BioXmark® liquid fiducials to enable radiotherapy tumor boosting in rectal cancer, a feasibility trial

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BioXmark® is a novel liquid fiducial marker for image-guided radiotherapy.

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The marker remained stable during chemoradiotherapy in 96% of rectal cancer cases.

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The fiducial allows for image tracking on CT-based imaging modalities.

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Marker visibility was good using CT-based imaging without any relevant artifacts.

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The marker is easy to inject without marker related adverse events.

Background and purpose

Dose-escalation in rectal cancer (RCa) may result in an increased complete response rate and thereby enable omission of surgery and organ preservation. In order to implement dose-escalation, it is crucial to develop a technique that allows for accurate image-guided radiotherapy. The aim of the current study was to determine the performance of a novel liquid fiducial marker (BioXmark®) in RCa patients during the radiotherapy course by assessing its positional stability on daily cone-beam CT (CBCT), technical feasibility, visibility on different imaging modalities and safety.

Materials and methods

Prospective, non-randomized, single-arm feasibility trial with inclusion of twenty patients referred for neoadjuvant chemoradiotherapy for locally advanced RCa. Primary study endpoint was positional stability on CBCT. Furthermore, technical aspects, safety and clinical performance of the marker, such as visibility on different imaging modalities, were evaluated.

Results

Seventy-four markers from twenty patients were available for analysis. The marker was stable in 96% of the cases. One marker showed clinically relevant migration, one marker was lost before start of treatment and one marker was lost during treatment. Marker visibility was good on computed tomography (CT) and CBCT, and moderate on electronic portal imaging (EPI). Marker visibility on magnetic resonance imaging (MRI) was poor during response evaluation.

Conclusion

The novel liquid fiducial marker demonstrated positional stability. We provide evidence of the feasibility of the novel fiducial marker for image-guided radiotherapy on daily cone beam CT for RCa patients.

The performance and safety of motorized spiral enteroscopy, including in patients with surgically altered gastrointestinal anatomy: a multicenter prospective study

BACKGROUND

Data are scarce on the efficacy and safety of motorized spiral enteroscopy (MSE). No data are available on the utility of this technique in patients with surgically altered gastrointestinal (GI) anatomy. We aimed to evaluate the safety and efficacy of MSE in patients with suspected small-bowel disease, including those with surgically altered GI anatomy.

METHODS

A multicenter prospective observational, uncontrolled study evaluated MSE in consecutive patients with suspected small-bowel pathology and an indication for diagnostic and/or therapeutic intervention.

RESULTS

A total of 170 patients (102 men; median age 64 years, range 18-89) were included. The overall diagnostic yield was 64.1 %. Endotherapy was performed in 53.5 % of procedures. The median total procedure times for the antegrade and retrograde approaches were 45 minutes (interquartile range [IQR] 30-80) and 40 minutes (IQR 30-70), respectively. When total (pan)enteroscopy was intended, this was achieved at rate of 70.3 % (28.1 % by antegrade approach and 42.2 % by a bidirectional approach). Surgically altered GI anatomy was present in 34 /170 of all procedures (20.0 %) and in 11 /45 of the successful total enteroscopy procedures (24.4 %). Propofol sedation or general anesthesia were used in 92.9 % and 7.1 % of the procedures, respectively. Minor adverse events were observed in 15.9 % of patients, but there were no major adverse events.

CONCLUSION

MSE seems to be an effective and safe endoscopic procedure. Total (pan)enteroscopy can be achieved, in one or two sessions, even in the presence of surgically altered GI anatomy. The total procedure time is relatively short. For both antegrade and retrograde MSE procedures, propofol sedation seems sufficient and safe.

Epidemiological, clinical and endoscopic characteristics of colorectal neuroendocrine neoplasms: a population-based study in the Netherlands

Background and study aims  Neuroendocrine neoplasms (NEN) account for a small number of colorectal neoplasms. Endoscopic detection is essential for diagnosis, treatment and follow-up. Little is known about incidence of NENs in colonoscopy populations or the relationship between clinical, endoscopic and histopathologic features. We evaluated epidemiology, endoscopic and clinical characteristics of colorectal NENs in a population-based cohort. Patients and methods  Medical records of NEN cases were cross-linked with the national pathology database from January 2001 to December 2015, in South Limburg County, the Netherlands, covering four endoscopy units. Senior pathologists reviewed and classified NENs using World Health Organization 5th edition (2019) guidelines. Results  The number of colorectal NEN diagnoses was stable over time with 0.6 NEN per 1,000 patients. A total of NENs were detected in 85 patients: 65 neuroendocrine tumors (NETs) and 20 poorly differentiated neuroendocrine carcinomas (NECs). Rectal NETs were usually small sessile/submucosal lesions with yellowish (lipoma-like) color. Colonic NETs were larger sessile/submucosal lesions with darker color compared to background. Colorectal NECs presented as large, dark-colored lesions with ulcerated/necrotizing areas. Conclusions  Our population-based data point to a stable and low incidence of 0.6 NEN per 1,000 patients in the Netherlands. Rectal NETs mainly present as small sessile yellowish lesions. Colonic NETs present as larger and darker lesions than background mucosa and NECs as darker lesions than background with ulceration/necrosis. Standardized endoscopic characterization of colorectal NENs is necessary to improve recognition of these lesions and provide a basis for evidence-based treatment and surveillance recommendations.

Endoscopic full-thickness resection of T1 colorectal cancers: a retrospective analysis from a multicenter Dutch eFTR registry

BACKGROUND

Complete endoscopic resection and accurate histological evaluation for T1 colorectal cancer (CRC) are critical in determining subsequent treatment. Endoscopic full-thickness resection (eFTR) is a new treatment option for T1 CRC < 2 cm. We aimed to report clinical outcomes and short-term results.

METHODS

Consecutive eFTR procedures for T1 CRC, prospectively recorded in our national registry between November 2015 and April 2020, were retrospectively analyzed. Primary outcomes were technical success and R0 resection. Secondary outcomes were histological risk assessment, curative resection, adverse events, and short-term outcomes.

RESULTS

We included 330 procedures: 132 primary resections and 198 secondary scar resections after incomplete T1 CRC resection. Overall technical success, R0 resection, and curative resection rates were 87.0 % (95 % confidence interval [CI] 82.7 %-90.3 %), 85.6 % (95 %CI 81.2 %-89.2 %), and 60.3 % (95 %CI 54.7 %-65.7 %). Curative resection rate was 23.7 % (95 %CI 15.9 %-33.6 %) for primary resection of T1 CRC and 60.8 % (95 %CI 50.4 %-70.4 %) after excluding deep submucosal invasion as a risk factor. Risk stratification was possible in 99.3 %. The severe adverse event rate was 2.2 %. Additional oncological surgery was performed in 49/320 (15.3 %), with residual cancer in 11/49 (22.4 %). Endoscopic follow-up was available in 200/242 (82.6 %), with a median of 4 months and residual cancer in 1 (0.5 %) following an incomplete resection.

CONCLUSIONS

eFTR is relatively safe and effective for resection of small T1 CRC, both as primary and secondary treatment. eFTR can expand endoscopic treatment options for T1 CRC and could help to reduce surgical overtreatment. Future studies should focus on long-term outcomes.

Evaluation of polypectomy quality indicators of large nonpedunculated colorectal polyps in a nonexpert, bowel cancer screening cohort

BACKGROUND AND AIMS

With the introduction of the national bowel cancer screening program, the detection of sessile and flat colonic lesions ≥20 mm in size, defined as large nonpedunculated colorectal polyps (LNPCPs), has increased. The aim of this study was to examine the quality of endoscopic treatment of LNPCPs in the Dutch screening program.

METHODS

This investigation comprised 2 related, but separate, substudies (1 with a cross-sectional design and 1 with a longitudinal design). The first examined prevalence and characteristics of LNPCPs in data from the national Dutch screening cohort from February 2014 until January 2017. The second, with screening data from 5 endoscopy units in the Southern part of the Netherlands from February 2014 until August 2015, examined performance on important quality indicators (technical and clinical successes, recurrence rate, adverse event rate, and surgery referral rate). All patients were part of the national Dutch screening cohort.

RESULTS

In the national cohort, an LNPCP was detected in 8% of participants. Technical and clinical success decreased with increasing LNPCP size, from 93% and 96% in 20- to 29-mm lesions to 85% and 86% in 30- to 39-mm lesions and to 74% and 81% in ≥40-mm lesions (P < .001; P = .034). The cumulative recurrence rate at 12 months increased with LNPCP size, from 9% to 22% and 26% in the respective size groups (P = .095). The adverse event rate was 5%. The overall surgical referral rate for noninvasive LNPCPs was 7%.

CONCLUSIONS

In this performance of 2 substudies, it was shown that quality parameters for endoscopic resection of large polyps in the Dutch screening cohort are not reached, especially in ≥30-mm polyps. Endoscopic resection of large polyps could benefit from additional training, quality monitoring, and centralization either within or between centers.

Metachronous neoplasms in patients with laterally spreading tumours during surveillance

Background

Laterally spreading tumours represent a major challenge for endoscopic detection and resection.

Objective

To examine synchronous and metachronous neoplasms in patients with laterally spreading tumours.

Methods

We prospectively collected colonoscopy and histopathology data from patients who underwent colonoscopy in our centre at up to 6 years' follow‐up. Post‐resection surveillance outcomes between laterally spreading tumours, flat colorectal neoplasms 10 mm or greater, and large polypoid colorectal neoplasms, polypoid colorectal neoplasms 10 mm or greater, were compared.

Results

Between 2008 and 2012, 8120 patients underwent colonoscopy for symptoms (84.6%), screening (6.7%) or surveillance (8.7%). At baseline, 151 patients had adenomatous laterally spreading tumours and 566 patients had adenomatous large polypoid colorectal neoplasms. Laterally spreading tumour patients had more synchronous colorectal neoplasms than large polypoid colorectal neoplasm patients (mean 3.34 vs. 2.34, p < 0.001). Laterally spreading tumour patients significantly more often developed metachronous colorectal neoplasms (71.6% vs. 54.2%, p = 0.0498) and colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients (36.4% vs. 15.8%, p < 0.001). After correction for age and gender, laterally spreading tumour patients were more likely than large polypoid colorectal neoplasm patients to develop a colorectal neoplasm with high grade dysplasia or submucosal invasion (hazard ratio 2.9, 95% confidence interval 1.8–4.6). The risk of metachronous colorectal cancer was not significantly different in laterally spreading tumours compared to large polypoid colorectal neoplasm patients.

Conclusion

Patients with laterally spreading tumours developed more metachronous colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients. Based on these findings endoscopic treatment and surveillance recommendations for patients with laterally spreading tumours should be optimised.

Summarize the established knowledge on this subject

Laterally spreading tumours (LSTs) are a heterogeneous group of large, predominantly benign flat neoplasms that can be endoscopically treated, requiring additional time and expertise

LSTs consist of different endoscopic subtypes which are predictive of the risk of submucosal invasion (SMI)

Patients with LSTs harbour more synchronous neoplasms than patients with large polypoid colorectal neoplasms (LP‐CRNs)

What are the significant and/or new findings of this study?

Patients with LSTs more frequently have metachronous neoplasms than patients with LP‐CRNs, justifying strict surveillance

LSTs can be effectively managed by conventional endoscopic resections in most cases

Endoscopic full-thickness resection (eFTR) of colorectal lesions: results from the Dutch colorectal eFTR registry

BACKGROUND

Endoscopic full-thickness resection (eFTR) is a minimally invasive resection technique that allows definite diagnosis and treatment for complex colorectal lesions ≤ 30 mm unsuitable for conventional endoscopic resection. This study reports clinical outcomes from the Dutch colorectal eFTR registry.

METHODS

Consecutive patients undergoing eFTR in 20 hospitals were prospectively included. The primary outcome was technical success, defined as macroscopic complete en bloc resection. Secondary outcomes were: clinical success, defined as tumor-free resection margins (R0 resection); full-thickness resection rate; and adverse events. RESULTS : Between July 2015 and October 2018, 367 procedures were included. Indications were difficult polyps (non-lifting sign and/or difficult location; n = 133), primary resection of suspected T1 colorectal cancer (CRC; n = 71), re-resection after incomplete resection of T1 CRC (n = 150), and subepithelial tumors (n = 13). Technical success was achieved in 308 procedures (83.9 %). In 21 procedures (5.7 %), eFTR was not performed because the lesion could not be reached or retracted into the cap. In the remaining 346 procedures, R0 resection was achieved in 285 (82.4 %) and full-thickness resection in 288 (83.2 %). The median diameter of resected specimens was 23 mm. Overall adverse event rate was 9.3 % (n = 34/367): 10 patients (2.7 %) required emergency surgery for five delayed and two immediate perforations and three cases of appendicitis. CONCLUSION : eFTR is an effective and relatively safe en bloc resection technique for complex colorectal lesions with the potential to avoid surgery. Further studies assessing the role of eFTR in early CRC treatment with long-term outcomes are needed.

Colonoscopy is safe and not associated with higher pain scores in patients with hypermobility spectrum disorder: results from an exploratory prospective study

BACKGROUND

Patient perception of colonoscopy varies greatly. Young slender women and patients with irritable bowel syndrome (IBS) appear to be at risk for periprocedural pain. Recent evidence suggests a high prevalence of joint hypermobility related connective tissue disorders in this population. Therefore, we aimed to investigate whether hypermobility spectrum disorder (HSD) is associated with increased pain during colonoscopy.

METHODS

We prospectively included patients undergoing routine colonoscopy. Subjects were assessed for HSD using the 2017 criteria, and IBS and functional dyspepsia using the Rome III criteria. After colonoscopy and recovery from sedation, patients were asked to report pain scores on a 100-mm visual analogue scale (VAS). In addition, caecal intubation time was measured, endoscopists scored the difficulty of the procedure (100-mm VAS) and procedure-related adverse events were registered.

RESULTS

Of 200 included patients, 22 (11%) met criteria for HSD. A female predominance was observed in patients with HSD (86.4% versus 49.4%, p < 0.001). A crude linear regression model demonstrated that pain scores were 13.30 mm higher in patients with HSD versus non-HSD patients (95% CI 0.07 - 26.53, p = 0.049). When subsequently correcting for possible confounding factors, however, this difference in pain scores could be explained by a confounding effect of female gender. Caecal intubation time, perceived procedural difficulty and complication rate did not differ significantly between groups.

CONCLUSION

HSD does not seem to be a predictor of painful colonoscopy, probably due to female gender as a confounding factor. In addition, performing colonoscopy is not more complicated in patients with HSD versus non-HSD patients, nor is it associated with more adverse events.

Optical diagnosis of diminutive polyps in the Dutch Bowel Cancer Screening Program: Are we ready to start?

Background and study aims  Implementation of optical diagnosis of diminutive polyps may potentially increase the efficacy and cost-effectiveness of colonoscopies. To adopt such strategy in clinical practice, the Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) thresholds provide the basis to be met: ≥ 90 % negative predictive value (NPV) for diagnosis of adenomatous histology and ≥ 90 % agreement on surveillance intervals. We evaluated this within the Dutch Bowel Cancer Screening Program (BCSP). Patients and methods  Endoscopic and histological data were collected from participants of the national bowel cancer screening program with an unfavorable fecal immunochemical test referred for colonoscopy between February 2014 and August 2015 at four endoscopy centers. The "resect and discard" scenario was studied, resecting diminutive polyps without histological evaluation. Agreement between optical diagnosis and histological diagnosis was measured for surveillance intervals according to Dutch, European and American post-polypectomy surveillance guideline. Results  Fifteen certified endoscopists participated in this study and included 3028 diminutive polyps. In 2,330 patients both optical and histological diagnosis were available. Optical diagnosis of diminutive polyps showed NPV of 84 % (95 % CI 80-87) for adenomatous histology in the rectosigmoid. Applying the 'resect and discard' strategy resulted in 90.6 %, 91.2 %, 90.9 % agreement on surveillance intervals for the Dutch, European and American guideline respectively. Conclusion  Our data representing current clinical practice in the Dutch BCSP practice on optical diagnosis of diminutive polyps showed that accuracy of predicting histology remains challenging, and risk of incorrect optical diagnosis is still significant. Therefore, it is too early to safely implement these strategies.

Therapeutic strategies in gastroparesis: Results of stepwise approach with diet and prokinetics, Gastric Rest, and PEG-J: A retrospective analysis

BACKGROUND

Gastroparesis is characterized by abnormal gastric motor function with delayed gastric emptying in the absence of mechanical obstruction. In our tertiary referral center, patients are treated with a stepwise approach, starting with dietary advice and prokinetics, followed by three months of nasoduodenal tube feeding with "gastric rest." When not successful, a percutaneous endoscopic gastrostomy with jejunal extension (PEG-J) for long-term enteral feeding is placed.

AIM

To evaluate the effect of this stepwise approach on weight and symptoms.

METHODS

Analyses of data of all referred gastroparesis patients between 2008 and 2016.

KEY RESULTS

A total of 86 patients (71% female, 20-87 years [mean 55.8 years]) were analyzed of whom 50 (58%) had adequate symptom responses to diet and prokinetics. The remaining 36 (decompensated gastroparesis) were treated with three months gastric rest. Symptom response rate was 47% (17/36). Significant weight gain was seen in all patients, independent of symptom response. In the remaining 19 symptom non-responders, the enteral feeding was continued through PEG-J. Treatment was effective (symptoms) in 37%, with significant weight gain in all. In 84% of patients, the PEG-J is still in use (mean duration 962 days).

CONCLUSIONS AND INFERENCES

Following a stepwise treatment approach in gastroparesis, adequate symptom response was reached in 86% of all patients. Weight gain was achieved in all patients, independent of symptom response. Diet and prokinetics were effective with regard to symptoms in 58%, temporary gastric rest in 47%, and PEG-J as third step in 37% of patients.

Stent-induced compression necrosis for the endoscopic removal of a partially eroded Lap-Band

Endoscopic removal of eroded Lap-Bands is a minimally invasive alternative to surgical removal that prerequires sufficient erosion through the gastric wall, that is, ≥180° of the gastro-oesophageal wall circumference. A 69-year-old woman presented with dysphagia due to a long-standing Lap-Band erosion, currently of a 60° circumference. Adhesions due to her extensive surgical history rendered surgical treatment undesirable, so a self-expanding stent was placed endoscopically to induce sufficient erosion for subsequent endoscopic removal. During therapy, the patient complained of ructus and dysphagia, probably related to an overly proximally (oesophageal) positioned stent. After a total of 12 weeks, far longer than the described stenting duration in the literature, the Lap-Band was found free in the gastric lumen and was successfully removed using an endoscopic loop. Stent-induced compression necrosis should be considered as a minimally invasive treatment option for Lap-Bands eroded for <180°, with caution in the context of extensive fibrosis.

Endoscopic characterization of sessile serrated adenomas/polyps with and without dysplasia

BACKGROUND AND STUDY AIMS

Sessile serrated adenomas/polyps (SSA/Ps) are precursors of colorectal cancer (CRC), but their endoscopic detection can be difficult. We therefore examined the endoscopic characteristics of SSA/Ps with and without dysplasia in a cross-sectional study.

PATIENTS AND METHODS

We reviewed clinical, endoscopic, and histopathologic data from patients undergoing colonoscopy between February 2008 and February 2012. We categorized colorectal polyps according to anatomic site, size, and shape, and classified serrated polyps using the World Health Organization (WHO) classification. Multiple logistic regression analyses examined potential differences regarding site, size, and shape between SSA/Ps and colorectal adenomas (overall and advanced only).

RESULTS

We examined 7433 patients (mean age 59 years, 45.9 % men) with 5968 colorectal polyps. In total, we found 170 SSA/Ps (170/5968, 2.9 %), including 63 SSA/Ps with dysplasia (1.1 %) and 107 SSA/Ps without dysplasia (1.8 %). Compared with SSA/Ps with dysplasia, SSA/Ps without dysplasia were more often proximally located (odds ratio [OR] 3.3, 95 % confidence interval [95 %CI] 1.7 - 6.4), but less often < 6 mm in size (OR 0.6, 95 %CI 0.3 - 1.1). No significant differences were found regarding location between SSA/Ps with dysplasia and advanced adenomas (proximal colon, 47.6 % vs. 40.1 %). However, SSA/Ps with dysplasia were more often < 6 mm in size than advanced adenomas (OR 0.3, 95 %CI 0.2 - 0.5). Of the 63 dysplastic SSA/Ps, 6 (9.5 %) contained high grade dysplasia, but none invasive carcinoma.

CONCLUSIONS

SSA/Ps with dysplasia are frequently < 6 mm in size, located throughout the colon and 9.5 % of them contain high grade dysplasia. These findings underscore the importance of high quality colonoscopic examination to maximize protection against CRC.

Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience

AIM: To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience.

METHODS: We used a digital library of HD i-scan still images, comprising twin pictures (surface enhancement and tone enhancement), collected at our university hospital. We defined endoscopic features of adenomatous and non-adenomatous polyps, according to the following parameters: color, surface pattern and vascular pattern. We familiarized the participating endoscopists on optical diagnosis of colorectal polyps using a 20-min didactic training session. All endoscopists were asked to evaluate an image set of 50 colorectal polyps with regard to polyp histology. We classified the diagnoses into high confidence (i.e., cases in which the endoscopist could assign a diagnosis with certainty) and low confidence diagnoses (i.e., cases in which the endoscopist preferred to send the polyp for formal histology). Mean sensitivity, specificity and accuracy per endoscopist/image were computed and differences between groups tested using independent-samples t tests. High vs low confidence diagnoses were compared using the paired-samples t test.

RESULTS: Eleven endoscopists without previous experience on optical diagnosis evaluated a total of 550 images (396 adenomatous, 154 non-adenomatous). Mean sensitivity, specificity and accuracy for diagnosing adenomas were 79.3%, 85.7% and 81.1%, respectively. No significant differences were found between gastroenterologists and trainees regarding performances of optical diagnosis (mean accuracy 78.0% vs 82.9%, P = 0.098). Diminutive lesions were predicted with a lower mean accuracy as compared to non-diminutive lesions (74.2% vs 93.1%, P = 0.008). A total of 446 (81.1%) diagnoses were made with high confidence. High confidence diagnoses corresponded to a significantly higher mean accuracy than low confidence diagnoses (84.0% vs 64.3%, P = 0.008). A total of 319 (58.0%) images were evaluated as having excellent quality. Considering excellent quality images in conjunction with high confidence diagnosis, overall accuracy increased to 92.8%.

CONCLUSION: After a single training session, endoscopists with varying levels of experience can already provide optical diagnosis with an accuracy of 84.0%.