N = 33; 76.7%) or a small ulcer with no signs of tumor, and/or biopsy negative for malignancy (N = 10; 23.3%).

RESULTS

Twenty-five (58.1%) patients were men, and the mean age was 58.4 years. During the follow-up, 12/43 (27.9%) patients presented local regrowth and underwent salvage surgery. There was an association between pCLE diagnostic scoring and final histological report (for patients who underwent surgical resection) or final diagnosis at the latest follow-up (p = 0.0001), while this association was not observed with MRI (p = 0.49). pCLE sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66.7%, 93.5%, 80%, 88.9%, and 86%, respectively. MRI sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66.7%, 48.4%, 66.7%, 78.9%, and 53.5%, respectively.

CONCLUSIONS

pCLE scoring system based on epithelial and vascular features improved the diagnosis of sustained cCR and might be recommended during follow-up. pCLE might add some valuable contribution for identifying local regrowth. Trial Registration This protocol was registered at the Clinical Trials (ClinicalTrials.gov identifier NCT02284802).

UNDERWATER ENDOSCOPIC MUCOSAL RESECTION FOR SMALL RECTAL NEUROENDOCRINE TUMORS

BACKGROUND

A common site of neuroendocrine tumors (NETs) is the rectum. The technique most often used is endoscopic mucosal resection with saline injection. However, deep margins are often difficult to obtain because submucosal invasion is common. Underwater endoscopic mucosal resection (UEMR) is a technique in which the bowel lumen is filled with water rather than air, precluding the need for submucosal lifting.

OBJECTIVE

This study aimed to evaluate the efficacy and safety of UEMR for removing small rectal neuroendocrine tumors (rNETs).

METHODS

Retrospective study with patients who underwent UEMR in two centers. UEMR was performed using a standard colonoscope. No submucosal injection was performed. Board-certified pathologists conducted histopathologic assessment.

RESULTS

UEMR for small rNET was performed on 11 patients (nine female) with a mean age of 55.8 years and 11 lesions (mean size 7 mm, range 3-12 mm). There were 9 (81%) patients with G1 rNET and two patients with G2, and all tumors invaded the submucosa with only one restricted to the mucosa. None case showed vascular or perineural invasion. All lesions were removed en bloc. Nine (81%) resections had free margins. Two patients had deep margin involvement; one had negative biopsies via endoscopic surveillance, and the other was lost to follow-up. No perforations or delayed bleeding occurred.

CONCLUSION

UEMR appeared to be an effective and safe alternative for treatment of small rNETs without adverse events and with high en bloc and R0 resection rates. Further prospective studies are needed to compare available endoscopic interventions and to elucidate the most appropriate endoscopic technique for resection of rNETs.

UNDERWATER ENDOSCOPIC MUCOSAL RESECTION FOR NON-PEDUNCULATED COLORECTAL LESIONS. A PROSPECTIVE SINGLE-ARM STUDY

BACKGROUND

Underwater endoscopic mucosal resection (UEMR) has emerged as a revolutionary method allowing resection of colorectal lesions without submucosal injection. Brazilian literature about this technique is sparse.

OBJECTIVE

The aim of this study was evaluate the efficacy and safety of UEMR technique for removing non-pedunculated colorectal lesions in two Brazilian tertiary centers.

METHODS

This prospective study was conducted between June 2016 and May 2017. Naïve and non-pedunculated lesions without signs of submucosal invasion were resected using UEMR technique.

RESULTS

A total of 55 patients with 65 lesions were included. All lesions, except one, were successfully and completely removed by UEMR (success rate 98.5%). During UEMR, two cases of bleeding were observed (3.0%). One patient had abdominal pain on the day after resection without pneumoperitoneum. There was no perforation or delayed bleeding.

CONCLUSION

This study supports the existing data indicating acceptable rates of technical success, and low incidence of adverse events with UEMR. The results of this Brazilian study were consistent with previous abroad studies.

Probe-based confocal endomicroscopy is accurate for differentiating gastric lesions in patients in a Western center

Objective

Probe-based confocal laser endomicroscopy (pCLE) technique may improve the diagnosis of gastric mucosal lesions allowing acquisition of high-resolution in vivo images at the cellular and microvascular levels. This study aims to evaluate the accuracy of pCLE for the differential diagnosis of non-neoplastic and neoplastic gastric lesions.

Methods

Twenty gastric mucosal lesions from 10 patients were evaluated during endoscopic procedure and were examined by pCLE. Diagnostic pCLE was followed by biopsies or endoscopic resection of suspected lesions. A senior pathologist evaluated the specimens and was blinded to the pCLE results.

Results

Patients' mean age was 68.3 (range, 42-83) years and six were men. Thirteen suspicious flat or elevated lesions (classified as 0-Is, 0-IIa or 0-IIa + IIc) and seven pre-malignant lesions (atrophy and intestinal metaplasia) were evaluated. One patient was studied during his long-term follow-up after partial gastrectomy and presented severe atrophy, intestinal metaplasia, and xanthomas at the stump mucosa. The location of gastric lesions was in the body (n=10 lesions), the antrum (n=9) and the incisura angularis (n=1). All neoplastic lesions and all but one benign lesion were properly diagnosed by pCLE. pCLE incorrectly diagnosed one small antrum lesion as adenoma, however the final diagnosis was intestinal metaplasia. The final histological diagnosis was neoplastic in 9 and benign lesions in 11. In this small case series, pCLE accuracy was 95% (19/20 lesions).

Conclusions

pCLE is accurate for real time histology of gastric lesions. pCLE may change the management of patients with gastric mucosal lesions, guiding biopsies and endoscopic resection, and avoiding further diagnostic workup or unnecessary therapy.

Comparison of the pull and introducer percutaneous endoscopic gastrostomy techniques in patients with head and neck cancer

BACKGROUND AND STUDY AIMS

Percutaneous endoscopic gastrostomy (PEG) in head and neck cancer (HNC) patients is associated with higher complication and mortality rates when compared to a general patient population. The pull technique is still the preferred technique worldwide but it has some limitations. The aim of this study is to compare the pull and introducer PEG techniques in patients with HNC.

PATIENTS AND METHODS

This study is based on a retrospective analysis of a prospectively collected database of 309 patients with HNC who underwent PEG in the Cancer Institute of São Paulo.

RESULTS

The procedure was performed with the standard endoscope in 205 patients and the introducer technique was used in 137 patients. There was one procedure-related mortality. Age, sex and albumin level were similar in both groups. However in the introducer technique group, patients had a higher tumor stage, a lower Karnofsky status, and presented more frequently with tracheostomy and trismus. Overall, major, minor, immediate and late complications and 30-day mortality rates were similar but the introducer technique group presented more minor bleeding and tube dysfunctions.

CONCLUSION

The push and introducer PEG techniques seem to be both safe and effective but present different complication profiles. The choice of PEG technique in patients with HNC should be made individually.