The 5-year survival rate after complete resection of GISTs is approximately 50 per cent. The median duration of survival for patients with a metastatic GIST is approximately 20 months, and 9-12 months for patients with local recurrence. Phase II trials have investigated the effect of imatinib on irresectable or metastatic GISTs. In these trials more than 50 per cent of patients responded to imatinib within a few months and approximately 12 per cent had disease progression. Uptake of [(18)F]fluoro-2-deoxy-D-glucose demonstrated by positron emission tomography has been found to be reduced after starting imatinib. The potential for cure and the optimal length of treatment is currently unknown. Imatinib is the first effective systemic therapy for metastatic and locally irresectable GISTs. Large multi-institutional clinical trials to investigate the efficacy of imatinib as adjuvant or neoadjuvant therapy for GISTs are now required.

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Little quantitative data exist on the extent of apoptosis (genetically-mediated cell deletion) in different human tumor types. Hematoxylin and eosin-stained paraffin sections of 102 malignant tumors (58 types) were evaluated for apoptotic cells and apoptotic bodies, using the 40x objective with a calibrated eye-piece and avoiding necrotic zones. The percentage of apoptotic cells and apoptotic bodies in the total number of tumor cells examined was designated as the apoptotic index (AI) for each case. There was a wide range in the AI for different tumor types: 45 tumors had AI < 1% and 93 had an AI of < 7%. In 107 additional tumors (11 types), the AI was determined to be within the same low, intermediate, or high range as the index cases. Apoptotic nuclear material was usually more prominent than mitoses. These results suggest that each tumor type has a characteristic AI that reflects innate tumor cell susceptibility to undergo apoptosis. Additional data are needed to determine whether significant variations in AI correlate with altered proliferative indices, aberrant oncogene/tumor suppressor gene expression, and standard clinicopathologic variables.

The decision to use 10% neutral buffered formalin fixed, paraffin embedded (FFPE) archival pathology material may be dictated by the cancer research question or analytical technique, or may be governed by national ethical, legal and social implications (ELSI), biobank, and sample availability and access policy. Biobanked samples of common tumors are likely to be available, but not all samples will be annotated with treatment and outcomes data and this may limit their application. Tumors that are rare or very small exist mostly in FFPE pathology archives. Pathology departments worldwide contain millions of FFPE archival samples, but there are challenges to availability. Pathology departments lack resources for retrieving materials for research or for having pathologists select precise areas in paraffin blocks, a critical quality control step. When samples must be sourced from several pathology departments, different fixation and tissue processing approaches create variability in quality. Researchers must decide what sample quality and quality tolerance fit their specific purpose and whether sample enrichment is required. Recent publications report variable success with techniques modified to examine all common species of molecular targets in FFPE samples. Rigorous quality management may be particularly important in sample preparation for next generation sequencing and for optimizing the quality of extracted proteins for proteomics studies. Unpredictable failures, including unpublished ones, likely are related to pre-analytical factors, unstable molecular targets, biological and clinical sampling factors associated with specific tissue types or suboptimal quality management of pathology archives. Reproducible results depend on adherence to pre-analytical phase standards for molecular in vitro diagnostic analyses for DNA, RNA and in particular, extracted proteins. With continuing adaptations of techniques for application to FFPE, the potential to acquire much larger numbers of FFPE samples and the greater convenience of using FFPE in assays for precision medicine, the choice of material in the future will become increasingly biased toward FFPE samples from pathology archives. Recognition that FFPE samples may harbor greater variation in quality than frozen samples for several reasons, including variations in fixation and tissue processing, requires that FFPE results be validated provided a cohort of frozen tissue samples is available.

Both coumarin (1,2-benzopyrone) and warfarin (4-hydroxycoumarin) have been shown to prevent the recurrence of malignant melanoma. Their action is macrophage-dependent and the dosage is critical. In 1984 a multicentre, prospective, randomised, double-blind trial of coumarin, given as a daily 50-mg dose for 2 years after surgery in patients with high-risk melanoma, was started. the patients had lesions greater than 1.70 mm thick and TNM stage IB or stage II disease. To date there are 4 recurrences in the coumarin-treated group of 13 patients, and 10 recurrences in the placebo-treated group of 14 patients (P < 0.01). There were no toxic effects.

BackgroundThere is an urgent need to measure phosphorylated cell signaling proteins in cancer tissue for the individualization of molecular targeted kinase inhibitor therapy. However, phosphoproteins fluctuate rapidly following tissue procurement. Snap-freezing preserves phosphoproteins, but is unavailable in most clinics and compromises diagnostic morphology. Formalin fixation preserves tissue histomorphology, but penetrates tissue slowly, and is unsuitable for stabilizing phosphoproteins. We originated and evaluated a novel one-step biomarker and histology preservative (BHP) chemistry that stabilizes signaling protein phosphorylation and retains formalin-like tissue histomorphology with equivalent immunohistochemistry in a single paraffin block.ResultsTotal protein yield extracted from BHP-fixed, routine paraffin-embedded mouse liver was 100% compared to snap-frozen tissue. The abundance of 14 phosphorylated proteins was found to be stable over extended fixation times in BHP fixed paraffin embedded human colon mucosa. Compared to matched snap-frozen tissue, 8 phosphoproteins were equally preserved in mouse liver, while AMPKβ1 Ser108 was slightly elevated after BHP fixation. More than 25 tissues from mouse, cat and human specimens were evaluated for preservation of histomorphology. Selected tissues were evaluated in a multi-site, independent pathology review. Tissue fixed with BHP showed equivalent preservation of cytoplasmic and membrane cytomorphology, with significantly better nuclear chromatin preservation by BHP compared to formalin. Immunohistochemical staining of 13 non-phosphorylated proteins, including estrogen receptor alpha, progesterone receptor, Ki-67 and Her2, was equal to or stronger in BHP compared to formalin. BHP demonstrated significantly improved immunohistochemical detection of phosphorylated proteins ERK Thr202/Tyr204, GSK3-α/β Ser21/Ser9, p38-MAPK Thr180/Tyr182, eIF4G Ser1108 and Acetyl-CoA Carboxylase Ser79.ConclusionIn a single paraffin block BHP preserved the phosphorylation state of several signaling proteins at a level comparable to snap-freezing, while maintaining the full diagnostic immunohistochemical and histomorphologic detail of formalin fixation. This new tissue fixative has the potential to greatly facilitate personalized medicine, biobanking, and phospho-proteomic research.

The objective of this study was twofold: (1) to determine if a cellular digestion process can facilitate examination of the morphology of the connective tissue framework of the prostate, and (2) to examine the connective tissue framework in normal prostate tissue, benign prostatic hyperplasia (BPH) and prostate cancer. Ten prostate glands were examined. Using the Ohtani method of digestion, the cellular elements were removed. This enabled scanning electron microscopy analysis of the connective tissue framework within the prostatic tissue. Light microscopy of tissue blocks determined the histology of specimens. The prostate is supported by a highly structured network of collagen fibres. This network of fibres varies in normal and diseased states. In benign prostatic hyperplasia, the collagen network is dense, with an increased number of fibres. In prostatic adenocarcinoma, there is non-uniform swelling with a loss and disintegration of collagen fibres. In conclusion, sodium hydroxide cellular digestion provides an excellent method for demonstrating the connective tissue framework of prostatic tissue. The morphological changes in collagen fibres in normal prostate, benign prostatic hyperplasia and prostatic adenocarcinoma have implications for prostate growth in normal and diseased states.

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