The proliferative activity of breast tumors, which is routinely estimated by counting of mitotic figures in hematoxylin and eosin stained histology sections, is considered to be one of the most important prognostic markers. However, mitosis counting is laborious, subjective and may suffer from low inter-observer agreement. With the wider acceptance of whole slide images in pathology labs, automatic image analysis has been proposed as a potential solution for these issues. In this paper, the results from the Assessment of Mitosis Detection Algorithms 2013 (AMIDA13) challenge are described. The challenge was based on a data set consisting of 12 training and 11 testing subjects, with more than one thousand annotated mitotic figures by multiple observers. Short descriptions and results from the evaluation of eleven methods are presented. The top performing method has an error rate that is comparable to the inter-observer agreement among pathologists.

SUMMARY Whipple's disease is a rare infectious disease that can be fatal if left untreated. The disease is caused by infection with Tropheryma whipplei, a bacterium that may be more common than was initially assumed. Most patients present with nonspecific symptoms, and as routine cultivation of the bacterium is not feasible, it is difficult to diagnose this infection. On the other hand, due to the generic symptoms, infection with this bacterium is actually quite often in the differential diagnosis. The gold standard for diagnosis used to be periodic acid-Schiff (PAS) staining of duodenal biopsy specimens, but PAS staining has a poor specificity and sensitivity. The development of molecular techniques has resulted in more convenient methods for detecting T. whipplei infections, and this has greatly improved the diagnosis of this often missed infection. In addition, the molecular detection of T. whipplei has resulted in an increase in knowledge about its pathogenicity, and this review gives an overview of the new insights in epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of Tropheryma whipplei infections.

BackgroundFor gastric cancer patients, surgical resection with en-bloc lymphadenectomy is the cornerstone of curative treatment. Open gastrectomy has long been the preferred surgical approach worldwide. However, this procedure is associated with considerable morbidity. Several meta-analyses have shown an advantage in short-term outcomes of laparoscopic gastrectomy compared to open procedures, with similar oncologic outcomes. However, it remains unclear whether the results of these Asian studies can be extrapolated to the Western population. In this trial from the Netherlands, patients with resectable gastric cancer will be randomized to laparoscopic or open gastrectomy.MethodsThe study is a non-blinded, multicenter, prospectively randomized controlled superiority trial. Patients (≥18 years) with histologically proven, surgically resectable (cT1-4a, N0-3b, M0) gastric adenocarcinoma and European Clinical Oncology Group performance status 0, 1 or 2 are eligible to participate in the study after obtaining informed consent. Patients (n = 210) will be included in one of the ten participating Dutch centers and are randomized to either laparoscopic or open gastrectomy. The primary outcome is postoperative hospital stay (days). Secondary outcome parameters include postoperative morbidity and mortality, oncologic outcomes, readmissions, quality of life and cost-effectiveness.DiscussionIn this randomized controlled trial laparoscopic and open gastrectomy are compared in patients with resectable gastric cancer. It is expected that laparoscopic gastrectomy will result in a faster recovery of the patient and a shorter hospital stay. Secondly, it is expected that laparoscopic gastrectomy will be associated with a lower postoperative morbidity, less readmissions, higher cost-effectiveness, better postoperative quality of life, but with similar mortality and oncologic outcomes, compared to open gastrectomy. The study started on 1 December 2014. Inclusion and follow-up will take 3 and 5 years respectively. Short-term results will be analyzed and published after discharge of the last randomized patient.Trial registration NCT02248519

Background Patients with peritoneal metastases from colorectal cancer have a poor prognosis. If the intraperitoneal tumour load is limited, patients may be eligible for cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC). This treatment has improved overall survival, but recurrence rates are high. The aim of this study was to create a preclinical platform for the development of more effective intraperitoneal chemotherapy strategies. Methods Using organoid technology, five tumour cultures were generated from malignant ascites and resected peritoneal metastases. These were used in an in vitro HIPEC model to assess sensitivity to mitomycin C (MMC) and oxaliplatin, the drugs used most commonly in HIPEC. The model was also used to test a rational combination treatment involving MMC and inhibitors of the checkpoint kinase ATR. Results MMC was more effective in eliminating peritoneal metastasis‐derived organoids than oxaliplatin at clinically relevant concentrations. However, the drug concentrations required to eliminate 50 per cent of the tumour cells (IC50) were higher than the median clinical dose in two of five organoid lines for MMC, and all five lines for oxaliplatin, indicating a general resistance to monotherapy. ATR inhibition increased the sensitivity of all peritoneal metastasis‐derived organoids to MMC, as the IC50 decreased 2·6–12·4‐fold to well below concentrations commonly attained in clinical practice. Live‐cell imaging and flow cytometric analysis showed that ATR inhibition did not release cells from MMC‐induced cell cycle arrest, but caused increased replication stress and accelerated cell death. Conclusion Peritoneal metastasis‐derived organoids can be used to evaluate existing HIPEC regimens on an individual‐patient level and for development of more effective treatment strategies. Cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC) has improved prognosis of patients with peritoneal metastases from colorectal cancer, but disease recurrence is common. More effective and personalized HIPEC is urgently needed. Organoid technology is frequently used for drug screens, as patient‐derived organoids can accurately predict clinical therapeutic response in vitro.A panel of organoids was established from peritoneal metastases from colorectal cancer and used to develop a model for testing HIPEC regimens in vitro. Patient‐derived organoids differed in sensitivity to commonly used chemotherapeutics, in line with variable clinical outcomes following cytoreductive surgery–HIPEC. Combining MMC with an ATR inhibitor improved the efficacy of MMC.Peritoneal metastasis‐derived organoids can be used as a platform to test novel (combination) strategies that increase HIPEC efficacy. In the future, organoids could be used to select patent‐tailored HIPEC regimens.

Our data do not support an increased risk of LNM or recurrence after secondary surgery compared with primary surgery. Therefore, an attempt for an en-bloc resection of a possible T1 CRC without evident signs of deep invasion seems justified in order to prevent surgery of low-risk T1 CRC in a significant proportion of patients.