REGISTRI: Regorafenib in first-line of KIT/PDGFRA wild type metastatic GIST: a collaborative Spanish (GEIS), Italian (ISG) and French Sarcoma Group (FSG) phase II trial.

BACKGROUND: Approximately 15% of adult GIST patients harbor tumors that are wild-type for KIT and PDGFRα genes (KP-wtGIST). These tumors usually have SDH deficiencies, exhibit a more indolent behavior and are resistant to imatinib. Underlying oncogenic mechanisms in KP-wtGIST include overexpression of HIF1α high IGFR signaling through the MAPK pathway or BRAF activating mutation, among others. As regorafenib inhibits these signaling pathways, it was hypothesized that it could be more active as upfront therapy in advanced KP-wtGIST. METHODS: Adult patients with advanced KP-wtGIST after central confirmation by NGS, naïve of systemic treatment for advanced disease, were included in this international phase II trial. Eligible patients received regorafenib 160 mg per day for 21 days every 28 days. The primary endpoint was disease control rate (DCR), according to RECIST 1.1 at 12 weeks by central radiological assessment. RESULTS: From May 2016 to October 2020, 30 patients were identified as KP-wtGIST by Sanger sequencing and 16 were confirmed by central molecular screening with NGS. Finally, 15 were enrolled and received regorafenib. The study was prematurely closed due to the low accrual worsened by COVID outbreak. The DCR at 12 weeks was 86.7% by central assessment. A subset of 60% experienced some tumor shrinkage, with partial responses and stabilization observed in 13% and 87% respectively, by central assessment. SDH-deficient GIST showed better clinical outcome than other KP-wtGIST. CONCLUSIONS: Regorafenib activity in KP-wtGIST compares favorably with other tyrosine kinase inhibitors, especially in the SDH-deficient GIST subset and it should be taken into consideration as upfront therapy of advanced KP-wtGIST. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02638766.

Perianal Paget's disease.

The incidence of extramammary Paget's disease (EMPD) is very low. It is very important to distinguish between primary Paget's disease and secondary to another process. An 85-year-old man consulted for the presence of an erythematous plaque located in the anal and gluteal area, confirming Paget cells in the biopsy.

Frequency of low-level and high-level mosaicism in sporadic retinoblastoma: genotype-phenotype relationships.

Somatic mutational mosaicism is a common feature of monogenic genetic disorders, particularly in diseases such as retinoblastoma, with high rates of de novo mutations. The detection and quantification of mosaicism is particularly relevant in these diseases, since it has important implications for genetic counseling, patient management, and probably also on disease onset and progression. In order to assess the rate of somatic mosaicism (high- and low-level mosaicism) in sporadic retinoblastoma patients, we analyzed a cohort of 153 patients with sporadic retinoblastoma using ultra deep next-generation sequencing. High-level mosaicism was detected in 14 out of 100 (14%) bilateral patients and in 11 out of 29 (38%) unilateral patients in whom conventional Sanger sequencing identified a pathogenic mutation in blood DNA. In addition, low-level mosaicism was detected in 3 out of 16 (19%) unilateral patients in whom conventional screening was negative in blood DNA. Our results also reveal that mosaicism was associated to delayed retinoblastoma onset particularly in unilateral patients. Finally we compared the level of mosaicism in different tissues to identify the best DNA source to identify mosaicism in retinoblastoma patients. In light of these results we recommended analyzing the mosaic status in all retinoblastoma patients using accurate techniques such as next-generation sequencing, even in those cases in which conventional Sanger sequencing identified a pathogenic mutation in blood DNA. Our results suggest that a significant proportion of those cases are truly mosaics that could have been overlooked. This information should be taking into consideration in the management and genetic counseling of retinoblastoma patients and families.

A study of the suitability of autoencoders for preprocessing data in breast cancer experimentation.

Breast cancer is the most common cause of cancer death in women. Today, post-transcriptional protein products of the genes involved in breast cancer can be identified by immunohistochemistry. However, this method has problems arising from the intra-observer and inter-observer variability in the assessment of pathologic variables, which may result in misleading conclusions. Using an optimal selection of preprocessing techniques may help to reduce observer variability. Deep learning has emerged as a powerful technique for any tasks related to machine learning such as classification and regression. The aim of this work is to use autoencoders (neural networks commonly used to feed deep learning architectures) to improve the quality of the data for developing immunohistochemistry signatures with prognostic value in breast cancer. Our testing on data from 222 patients with invasive non-special type breast carcinoma shows that an automatic binarization of experimental data after autoencoding could outperform other classical preprocessing techniques (such as human-dependent or automatic binarization only) when applied to the prognosis of breast cancer by immunohistochemical signatures.

Expression of dog1 in low-grade fibromyxoid sarcoma: A study of 19 cases and review of the literature.

DOG1 is a highly-sensitive marker often included in the immunohistochemical panel for the diagnosis of gastrointestinal stromal tumors (GISTs). Recent research has shown that DOG1 may also be expressed by low-grade fibromyxoid sarcomas (LGFMSs); this may give rise to diagnostic error when the sarcoma is located in the abdominal cavity. This paper reports on immnohistochemical expression of DOG1 in 19 LGFMSs using two different monoclonal antibodies: K9 (Leica, Novocastra Laboratories, Newcastle upon Tyne, UK) and SP31 (Thermo Scientific, Freemont, USA). All LGFMSs displayed the standard histological pattern of alternating myxoid and fibrous areas, low cellularity and bland spindle-cell morphology. Positive staining for MUC4 was observed in 18/19 cases (94.7%), while there was rearrangement of the FUS gene in 14/19 (73.7%) cases and of the EWR1 gene in 2/19 (10.5%). The sarcoma staining negative for MUC4 displayed FUS gene rearrangement. Whole-section immunohistochemistry revealed positive staining for DOG1 in 8/19 cases (42.1%), though only with clone K9. Cytoplasmic as well as membrane staining was observed in all cases; staining was focal (10-30%) and of varying intensity (1+ to 2+). In conclusion, DOG1 clone K9 exhibited low sensitivity (42.1%) for the diagnosis of LGFMS, although higher than clone SP31. Since the two clones display similar sensitivity and specificity for GIST diagnosis, SP31 would appear to be more specific for this purpose, since no reaction was observed here with LGFMS, a GIST-mimicking lesion.

Epidemiology of Barrett's esophagus and esophageal adenocarcinoma in Spain. A unicentric study.

INTRODUCTION: Barrett's esophagus (BE) is an acquired disease defined by the presence of intestinal metaplasia with goblet cells in the distal esophagus. The prevalence of BE has increased dramatically over the last years. AIMS: The primary aims of the study were to analyze the characteristics of BE and esophageal adenocarcinoma (EAC) in a Spanish health district during a follow-up period. METHODOLOGY: Sociodemographic factors, alcohol consumption and cigarette smoking were analyzed. We also studied the histological behavior and cause of death in each group. RESULTS: In the present study 430 patients were included, 338 with BE and 92 with EAC. Incidence rates have risen from 2.25 and 1.25 per 100,000 inhabitants in 1996 to 6.5 and 4.75 per 100,000 in 2011, respectively. In the EAC group, male gender, age and alcohol consumption were higher in comparison to the BE group, and the overall survival was 23 months. In the BE group, the main causes of death were non-esophageal cancer and cardiovascular disease. CONCLUSIONS: The incidence and prevalence rates of AEC and BE have risen over the past years. Risk factors for these conditions were male gender, age and alcohol consumption. Long BE (> 3 cm) is involved in dysplasia progression. AEC diagnosis mainly occurs after neoplasia is detected and, in a few cases, due to a previous BE. Cardiovascular diseases and non-esophageal cancers have been found to be the main cause of death in BE patients.

Tumor microRNA expression profiling identifies circulating microRNAs for early breast cancer detection.

BACKGROUND: The identification of novel biomarkers for early breast cancer detection would be a great advance. Because of their role in tumorigenesis and stability in body fluids, microRNAs (miRNAs) are emerging as a promising diagnostic tool. Our aim was to identify miRNAs deregulated in breast tumors and evaluate the potential of circulating miRNAs in breast cancer detection. METHODS: We conducted miRNA expression profiling of 1919 human miRNAs in paraffin-embedded tissue from 122 breast tumors and 11 healthy breast tissue samples. Differential expression analysis was performed, and a microarray classifier was generated. The most relevant miRNAs were analyzed in plasma from 26 healthy individuals and 83 patients with breast cancer (36 before and 47 after treatment) and validated in 116 healthy individuals and 114 patients before treatment. RESULTS: We identified a large number of miRNAs deregulated in breast cancer and generated a 25-miRNA microarray classifier that discriminated breast tumors with high diagnostic sensitivity and specificity. Ten miRNAs were selected for further investigation, of which 4 (miR-505-5p, miR-125b-5p, miR-21-5p, and miR-96-5p) were significantly overexpressed in pretreated patients with breast cancer compared with healthy individuals in 2 different series of plasma. MiR-505-5p and miR-96-5p were the most valuable biomarkers (area under the curve 0.72). Moreover, the expression levels of miR-3656, miR-505-5p, and miR-21-5p were decreased in a group of treated patients. CONCLUSIONS: Circulating miRNAs reflect the presence of breast tumors. The identification of deregulated miRNAs in plasma of patients with breast cancer supports the use of circulating miRNAs as a method for early breast cancer detection.

Gastrointestinal stromal tumors (GISTs): role of CD 117 and PDGFRA Golgi-like staining pattern in the recognition of mutational status.

AIMS: to determine whether potential correlations between CD117 and PDGFRA might serve as an indication for targeted therapies. MATERIAL AND METHODS: immunohistochemical expression of CD117 and PDGFRA was evaluated in 99 paraffin-embedded GISTs in conjunction with KIT and PDGFRA mutational status. RESULTS: CD117-positive staining was noted in 93 out of 99 cases. The predominant staining pattern was cytoplasmic, either with or without membrane accentuation; in 44.5% of cases, a clear Golgi-like pattern was evident. Correlations were found between KIT mutation and both CD117 expression (p = 0.006) and Golgi-like pattern (p = 0.026). Cytoplasmic PDGFRA-positive staining was detected in 87% of cases, both with and without membrane accentuation; in 8% cases an evident Golgi-like staining pattern was observed. A significant correlation was noted between PDGFRA mutations and Golgi-like staining pattern (p = 0.001). Moreover, 95% of PDGFRA-positive GISTs were also CD117-positive, suggesting that expression of the two markers is not mutually exclusive; most of these had mutations in KIT exon 11. PDGFRA-positive/CD117-negative tumors had mutations in PDGFRA, mainly in exon 18. PDGFRA-negative/CD117-negative staining was observed in 15% of cases, all of which displayed mutations in KIT exon 11. CD117-positive/PDGFRA-negative cases were characterized by mutations in KIT, mainly in exon 11. CONCLUSIONS: CD117 and PDGFRA staining are not exclusive, and the presence of a Golgi-like staining pattern for either, whilst not pathognomonic, is highly suggestive of KIT and PDGFRA mutated GISTs, respectively, and may be used with some reservations as an alternative indication for prescribing targeted therapies.

Epithelioid Sarcoma in the Median Nerve of the Hand: A Case Report.

Epithelioid sarcoma of the peripheral nerves is extremely rare. We present a case concerning the median nerve of the right hand in a 35-year-old woman who was treated with radical resection, reconstructive surgery, and chemotherapy. After 2 years of follow-up, there is no evidence of local recurrence or metastatic dissemination.

Human papillomavirus detection by PCR assay in a large series of high-grade squamous intraepithelial lesions with cytohistological correlation and follow-up.

OBJECTIVE: High-grade squamous intraepithelial lesions (HSIL) are the precursors of invasive cervical carcinomas and are generally associated with the integration of mucosotropic human papillomavirus (HPV) DNA into the host cell genome. Detection of HPV is easy to perform nowadays, even in laboratories with limited technological capacity, and follow-up procedures for patients with HSIL are well established. STUDY DESIGN: HPV detection was performed in a large group of patients with HSIL, and results were correlated with cytological, histological, and colposcopic findings. Discrepancies were examined and discussed. RESULTS: Conventional Papanicolaou (Pap) screening detected 446 HSIL (0.20%) in 218,906 cervical smears. HPV detection by PCR was positive in 339/358 (94.7%) patients. The strains involved were: HPV 16 in 180 patients (53.1%), HPV 18 in 35 (10.3%), HPV 31/33 in 27 (8%), HPV 6/11 in 10 (2.96%), and an unidentified type in 73 (30%). For the last 97 patients (2006-2007), HPV typing was expanded with the following results: HPV 52 was detected in 9 patients (9.2%), HPV 58 in 6 (6.1%), HPV 51 in 4 (4.1%), HPV 68 in 2 (2.0%), and HPV 39 in 1 (1.0%). The number of nonidentified patients dropped to 9 (9.4%); in addition, 14/97 (14.4%) patients were infected with 2 or more viral types. Finally, 19 (5.3%) patients were HPV negative. Colposcopy revealed minor changes in 59 patients (17.3%), major changes in 264 (77.6%), and normal findings in 17 (5.1%). A biopsy was taken in 331/446 patients, and the diagnosis of HSIL or overt malignancy was histologically confirmed in 281 (84.9%) patients: CIN II in 46, CIN III in 224, and histologically upgraded in 11 (6 microinvasive squamous carcinomas, 1 squamous carcinoma, 2 in situ endocervical adenocarcinomas, and 2 microinvasive endocervical adenocarcinomas). Thirty-five patients (10.6%) were downgraded to CIN I and 15 (4.5%) patients had a negative biopsy. Follow-up in the negative-biopsy patients confirmed the existence of SIL in 11 patients [1 HSIL and 10 low-grade squamous intraepithelial lesions (LSIL)] while 4 were considered false positives (atrophic changes, 2; reactive changes, 2). After treatment, 31/331 (9.36%) patients displayed recurrence (HSIL in 29 and LSIL in 2). The viral strains involved in patients with recurrence were HPV 16 in 16 patients (51.6%); HPV 18 in 4 (12.9%); HPV 16 and 18 in 1 (3.2%); HPV 31 in 1 (3.2%); HPV 52 in 1 (3.2%); HPV 18, 31, and 58 in 1 (3.2%); HPV 68 in 1 (3.2%); HPV 51 and 73 in 1 (3.2%), and an unidentified type in 5 (16.1%). Follow-up in 14/19 HSIL and HPV-negative patients confirmed the existence of cervical pathology. CONCLUSIONS: HPV detection improves diagnostic sensitivity and provides an ideal tool for monitoring the response to treatment in HSIL patients. The pathogenic relevance of HPV strain 18 may be greater than previously assumed.

Leiomyo-adenomatoid tumor of the uterus: a distinct morphological entity?

INTRODUCTION: The morphologic and immunohistochemical findings of a well-circumscribed leiomyoadenomatoid tumor located in the posterior uterine wall are reported. CASE REPORT: The patient was a 55-year-old white woman who complained of peri/postmenopausal and irregular bleeding during the past 4 months. The adenomatoid component was intermingled with bland smooth muscle fascicles and was composed of vacuolated cells, tubules, and slit-like structures crossed by epithelial bridges. Immunohistochemistry revealed positivity to epithelial and mesothelial markers in the adenomatoid component and strong immunoreaction for smooth muscle markers in the leiomyomatous one. CONCLUSIONS: The well-defined circumscription and the presence of mesothelial component intermingled with the leiomyomatous proliferation favors the hypothesis that a leiomyo-adenomatoid tumor should be considered as a subtype of adenomatoid tumor with distinctive morphological features. Only four previous cases of this rare neoplasm have been reported to date, one in the epydidimis and the other three cases in the uterine wall, one of them affecting also to the right ovary.

BCL-2, TP53 and BAX protein expression in superficial urothelial bladder carcinoma.

Whether TP53, BCL-2 and BAX expressions add independent prognostic information in patients with Ta/T1 bladder urothelial carcinoma remains unclear. TP53 overexpression correlated with high tumor grade (p=0.004), WHO grading categories (0.045), BAX expression (p=0.043) and pathologic stage (p=0.05). BCL-2 immunostaining was inverse associated with tumor grade (p=0.008). Lack of BAX expression was related to reduced patient's survival (p=0.028). Mortality was higher in patients with BCL-2+/TP53+ (p=0.023) or TP53+/BAX- (p=0.027) phenotype. BAX and pathologic stage were independent predictors of progression-free and overall survival, respectively. Therefore, BAX expression might be relevant in patient's prognosis.

Expression of P-glycoprotein and metallothionein in gastrointestinal stromal tumor and leiomyosarcomas. Clinical implications.

We investigated the expression of P-glycoprotein (P-GP) and metallothionein (MT) in a series of 92 GIST and 14 gastrointestinal leiomyosarcomas (GILMS) with the purpose to expand our knowledge on the biological bases of GIST chemo-resistance and to ascertain their significance in patients' prognosis. P-GP expression was more frequent in GIST than in GI-LMS (83.7% vs. 21.4%, p<0.001), with no difference between low- and high-risk GIST (p=1.000) or low- and high-grade GI-LMS (p=0.538). P-GP expression was unrelated to anatomic location (gastric vs. intestinal) in GIST (39/45 vs. 35/43, p=0.770) and in GI-LMS (0/2 vs. 2/6, p=1.000). MT expression was non-significantly higher in GI-LMS than in GIST (35.7% vs. 14.1%, p=0.060), with no difference between low- and high-risk GIST (p=1.000) or low- and high-grade GI-LMS (p=1.000). MT expression was unrelated to the anatomic location (gastric vs. intestinal) in GIST (7/45 vs. 6/43) and GI-LMS (0/2 vs. 1/6) (p=1.000 and p=0.1000, respectively). Overall tumor-specific survival (p< 0.001) and disease-free survival (p<0.001) were different in GIST as compared with GI-LMS, and the number of events was higher in GI-LMS. When the survival analysis took into consideration P-GP or MT expression, the overall survival in GIST was influenced by the expression of MT (p=0.021) but not by that of P-GP (p=0.638). However, in GI-LMS, P-GP expression influenced disease-free survival (p=0.050); in addition, it is important to recognize the limited value of these results because of the low number of cases involved in the study. Differential expression of P-GP and MT might explain the known variability in response to systemic chemotherapy in these tumors. Detection of P-GP and MT seems to add certain prognostic value in GIST (MT) or GI-LMS (P-GP).

Apoptotic and proliferation indexes in primary superficial bladder tumors.

Whether apoptotic index [AI] and/or Ki-67 labeling index [Ki-67LI] add prognostic information in bladder cancer remains unclear. Mean AI and Ki-67 LI increased with grade and stage in 147 superficial bladder tumors. AI (>1.7%) correlated with tumor size, grade and proliferation. Ki-67 LI (>10%) correlated with higher grade and stage. Tumor size and Ki-67 LI were independent predictors of disease-free and progression-free survival, respectively. Tumor size, patient's age and tumor's recurrence predicted overall survival. We conclude that conventional clinical parameters and Ki-67 LI define risk groups of bladder tumors, while AI has limited value.

Chromosome-12 copy number alterations and MDM2, CDK4 and TP53 expression in soft tissue liposarcoma.

BACKGROUND: Liposarcoma is a heterogeneous group of soft tissue sarcomas in which definitive prognostic parameters need to be identified. MATERIALS AND METHODS: The series included 33 consecutive soft tissue (well-differentiated, WDLPS, n=19; and dedifferentiated, DDLPS, n=14) liposarcoma. Clinicopathological variables included age, gender, body location, degree of dedifferentiation and mitotic count. The rrolecular analysis included MDM2, CDK4 and TP53 expressions and chromosome-12 copy number alterations. RESULTS: Centrally located (retroperitoneal, abdominal cavity or groin region) WDLPS had more dedifferentiation (p=0.001). Patients with DDLPS and a high mitotic rate died (p=0.070) or experienced recurrencies (p=0.029) more frequently. Co-expression of MDM2/CDK4 (p=0.001) and TP53 accumulation (p=0.017) related to dedifferentiation but not to recurrence or death, both in WDLPS and DDLPS. DDLPS had higher centromeric chromosome-12 copy number than WDLPS (p=0.013), but this was unrelated to recurrence or death. CONCLUSION: Central location is a risk factor in WDLP. Co-expression of MDM2/CDK4/TP53 and chromosome-12 alterations characterize DDLPS suggesting a link with dedifferentiation.