Virchows Archiv

Ricci, Riccardo; Dei Tos, Angelo; Rindi, Guido

doi: 10.1007/s00428-013-1467-4pmid: 23975171

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. They have represented a paradigm of molecular-targeted therapies for solid tumors since the discovery of KIT mutations and KIT expression in GIST in 1998, which opened the way to the use of imatinib, a tyrosine kinase inhibitor able to inhibit the growth of cells expressing KIT-mutant isoforms. Since then, accumulating evidence revealed the rather heterogeneous nature of GIST, implying possible different diagnostic and therapeutic approaches for each specific case, leading to the development of drugs alternative to imatinib. In this brief commentary, we graphically represent the historical growing of genotype and phenotype evidence on GIST since 1998 in its increasing complexity by building up a graph, which we have called “GISTogram”, that visually conveys most of GIST-characterizing features and the probability for each of them, either alone or in combination, to be observed in a single GIST case.

Lee, Hyoun; Lee, Eun; Kim, Seok-Hyun; Roh, Mee; Jung, Sang; Choi, Young

doi: 10.1007/s00428-013-1461-xpmid: 23913168

Heat shock protein 70 (HSP70) is a molecular chaperone which plays an important role in cellular protection against various stressful stimuli and in the regulation of cellular growth and apoptosis. This study was conducted in gastric carcinoma (GC) to assess correlations of HSP70 expression with clinicopathological parameters and overall survival (OS). Tissue microarray blocks were constructed from 172 GCs and immunohistochemically stained for HSP70. Low HSP70 expression was found in 122 GCs (71 %), whereas 50 (29 %) had high expression. HSP70 expression was higher in tumours in the cardia (p = 0.008), with non-signet ring cell histology (p < 0.001), of intestinal type (p = 0.045) and of higher pathological T stage (p = 0.026). When considering the cohort as a whole, HSP70 expression did not correlate with OS (p = 0.092). In intestinal type carcinomas, however, high HSP70 expression significantly correlated with worse OS (p = 0.034). These results suggest that HSP70 expression might be an unfavourable prognostic factor in patients with GC, especially of intestinal type.

Cobler, Lara; Mejías-Luque, Raquel; Garrido, Marta; Pera, Manuel; Badia-Garrido, Enric; Bolós, Carme

doi: 10.1007/s00428-013-1469-2pmid: 23942618

Trefoil factor 1 (TFF1) is expressed in the normal superficial epithelium of the stomach and is implicated in the maintenance of gastric epithelial structure and function. During gastric carcinogenesis, in which pro-inflammatory cytokines play a crucial role, its expression level decreases suggesting a role as tumor suppressor factor. We have compared expression of TFF1 in gastric mucosa from cancer patients, in which several degrees of inflammatory infiltrate are present, with that in normal mucosa from non-cancer patients without infiltrating inflammatory cells. TFF1 is less expressed in the superficial gastric epithelium from cancer patients than in that from normal individuals in which the nuclear factor (NF)-κB pathway is not activated. We analyzed TFF1 expression in ex vivo samples of gastric mucosa from cancer patients, and in MKN45 gastric cancer cell line after exposure to proinflammatory cytokines interleukin (IL)-1β or tumor necrosis factor (TNF)-α, that activate the NF-κB pathway. We found that IL-1β and TNF-α activate the NF-κB pathway, as reflected in the nuclear expression of p65 and the activation of p-IκBα, and downregulate TFF1 expression after 1 or 2 h of exposure. Moreover, cells in the superficial gastric epithelium in ex vivo samples co-expressed TFF1/p65 at cellular level, whereas tumor cells did not. In summary, downregulation of TFF1 expression during gastric neoplastic transformation is associated with activation of the NF-κB pathway through IL-1β or TNF-α, but other regulatory mechanisms might also be involved.

Neumann, Jens; Wehweck, Laura; Maatz, Susanne; Engel, Jutta; Kirchner, Thomas; Jung, Andreas

doi: 10.1007/s00428-013-1450-0pmid: 23934607

Alterations of the downstream effectors of the epidermal growth factor receptor (EGFR) are common events in colorectal cancer (CRC) carcinogenesis. Since EGFR serves as a target for therapy and some downstream effectors of EGFR have predictive and prognostic impact, reliable information on the frequency and concordance of alterations in the signaling pathway has become clinically significant. We, therefore, determined the frequency and coincidence of mutations in the EGFR pathway. We also analyzed the concordance of these alterations between primary tumor and distant metastases. Furthermore, we assessed their prognostic relevance for the development of metastasis. Mutations of KRAS exon 2, BRAF exons 11 and 15, AKT exon 3, and PIK3CA exons 9 and 20 were analyzed by pyrosequencing in 171 primary CRC samples as well as in 63 corresponding metastases. Furthermore, the expression of PTEN and EGFR was assessed by immunohistochemistry. Of the 171 tumors investigated, 60.2 % showed mutations in one or more genes of pathways downstream of EGFR. KRAS exon 2 and BRAF exon 15 mutations were detected in 40.9 and 11.1 % of cases, respectively, and were mutually exclusive. Mutations in exons 9 and 20 of the PIK3CA gene (18.7 %) largely overlapped with exon 2 KRAS mutations (16 of 32 cases; 50.0 %) and, to a lesser extent, with exon 15 mutations of BRAF (2 of 32 cases; 6.3 %). Only one case had simultaneous mutations of AKT exon 3 (0.6 %) and BRAF exon 15. Mutation analysis for KRAS exon 2, BRAF exon 15, PIK3CA exon 20, and AKT exon 3 in primary tumors and in their corresponding metastases revealed 100 % concordance. In one case, a PIK3CA exon 9 mutation in the primary tumor could not be detected in the matched distant metastases (κ = 0.9). Three different scores were applied for the evaluation of EGFR immunohistochemistry, and the range of positive cases varied between 8.8 and 52.6 %. Loss of PTEN expression was detected in 38.6 %. Although the expression of both markers does coincide with KRAS exon 2, BRAF exon 15, AKT exon 3, and PIK3CA exons 9 and 20 mutations, high discordance rates were found. The presence of at least one alteration in downstream effectors of the EGFR pathway was associated with a higher rate of distant metastases (p = 0.002). PIK3CA exons 9 and 20 mutations overlap with KRAS exon 2 and BRAF exon 15 mutations, and BRAF exon 15 and AKT exon 3 mutations co-occur in a single tumor, whereas KRAS exon 2 and BRAF exon 15 mutations are mutually exclusive. This suggests that mutations in the PIK3CA/PTEN/AKT branch of the EGFR pathway are less important than those of the RAS/RAF/MAPK branch for the progression of CRC. We found no difference in the mutational status of KRAS exon 2, BRAF exon 15, and AKT exon 3 between primary tumor and distant metastasis, validating both for diagnostic purposes. PIK3CA exons 9 and 20 mutations can be discordant between primary tumor and distant metastasis, and therefore, the lesion which is targeted for therapy should be tested. Protein expression of PTEN and EGFR using current protocols yields highly discordant results, and better standardization is needed before these markers can be used for diagnostic purposes.

Matsukuma, Susumu; Kono, Takako; Takeo, Hiroaki; Hamakawa, Yusuke; Sato, Kimiya

doi: 10.1007/s00428-013-1455-8pmid: 23913165

This study examined 47 cases of lung cancer concomitant with other tumors and found eight cases (17 %) with nine foci of tumor-to-tumor metastasis, defined as metastasis of lung cancer into another tumor. Donor lung cancers were four adenocarcinomas, two squamous cell carcinomas, and two small cell carcinomas. Tumor-to-tumor metastasis was found in five of six renal cell carcinomas (83 %), one of eight thyroid papillary carcinomas (13 %), one of three adrenocortical adenomas (33 %), one of three pancreatic endocrine microadenomas (33 %), and another lung cancer (one of six cases of multiple lung cancers, 17 %). The higher recipient incidence in renal cell carcinoma was statistically significant compared with prostatic carcinoma (0/16, P < 0.001), colorectal carcinoma (0/7, P = 0.005), and gastric carcinoma (0/5, P = 0.015). Generalized metastases were found in 88 % of the tumor-to-tumor metastasis cases. The total clinical course of patients with tumor-to-tumor metastasis was shorter than that of the patients without tumor-to-tumor metastasis (mean, 5.4 versus 18.8 months; P = 0.046). Tumor-to-tumor metastasis sometimes mimicked undifferentiated recipient tumor cells. Immunostains for thyroid transcription factor 1 (TTF-1), Napsin A, cytokeratin 7 (CK7), and CK5/6 were useful to confirm tumor-to-tumor metastasis. However, TTF-1-, Napsin A-, and/or CK7-negative lung adenocarcinoma components metastasized to renal cell carcinoma in three cases, and recipient renal cell carcinomas were focally Napsin A+ (two cases) or CK7+ (two cases). Tumor-to-tumor metastasis can occur as a result of metastasis from lung cancer with more aggressive behavior. Tumor-to-tumor metastasis should be carefully distinguished from undifferentiated recipient tumor cells.

McCart Reed, Amy; Song, Sarah; Kutasovic, Jamie; Reid, Lynne; Valle, Jordan; Vargas, Ana; Smart, Chanel; Simpson, Peter

doi: 10.1007/s00428-013-1468-3pmid: 23942617

The thromobospondins are a family of extracellular glycoproteins that are activated during tissue remodeling processes such as embryogenesis, wound healing and cancer. Thrombospondin-4 (THBS4) is known to have roles in cellular migration, adhesion and attachment, as well as proliferation in different contexts. Data to support a role in cancer biology is increasing, including for gastrointestinal and prostate tumours. Here, using a combination of immunohistochemistry, immunofluorescence and analysis of publicly available genomic and expression data, we present the first study describing the pattern of expression of THBS4 in normal breast and breast cancer. THBS4 was located to the basement membrane of large ducts and vessels in normal breast tissue, but was absent from epithelium and extracellular matrix. There was a significant induction in expression in cancer-associated stroma relative to normal stroma (P = 0.0033), neoplastic epithelium (P < 0.0001) and normal epithelium (P < 0.0001). There was no difference in stromal expression of THBS4 between invasive ductal carcinomas (IDC) and invasive lobular carcinomas (ILC). The THBS4 mRNA levels were variable yet were generally highest in tumours typically rich in stromal content (ILC, ER positive low grade IDC; luminal A and normal-like subtypes). Genomic alterations of the THBS4 gene (somatic mutations and gene copy number) are rare suggesting this dramatic activation in expression is most likely dynamically regulated through the interaction between invading tumour cells and stromal fibroblasts in the local microenvironment. In summary, THBS4 expression in breast cancer-associated extracellular matrix contributes to the activated stromal response exhibited during tumour progression and this may facilitate invasion of tumour cells.

Eymerit-Morin, Caroline; Zidane, Merzouka; Lebdai, Souhil; Triau, Stéphane; Azzouzi, Abdel; Rousselet, Marie-Christine

doi: 10.1007/s00428-013-1454-9pmid: 23948957

Low-risk prostate adenocarcinoma is classically managed either with active surveillance or radical therapy (such as external radiotherapy or radical prostatectomy), but both have significant side effects. Vascular-targeted photodynamic therapy (VTP) is a focal therapy proposed as an alternative approach for localized, low-volume, and low-Gleason score (≤6) carcinomas. We report histological modifications observed in prostate biopsies of 56 patients, performed 6 months after VTP using the photosensitizer TOOKAD® Soluble (WST11) and low-energy laser administered in the tumor area transperineally by optic fibers. In 53 patients, we observed sharply demarcated hyaline fibrotic scars, with or without rare atrophic glands, sometimes reduced to corpora amylacea surrounded by giant multinuclear macrophages. Mild chronic inflammation, hemosiderin, and coagulative necrosis were also observed. When residual cancer was present in a treated lobe (17 patients), it was always located outside the scar, most often close to the prostate capsule, and it showed no therapy-related modification. Histopathological interpretation of post-WST11 VTP prostate biopsies was straightforward, in contrast with that of prostate biopsies after radio or hormonal therapy, which introduces lesions difficult to interpret. VTP resulted in complete ablation of cancer in the targeted area.

Fushimi, Fumiyoshi; Taguchi, Kenichi; Izumi, Hiroto; Kohno, Kimitoshi; Kuwano, Michihiko; Ono, Mayumi; Nakashima, Yutaka; Takesue, Tetsuro; Naito, Seiji; Oda, Yoshinao

doi: 10.1007/s00428-013-1460-ypmid: 23907567

Sperga, Maris; Martinek, Petr; Vanecek, Tomas; Grossmann, Petr; Bauleth, Kevin; Perez-Montiel, Delia; Alvarado-Cabrero, Isabel; Nevidovska, Kristine; Lietuvietis, Vilnis; Hora, Milan; Michal, Michal; Petersson, Fredrik; Kuroda, Naoto; Suster, Saul;

Mai, Kien; Flood, Trevor; Williams, Phillip; Kos, Zuzana; Belanger, Eric

doi: 10.1007/s00428-013-1456-7pmid: 23913166

There are two pathways of urothelial carcinogenesis: low-grade urothelial carcinoma (LGUC) with low rates of gene alterations and high-grade urothelial carcinoma (HGUC) with numerous gene alterations. HGUC often displays strong reactivity for cytokeratin 20 (CK20) and p16. Despite distinct molecular changes, urothelial carcinoma (UC) with both low- and high-grade features is not uncommon. We examined cases with patterns of mixed low- and high-grade UC (MLHGUC). Consecutive cases of UC at our institution were reviewed. There were 45 cases that showed a mixture of both LGUC and HGUC. IHC for CK5, CK20, CD44, p16, and Ki67 was performed. Areas of HGUC displayed strong and diffuse reactivity for p16, CK20, and Ki67 in 20–50 % of the tumor, while LGUC areas had negative or focal reactivity for CK20 and Ki67 in 10–30 %. There were two distinct cohorts of MLHGUC: patients with a history of LGUC (group A) and those without (group B). Group A patients (n = 8) had a history of LGUC for 1–10 years. The tumor specimens weighed 1.5 ± 1.7 g and had HGUC components of 25 ± 20 % of the tissue. Superficial invasion was present in one case. All tumors had BCG treatment with one recurrence. In group B (n = 37), tumor specimens weighed 3 ± 3.9 g and had HGUC components in 43 ± 21 % of the tissue. Superficial invasion was present in five cases, and muscle invasion with lung metastasis occurred in one case. Four cases were refractory to BCG with an increased proportion of HGUC, and one case requiring cystectomy. Differences in size and proportion of HGUC between groups A and B MLHGUC were significant (P < 0.05), with group B presenting with a higher tumor burden and proportion of HGUC. MLHGUC is diagnostically challenging and is commonly assigned high grade since this determines prognosis. Group A MLHGUC likely develops as a result of progression from LGUC, whereas group B MLHGUC likely develops de novo, is associated with larger tumors, shows a higher proportion of HGUC, and follows a worse prognosis. Despite the similar histology of groups A and B, assignment to HGUC in a binary system may mask important prognostic information.