External validation of ¹⁸F-FDG PET-based radiomic models on identification of residual oesophageal cancer after neoadjuvant chemoradiotherapy

Objectives Detection of residual oesophageal cancer after neoadjuvant chemoradiotherapy (nCRT) is important to guide treatment decisions regarding standard oesophagectomy or active surveillance. The aim was to validate previously developed 18F-FDG PET-based radiomic models to detect residual local tumour and to repeat model development (i.e. 'model extension') in case of poor generalisability. Methods This was a retrospective cohort study in patients collected from a prospective multicentre study in four Dutch institutes. Patients underwent nCRT followed by oesophagectomy between 2013 and 2019. Outcome was tumour regression grade (TRG) 1 (0% tumour) versus TRG 2-3-4 (≥1% tumour). Scans were acquired according to standardised protocols. Discrimination and calibration were assessed for the published models with optimism-corrected AUCs &gt;0.77. For model extension, the development and external validation cohorts were combined. Results Baseline characteristics of the 189 patients included [median age 66 years (interquartile range 60-71), 158/189 male (84%), 40/189 TRG 1 (21%) and 149/189 (79%) TRG 2-3-4] were comparable to the development cohort. The model including cT stage plus the feature 'sum entropy' had best discriminative performance in external validation (AUC 0.64, 95% confidence interval 0.55-0.73), with a calibration slope and intercept of 0.16 and 0.48 respectively. An extended bootstrapped LASSO model yielded an AUC of 0.65 for TRG 2-3-4 detection. Conclusion The high predictive performance of the published radiomic models could not be replicated. The extended model had moderate discriminative ability. The investigated radiomic models appeared inaccurate to detect local residual oesophageal tumour and cannot be used as an adjunct tool for clinical decision-making in patients.</p

Detection and localization of early- and late-stage cancers using platelet RNA

Cancer patients benefit from early tumor detection since treatment outcomes are more favorable for less advanced cancers. Platelets are involved in cancer progression and are considered a promising biosource for cancer detection, as they alter their RNA content upon local and systemic cues. We show that tumor-educated platelet (TEP) RNA-based blood tests enable the detection of 18 cancer types. With 99% specificity in asymptomatic controls, thromboSeq correctly detected the presence of cancer in two-thirds of 1,096 blood samples from stage I–IV cancer patients and in half of 352 stage I–III tumors. Symptomatic controls, including inflammatory and cardiovascular diseases, and benign tumors had increased false-positive test results with an average specificity of 78%. Moreover, thromboSeq determined the tumor site of origin in five different tumor types correctly in over 80% of the cancer patients. These results highlight the potential properties of TEP-derived RNA panels to supplement current approaches for blood-based cancer screening

GATA6 expression in Barrett's oesophagus and oesophageal adenocarcinoma

BACKGROUND: Barrett's oesophagus can progress towards oesophageal adenocarcinoma through a metaplasia-dysplasia-carcinoma sequence, but the underlying mechanisms are poorly understood. The transcription factor GATA6 is known to be involved in columnar differentiation and proliferation, and GATA6 gene amplification was recently linked with poor survival in oesophageal adenocarcinoma. AIM: To study the expression of GATA6 during Barrett's oesophagus development and malignant transformation. To determine the prognostic value of GATA6 in oesophageal adenocarcinoma. METHODS: Two retrospective cohorts were derived from the pathological archive of the University Medical Center Groningen. The first cohort contained 130 tissue samples of normal squamous epithelium, metaplasia, dysplasia and oesophageal adenocarcinoma. The second cohort consisted of a tissue microarray containing tissue from 92 oesophageal adenocarcinoma patients. Immunohistochemistry was used to examine GATA6 protein expression and to correlate GATA6 expression in oesophageal adenocarcinoma with overall and disease-free survival. RESULTS: The percentage of GATA6-positive cells was low in squamous epithelium (10%) but increased progressively in Barrett's oesophagus (30%, P<0.001) and high-grade dysplasia (82%, P=0.005). GATA6 expression was not associated with overall or disease-free survival in oesophageal adenocarcinoma patients (P=0.599 and P=0.700 respectively). CONCLUSION: GATA6 expression is progressively increased during Barrett's oesophagus development and its malignant transformation. However, no prognostic value of GATA6 expression could be found in oesophageal adenocarcinoma

Ziekenhuis van diagnose beïnvloedt kans op curatieve behandeling voor slokdarm- en maagkanker: Een pleidooi voor regionaa l tumorspeci fiek multidiscip linair overleg

OBJECTIVE: The aim of these studies was to examine the influence of hospital of diagnosis on the probability of receiving curative treatment and its impact on survival among oesophageal and gastric cancer. DESIGN: Although oesophageal and gastric cancer surgery is centralised in the Netherlands, the disease is often diagnosed in hospitals that do not perform this procedure. METHOD: Patients with potentially curable oesophageal or gastric cancer tumours diagnosed between 2005 and 2013 were selected from the Netherlands Cancer Registry. The probability to undergo curative treatment was examined for each hospital of diagnosis after adjustment for case-mix. Effects of variation in probability of undergoing curative treatment among these hospitals on survival were investigated Cox regression. RESULTS: All 13,017 patients with potentially curable oesophageal and 5,620 patients with potentially curable gastric cancer, diagnosed in 91 hospitals, were included. After adjustment, the proportion of oesophageal cancer patients receiving curative treatment ranged from 50% to 82% and from 48% to 78% for patients with gastric cancer in 2010-2013, depending on hospital of diagnosis (both P < 0.001). Furthermore, patients diagnosed in hospitals with a low probability of undergoing curative treatment had a worse overall survival in the period 2010-2013 (oesophageal cancer hazard ratio (HR): 1,15; 95%-CI: 1,07-1,24; gastric cancer HR: 1,21; 95%-CI: 1,04-1,41). CONCLUSION: The variation in probability of undergoing potentially curative treatment for oesophageal and gastric cancer between hospitals of diagnosis and its impact on survival indicates that treatment decision-making for these patients may be improved. Regional expert multidisciplinary team meetings in this field may improve the selection of patients for curative treatment

Esophageal cancer: CT, endoscopie US, and FDG PET for assessment of response to neoadjuvant therapy-systematic review

PURPOSE: To compare diagnostic accuracy of computed tomography (CT), endoscopic ultrasonography (US), and fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for assessment of response to neoadjuvant therapy in patients with esophageal cancer by using a systematic review of the literature. MATERIALS AND METHODS: MEDLINE and EMBASE databases and Cochrane Database of Systematic Reviews were searched for relevant studies. Two reviewers independently assessed the methodological quality of each study. Summary receiver operating characteristic (ROC) analysis was used to summarize and compare the diagnostic accuracy of the three modalities. RESULTS: Four studies with CT, 13 with endoscopic US, and seven with FDC PET met inclusion criteria. Percentages of the maximum score in regard to methodological quality ranged from 15% to 100%. Summary ROC analysis could be performed for three studies with CT, four with endoscopic US, and four with FDG PET. The maximum joint values for sensitivity and specificity were 54% for CT, 86% for endoscopic US, and 85% for FDG PET. Accuracy of CT was significantly lower than that of FDG PET (P < .006) and of endoscopic US (P < .003). Accuracy of FDG PET and that of endoscopic US were similar (P = .839). In all patients, CT was always feasible, whereas endoscopic US was not feasible in 6% of the patients, and FDG PET was not feasible in less than 1%. CONCLUSION: CT has poor accuracy for assessment of response to neoadjuvant therapy in patients with esophageal cancer. Endoscopic US and FDG PET have equivalent good accuracy, but endoscopic US is not always feasible after chemotherapy and radiation therapy. FDG PET seems to be a promising noninvasive tool for assessment of neoadjuvant therapy in patients with esophageal cancer