Prognostic Role of p53 Immunohistochemical Status in invasive Breast Cancer. A Retrospective Review of 1387 Cases With Luminal-Like/Her2 Negative Breast Tumors.

PURPOSE: The aim of this study was to evaluate the prognostic role of p53 immunohistochemical (IHC) expression in a large cohort of patients with hormone receptors (HR)-positive/Her2-negative primary invasive breast cancer. METHODS: Retrospective review of consecutive cases treated at our Breast Unit between 2003 and 2013. Patients were divided into 3 subgroups based on p53 IHC expression: null (0%), low (0.1%-49%), and high (≥50%) p53 expression. RESULTS: A total of 1387 patients were included in the study with a median follow-up of 86 months. After adjusting for age, size, node status, lymphovascular invasion, progesterone, and Ki67 expression, only null p53 immunophenotype was associated with worse disease-free survival (DFS) (OR 1.74, 95% IC, 1.11-2.71, P = .015) and distant recurrence-free survival (DRFS) (OR 1.73, 95% IC, 1.04-2.90, P = .036). Null p53 impacted significantly DFS and DRFS also in patients with early breast cancer. CONCLUSIONS: p53 IHC expression affects survival and, thus can be a valuable tool in the management of patients with HR-positive/Her2-negative breast cancer.

Fetal Brain Damage in Human Fetuses with Congenital Cytomegalovirus Infection: Histological Features and Viral Tropism.

Human cytomegalovirus (HCMV) causes congenital neurological lifelong disabilities. To date, the neuropathogenesis of brain injury related to congenital HCMV (cCMV) infection is poorly understood. This study evaluates the characteristics and pathogenetic mechanisms of encephalic damage in cCMV infection. Ten HCMV-infected human fetuses at 21 weeks of gestation were examined. Specifically, tissues from different brain areas were analyzed by: (i) immunohistochemistry (IHC) to detect HCMV-infected cell distribution, (ii) hematoxylin-eosin staining to evaluate histological damage and (iii) real-time PCR to quantify tissue viral load (HCMV-DNA). The differentiation stage of HCMV-infected neural/neuronal cells was assessed by double IHC to detect simultaneously HCMV-antigens and neural/neuronal markers: nestin (a marker of neural stem/progenitor cells), doublecortin (DCX, marker of cells committed to the neuronal lineage) and neuronal nuclei (NeuN, identifying mature neurons). HCMV-positive cells and viral DNA were found in the brain of 8/10 (80%) fetuses. For these cases, brain damage was classified as mild (n = 4, 50%), moderate (n = 3, 37.5%) and severe (n = 1, 12.5%) based on presence and frequency of pathological findings (necrosis, microglial nodules, microglial activation, astrocytosis, and vascular changes). The highest median HCMV-DNA level was found in the hippocampus (212 copies/5 ng of human DNA [hDNA], range: 10-7,505) as well as the highest mean HCMV-infected cell value (2.9 cells, range: 0-23), followed by that detected in subventricular zone (1.7 cells, range: 0-19). These findings suggested a preferential viral tropism for both neural stem/progenitor cells and neuronal committed cells, residing in these regions, confirmed by the expression of DCX and nestin in 94% and 63.3% of HCMV-positive cells, respectively. NeuN was not found among HCMV-positive cells and was nearly absent in the brain with severe damage, suggesting HCMV does not infect mature neurons and immature neural/neuronal cells do not differentiate into neurons. This could lead to known structural and functional brain defects from cCMV infection.

Prognostic Role of Mismatch Repair Status, Histotype and High-Risk Pathologic Features in Stage II Small Bowel Adenocarcinomas.

BACKGROUND: Small bowel adenocarcinoma is a relatively rare cancer, often diagnosed in an advanced stage. In localized and resectable disease, surgery alone or in combination with adjuvant chemotherapy is the mainstay of treatment. In the recently published National Comprehensive Cancer Network Clinical Practice guidelines, criteria for selecting patients with stage II small bowel adenocarcinoma to receive adjuvant chemotherapy are provided, and they are mainly extrapolated from studies on colorectal cancer. PATIENTS AND METHODS: In the present study, we aimed to verify whether mismatch repair deficiency phenotype, high-risk pathologic features (including T4, positive resection margins and a low number of lymph nodes harvested), as well as tumor histologic subtype, were associated with cancer-specific survival in 66 stage II non-ampullary small bowel adenocarcinoma patients, collected through the Small Bowel Cancer Italian Consortium. A central histopathology review was performed. Mismatch repair deficiency was tested by immunohistochemistry for MLH1, MSH2, MSH6 and PMS2, and confirmed by polymerase chain reaction for microsatellite instability. RESULTS: We identified mismatch repair deficiency, glandular/medullary histologic subtype, and celiac disease as significant predictors of favorable cancer-specific survival using univariable analysis with retained significance in bivariable models adjusted for pT stage. Among the high-risk features, only T4 showed a significant association with an increased risk of death; however, its prognostic value was not independent of mismatch repair status. CONCLUSIONS: Mismatch repair protein expression, histologic subtype, association with celiac disease, and, in the mismatch repair proficient subset only, T stage, may help identify patients who may benefit from adjuvant chemotherapy.

Morphological Factors Related to Nodal Metastases in Neuroendocrine Tumors of the Appendix: A Multicentric Retrospective Study.

OBJECTIVE: The aim of this study was to evaluate clinical and morphological features related to nodal involvement in appendiceal neuroendocrine tumors (NETs), to identify patients who should be referred for oncological radicalization with hemicolectomy. BACKGROUND: Appendiceal NETs are usually diagnosed accidentally after appendectomy; the indications for right hemicolectomy are currently based on several parameters (ie, tumor size, grading, proliferative index, localization, mesoappendiceal invasion, lymphovascular infiltration). Available guidelines are based on scarce evidence inferred by small, retrospective, single-institution studies, resulting in discordant recommendations. METHODS: A retrospective analysis of a prospectively collected database was performed. Patients who underwent surgical resection of appendiceal NETs at 11 tertiary Italian centers, from January 1990 to December 2015, were included. Clinical and morphological data were analyzed to identify factors related to nodal involvement. RESULTS: Four-hundred fifty-seven patients were evaluated, and 435 were finally included and analyzed. Of them, 21 had nodal involvement. Grading G2 [odds ratio (OR) 6.04], lymphovascular infiltration (OR 10.17), size (OR 18.50), and mesoappendiceal invasion (OR 3.63) were related to nodal disease. Receiver operating characteristic curve identified >15.5 mm as the best size cutoff value (area under the curve 0.747). On multivariate analysis, grading G2 (OR 6.98), lymphovascular infiltration (OR 8.63), and size >15.5 mm (OR 35.28) were independently related to nodal involvement. CONCLUSIONS: Tumor size >15.5 mm, grading G2, and presence of lymphovascular infiltration are factors independently related to nodal metastases in appendiceal NETs. Presence of ≥1 of these features should be considered an indication for oncological radicalization. Although these results represent the largest study currently available, prospective validation is needed.

Sclerosing epithelioid mesenchymal neoplasm of the pancreas - a proposed new entity.

We have encountered pancreatic tumors with unique histologic features, which do not conform to any of the known tumors of the pancreas or other anatomical sites. We aimed to define their clinicopathologic features and whether they are characterized by recurrent molecular signatures. Eight cases were identified; studied histologically and by immunohistochemistry. Selected cases were also subjected to whole-exome sequencing (WES; n = 4), RNA-sequencing (n = 6), Archer FusionPlex assay (n = 5), methylation profiling using the Illumina MethylationEPIC (850k) array platform (n = 6), and TERT promoter sequencing (n = 5). Six neoplasms occurred in females. The mean age was 43 years (range: 26-75). Five occurred in the head/neck of the pancreas. All patients were treated surgically; none received neoadjuvant/adjuvant therapy. All patients are free of disease after 53 months of median follow-up (range: 8-94). The tumors were well-circumscribed, and the median size was 1.8 cm (range: 1.3-5.8). Microscopically, the unencapsulated tumors had a geographic pattern of epithelioid cell nests alternating with spindle cell fascicles. Some areas showed dense fibrosis, in which enmeshed tumor cells imparted a slit-like pattern. The predominant epithelioid cells had scant cytoplasm and round-oval nuclei with open chromatin. The spindle cells displayed irregular, hyperchromatic nuclei. Mitoses were rare. No lymph node metastases were identified. All tumors were positive for vimentin, CD99 and cytokeratin (patchy), while negative for markers of solid pseudopapillary neoplasm, neuroendocrine, acinar, myogenic/rhabdoid, vascular, melanocytic, or lymphoid differentiation, gastrointestinal stromal tumor as well as MUC4. Whole-exome sequencing revealed no recurrent somatic mutations or amplifications/homozygous deletions in any known oncogenes or tumor suppressor genes. RNA-sequencing and the Archer FusionPlex assay did not detect any recurrent likely pathogenic gene fusions. Single sample gene set enrichment analysis revealed that these tumors display a likely mesenchymal transcriptomic program. Unsupervised analysis (t-SNE) of their methylation profiles against a set of different mesenchymal neoplasms demonstrated a distinct methylation pattern. Here, we describe pancreatic neoplasms with unique morphologic/immunophenotypic features and a distinct methylation pattern, along with a lack of abnormalities in any of key genetic drivers, supporting that these neoplasms represent a novel entity with an indolent clinical course. Given their mesenchymal transcriptomic features, we propose the designation of "sclerosing epithelioid mesenchymal neoplasm" of the pancreas.

Correction: PD-L1 in small bowel adenocarcinoma is associated with etiology and tumor-infiltrating lymphocytes, in addition to microsatellite instability.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

PD-L1 in small bowel adenocarcinoma is associated with etiology and tumor-infiltrating lymphocytes, in addition to microsatellite instability.

Small bowel adenocarcinomas (SBAs) are often associated with poor prognosis and have limited therapeutic options. Programmed cell death protein-1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway blockade is an effective treatment in many microsatellite instability-high (MSI-H) solid tumors. We aimed at investigating PD-L1 and PD-1 expression in non-hereditary, non-ampullary SBAs, associated with celiac disease (CeD), Crohn's disease (CrD), or sporadic, recruited through the Small Bowel Cancer Italian Consortium. We assessed PD-L1 and PD-1 by immunohistochemistry in a series of 121 surgically resected SBAs, including 34 CeD-SBAs, 49 CrD-SBAs, and 38 sporadic SBAs. PD-L1 and PD-1 expression was correlated with several clinico-pathological features, such as the etiology, microsatellite instability status, and tumor-infiltrating lymphocyte (TIL) density. The prevalence of PD-L1 positivity according to combined positive score (CPS) was 26% in the whole cohort of SBAs, with significantly (p = 0.001) higher percentage (35%) in both CeD-SBAs and CrD-SBAs in comparison with sporadic SBAs (5%). CPS ≥ 1 SBAs were significantly (p = 0.013) more frequent in MSI-H cases (41%) than in non-MSI-H ones (18%); however, 15 CPS ≥ 1 microsatellite stable SBAs were also identified. CPS ≥ 1 SBAs showed higher TIL and PD-1+ immune cell density, more frequently medullary histotype, as well as a better outcome in comparison with CPS < 1 cases. This study demonstrates an increased proportion of PD-L1+ cases in both CeD-SBAs and CrD-SBAs in comparison with sporadic SBAs. In addition, the identification of a subset of PD-L1+ microsatellite stable SBAs supports the need to ascertain additional biomarkers of response to immune checkpoint inhibitors along with MSI-H.

An Analysis of Clinical, Surgical, Pathological and Molecular Characteristics of Endometrial Cancer According to Mismatch Repair Status. A Multidisciplinary Approach.

Since 2016, our hospital has applied tumor testing with immunohistochemistry (IHC) in endometrial cancer in order to detect mutations of mismatch repair genes (MMR). All cases with MMR deficiency proteins expression are sent for genetic testing, except those with MLH1 protein deficiency, in which case genetic testing is performed if negative for promoter hypermethylation. The primary aim of this study was to investigate the ability of our algorithm to identify Lynch syndrome (LS). The Secondary aims were to investigate the relationship between MMR status and clinicopathological features and prognosis of primary endometrial cancer (EC). From January 2016 to December 2018, 239 patients with EC were retrospectively analyzed and subdivided according to MMR status. Patients were divided in three groups: MMR proficient, LS and Lynch-like cancer (LLC). LS was characterized by a lower age and BMI, more use of contraceptive and less use of hormonal replacement therapy, nulliparity and a trend versus a better prognosis. LLC appeared more related to MMR proficient than LS and exhibited a more aggressive behavior. Our multidisciplinary approach permitted a correct diagnosis of germline mutation in patients with newly diagnosis EC and it confirmed clinicopathologic and prognostic characteristics of LS.

Gain of FGF4 is a frequent event in KIT/PDGFRA/SDH/RAS-P WT GIST.

Gastrointestinal stromal tumors (GIST) lacking mutations in KIT/PDGFRA or RAS pathways and retaining an intact SDH complex are usually referred to as KIT/PDGFRA/SDH/RAS-P WT GIST or more simply quadruple WT GIST (~5% of all GIST). Despite efforts made, no recurrent genetic event in quadruple WT GIST has been identified so far. To further investigate this disease, we performed high throughput copy number analysis on quadruple WT GIST specimens identifying a recurrent focal gain in band 11q13.3 (involving FGF3/FGF4) in 6/8 cases. This event was not found in the other molecular GIST subgroups. FGF3/FGF4 duplication was associated with high expression of FGF4, both at mRNA and protein level, a growth factor normally not expressed in adult tissues or in KIT/PDGFRA-mutated GIST. FGFR1 was found to be the predominant FGF receptor expressed and phosphorylation of AKT was detected, suggesting that a FGF4-FGFR1 autocrine loop could stimulate downstream signaling in quadruple WT GIST. Together with the recent reports of quadruple WT cases carrying FGFR1 activating alterations, these findings strengthen the hypothesis of a potential involvement of FGFR pathway deregulation in quadruple WT GIST, which may represent a rationale for novel therapeutic approaches.

Unusual bilateral ovarian metastases from ileal gastrointestinal stromal tumor (GIST): a case report.

BACKGROUND: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract and liver and peritoneum are the main sites of recurrence. Ovarian metastases from GIST are very rare. CASE PRESENTATION: A 50 years-old woman was found to have a pelvic mass on transvaginal ultrasound (TV-US) and computed tomography (CT)-scan, considered as a right ovarian mass. The patient underwent surgical abdominal exploration that showed an ileal mass, a normal right ovary and an irregular and vascularized surface of the left ovary. A segmental ileal resection and an ileal anastomosis were performed. Frozen section showed a GIST and surgery was completed with hysterectomy, bilateral salpingo-oophorectomy, pelvic peritonectomy, peritoneal washing and Burch procedure. The histological examination confirmed an ileal GIST with ovarian metastases, harboring in both sites of disease a KIT exon 11 deletion. CONCLUSIONS: Ovarian localizations, as far as rare, can be a clinical finding in case of ileal GIST patients, and both gynecologists, pathologists and medical oncologists should be able to recognize them.

Pathological and molecular diagnosis of bilateral inguinal lymph nodes metastases from low-grade endometrial adenocarcinoma: a case report with review of the literature.

BACKGROUND: Extra-abdominal metastases in low grade endometrial carcinoma are rare events. Inguinal lymphatic spread occurs usually in advanced disease and is associated with abdominal lymph nodes involvement. To our knowledge, isolated inguinal lymph node metastases in patients with early endometrial carcinoma have never been described thus far. CASE PRESENTATION: We present an uncommon case of inguinal lymph node metastasis in a 51-year old patient with early endometrial disease without other metastatic involvement. The metastatic loci were analyzed with the recently validated method of mitochondrial DNA sequencing to demonstrate clonality of the lesions. CONCLUSIONS: We describe the first case of inguinal metastasis from intramucous endometrial carcinoma; this case confirms the unpredictable spread of endometrial neoplasia and the importance of both patient's history and physical examination in good clinical practice.

Is radical surgery always curative in pancreatic neuroendocrine tumors? A cure model survival analysis.

BACKGROUND: Adjuvant therapy after curative surgery for sporadic pancreatic neuroendocrine tumor (pNETs) is not currently recommended, assuming that all patients could be cured by a radical resection. The aim of our study is to establish how many and which kind of patients remained uncured after radical resection of pNET. METHODS: Retrospective study involving 143 resected sporadic pNETs. The survival analysis was carried out using the cure model, describing the cure fraction and the excess of risk recurrence. Multivariate analyses were made in order to evaluate the non negligible effect of demographics, clinical and pathological factors on survival parameters. The results were reported as percentages, fractions, ORs and HRs with 95% confidence interval (95 CI %). RESULTS: The cure fraction and the excess of hazard rate of the whole population were 57.1% (37.4-74.6, 95% CI) and 0.06 (0.03-0.07, 95% CI), respectively. Two independent factors were related to the cure fraction: TNM stage (OR 0.27 ±â€¯0.17; P = 0.002) and grading (OR 0.11 ±â€¯0.18; P = 0.004). Considering the excess of hazard rate, only two independent factors were related to an increased risk of recurrence: TNM stage (HR 3.49 ±â€¯1.12; P = 0.004) and grading (HR 4.93 ±â€¯1.82; P < 0.001). CONCLUSION: The radical surgery has a high probability of cure in stages I-II or in grading 1 while, in stages III-IV or in grading 3 tumors, surgery alone failed to achieve a "cure". A multimodal treatment should be employed in order to avoid a recurrence of the disease.

Integrated Molecular Characterization of Gastrointestinal Stromal Tumors (GIST) Harboring the Rare D842V Mutation in PDGFRA Gene.

Gastrointestinal stromal tumors (GIST) carrying the D842V activating mutation in the platelet-derived growth factor receptor alpha (PDGFRA) gene are a very rare subgroup of GIST (about 10%) known to be resistant to conventional tyrosine kinase inhibitors (TKIs) and to show an indolent behavior. In this study, we performed an integrated molecular characterization of D842V mutant GIST by whole-transcriptome and whole-exome sequencing coupled with protein-ligand interaction modelling to identify the molecular signature and any additional recurrent genomic event related to their clinical course. We found a very specific gene expression profile of D842V mutant tumors showing the activation of G-protein-coupled receptor (GPCR) signaling and a relative downregulation of cell cycle processes. Beyond D842V, no recurrently mutated genes were found in our cohort. Nevertheless, many private, clinically relevant alterations were found in each tumor (TP53, IDH1, FBXW7, SDH-complex). Molecular modeling of PDGFRA D842V suggests that the mutant protein binds imatinib with lower affinity with respect to wild-type structure, showing higher stability during the interaction with other type I TKIs (like crenolanib). D842V mutant GIST do not show any actionable recurrent molecular events of therapeutic significance, therefore this study supports the rationale of novel TKIs development that are currently being evaluated in clinical studies for the treatment of D842V mutant GIST.

Mitochondrial DNA sequencing demonstrates clonality of peritoneal implants of borderline ovarian tumors.

Borderline ovarian tumors are rare low malignant potential neoplasms characterized by the absence of stromal invasion, whose main prognostic factors are stage and type of peritoneal implants. The latter are defined as invasive when cell proliferation invades the underlying tissue (peritoneal surface, omentum and intestinal wall), or noninvasive. It is still unknown if these implants are metastatic spread from the primary ovarian mass or a neoplastic transformation de novo of the peritoneal surface. Mitochondrial DNA sequencing was performed to assess clonality in eight patients presenting both borderline ovarian tumors and implants. In 37.5% of the cases, the same mitochondrial DNA mutation was present in both borderline ovarian tumors and the peritoneal implant, being this evidence that implants may arise as a consequence of a spread from a single ovarian site.

Salivary glands and human congenital cytomegalovirus infection: What happens in early fetal life?

Salivary glands are a site of human cytomegalovirus (CMV) replication, latency, and persistence. Prolonged secretion of virus in saliva for months following a primary infection contribute to horizontal transmission. In order to better understand the early effects of CMV on salivary glands and the mechanisms of viral persistent replication, submandibular glands of six CMV congenitally infected fetuses at 21 weeks gestation were studied. Three fetuses at the same gestational age from CMV-seronegative women were compared as negative controls. Tissue viral load and the type of inflammatory infiltrate were evaluated. Moreover, development and branching of salivary glands, the number of myoepithelial cells, cellular proliferation, and expression of secretory proteins of the saliva (Gross Cystic Disease Fluid Protein-15 and lysozyme) were studied. A low viral load and rare CMV-positive cells associated with T CD8 cytotoxic lymphocytes were observed. Branching was impaired with a decrease in terminal acinar structures, the number of myoepithelial cells, and cellular proliferation were reduced. In addition, a compromised secretion of defense proteins involved in the oral humoral immunity was observed. These findings suggest that CMV may affect salivary glands, impairing structure development and secretion of defense proteins, probably responsible for the prolonged viral shedding in saliva. J. Med. Virol. 89:318-323, 2017. © 2016 Wiley Periodicals, Inc.

Is surgery the best treatment for sporadic small (≤2 cm) non-functioning pancreatic neuroendocrine tumours? A single centre experience.

BACKGOUND: There is currently there is substantial controversy regarding the best management of non-functioning pancreatic neuroendocrine tumours ≤2 cm. METHODS: Retrospective study involving 102 surgically treated patients affected by non-functioning pancreatic neuroendocrine tumours. Patients having small tumours (≤2 cm) (Group A) and those having large tumours (>2 cm) (Group B) were compared regarding demographics, clinical and pathological factors with the aim of evaluating the risk of malignancy and survival times. RESULTS: The small tumours were T3-4 in 11% and G2-3 in 36.6% of cases; lymph node and distant metastases were present in 31% and 8% of the cases, respectively. When small and large tumours were compared, significant differences were found in relation to the presence of symptoms (P = 0.012), tumour status (P > 0.001), grading (P > 0.001) and years lost due to disability (P = 0.002). Multivariate analysis of the factors predicting malignancy and survival times showed that tumour size was related only to grading (P < 0.001). The years of life lost and disability adjusted life years were influenced by age at of diagnosis, the presence of symptoms and years lost due to disability only by grading. CONCLUSIONS: Tumour size alone did not seem to be reliable in predicting malignancy because, first, small tumours (≤2 cm) could present lymph node or distant metastases, and could be G2-3 in a non-negligible percentage of cases and second, their risk of malignancy and survival time are similar to large tumours. Additional parameters have to be considered in order to establish the proper management of small tumours, such as age at diagnosis, presence of symptoms and grading.

Validation of the 2010 WHO classification and a new prognostic proposal: A single centre retrospective study of well-differentiated pancreatic neuroendocrine tumours.

BACKGOUND: In 2010, the World Health Organization (WHO) modified the classification for pancreatic neuroendocrine tumours (NETs). Recently, some modifications were proposed to improve its prognostic value. The aim of this study was to test the prognostic value of both the original and the modified 2010 WHO grading systems. METHODS: One hundred and twenty consecutive patients surgically resected for well-differentiated NETs were evaluated in multivariate Cox regression models. Age, sex, hormonal status, size, lymph node ratio, stage, margin status and grading were evaluated in order to predict disease-free survival (DFS). Four models were evaluated: model 1: grading according to the 2010 WHO; model 2: modified grading with cut-off at 5% of the Ki-67 index; model 3: modified grading in which the G2 category was divided into two subgroups (2-5% and 5-20%) and model 4: the Ki-67 index as a continuous variable. Decision curve analysis (DCA) was carried out to evaluate the clinical utility of the various cut-offs. RESULTS: All the grading systems remained independent factors in predicting DFS. Model 2 (c index = 0.814 and P = 0.012) and model 3 (c index = 0.865 and P = 0.015) showed higher predictive powers with respect to model 1 (c index = 0.799). Model 4 had a high predictive value (c index 0.848, P = 0.013). Decision curve analysis confirmed that biological behaviour represented the best prognostic parameter. CONCLUSION: This study presented some limitations: single centre, retrospective design and a long period of enrolment. The result showed that, by increasing the cut-off of the G2 category to 5% or by creating two subgroups in the G2 category, it was possible to obtain a better stratification of patients.

Successful treatment with personalized dosage of imatinib in elderly patients with gastrointestinal stromal tumors.

Imatinib is the standard first-line therapy for metastatic gastrointestinal stromal tumors. It has markedly improved the prognosis and outcome of patients affected by gastrointestinal stromal tumors, especially in the case of exon 11 KIT mutations. Imatinib-associated adverse events are generally mild to moderate; however, in clinical practice, intolerance caused by chronic toxicities frequently leads to breaks in treatment. This is particularly true in elderly patients in whom age, decline in drug metabolism, and polypharmacy, with a possible drug-drug interaction, may influence the tolerability of imatinib. In the present article, we report our extensive experience with the management of imatinib therapy in a 'real' population, in particular in very elderly patients, discussing whether the use of personalized imatinib dosage could be a safe and advantageous option, enabling continuous administration, thus ensuring effective treatment. Only a few case reports in the literature provide data on outcome with low tailored dosage of imatinib and none of them has been carried out on a Western population. Here, we report four cases treated with low imatinib dosage as a safe and useful option enabling continued treatment with imatinib, improving tolerance, and maintaining good and lasting disease control.

Whole exome sequencing (WES) on formalin-fixed, paraffin-embedded (FFPE) tumor tissue in gastrointestinal stromal tumors (GIST).

BACKGROUND: Next generation sequencing (NGS) technology has been rapidly introduced into basic and translational research in oncology, but the reduced availability of fresh frozen (FF) tumor tissues and the poor quality of DNA extracted from formalin-fixed, paraffin-embedded (FFPE) has significantly impaired this process in the field of solid tumors. To evaluate if data generated from FFPE material can be reliably produced and potentially used in routine clinical settings, we performed whole exome sequencing (WES) from tumor samples of Gastrointestinal stromal tumors (GIST), either extracted FF or FFPE, and from matched normal DNA. METHODS: We performed whole exome enrichment and sequencing at 100bp in paired end on four GIST samples, either from FFPE or fresh-frozen tissue, and from matched normal DNA. RESULTS: The integrity of DNA extracted from FFPE was evaluated by a modified RAPD PCR method, thus identifying high quality (HQ) and low quality (LQ) FFPE. DNA library production and exome capture was feasible for both classes of FFPE, despite the smaller yield and insert size of LQ-FFPE. WES produced data of equal quality from FF and FFPE, while only HQ-FFPE yielded an amount of data comparable to FF samples. Bioinformatic analysis showed that the percentage of variants called both in FF and FFPE samples was very high in HQ-FFPE, reaching 94-96 % of the total number of called variants. Classification of somatic variants by nucleotide substitution type showed that HQ-FFPE and FF had similar mutational profiles, while LQ-FFPE samples carried a much higher number of mutations than the FF counterpart, with a significant enrichment of C > T/G > A substitutions. Focusing on potential disease-related variants allowed the discovery of additional somatic variants in GIST samples, apart from the known oncogenic driver mutation, both from sequencing of FF and FFPE material. False positive and false negative calls were present almost exclusively in the analysis of FFPE of low quality. On the whole this study showed that WES is feasible also on FFPE specimens and that it is possible to easily select FFPE samples of high quality that yield sequencing results comparable to the FF counterpart. CONCLUSIONS: WES on FFPE material may represent an important and innovative source for GIST research and for other solid tumors, amenable of possible application in clinical practice.

JHDM1B expression regulates ribosome biogenesis and cancer cell growth in a p53 dependent manner.

Tumors characterized by an intense ribosome biogenesis often display a more aggressive behavior. Ribosomal RNA (rRNA) synthesis is controlled at several levels, including the epigenetic regulation of the condensation of chromatin portions containing rRNA genes. JHDM1B (Jumonji C histone demethylase 1B) is a histone demethylase able to regulate the accessibility of rRNA genes. In this study, we aimed to define the contribution of JHDM1B expression to the features of breast cancer, a tumor type whose behavior is related to the rate of ribosome biogenesis. We show that, in breast cancer-derived cell lines, the increase in rRNA transcription that follows JHDM1B knock-down is mirrored by an augmented cell proliferation only in p53 compromised cells, while p53 competent cells undergo cellular senescence and death. The latter effect appears to be mediated by a p38-dependent phosphorylation of p53, inducing the expression of p15(Ink4b) and p21(Waf1). In breast cancers, lower JHDM1B expression correlates with an increased size of specifically stained nucleolar organized regions, a morphological parameter directly related to the rate of ribosome biogenesis and with a poorer prognosis. In addition, in tumors lacking the controller function of p53, a lower expression of JHDM1B is associated with an increased tumor size at diagnosis. Altogether, our data indicate that epigenetic activation of rDNA genes induced by JHDM1B depletion is associated with a p53-dependent growth arrest, but may promote cancer cell growth when p53 is lacking.