Gallbladder Cancer Risk and Indigenous South American Mapuche Ancestry: Instrumental Variable Analysis Using Ancestry-Informative Markers.

A strong association between the proportion of indigenous South American Mapuche ancestry and the risk of gallbladder cancer (GBC) has been reported in observational studies. Chileans show the highest incidence of GBC worldwide, and the Mapuche are the largest indigenous people in Chile. We set out to assess the confounding-free effect of the individual proportion of Mapuche ancestry on GBC risk and to investigate the mediating effects of gallstone disease and body mass index (BMI) on this association. Genetic markers of Mapuche ancestry were selected based on the informativeness for assignment measure, and then used as instrumental variables in two-sample Mendelian randomization analyses and complementary sensitivity analyses. Results suggested a putatively causal effect of Mapuche ancestry on GBC risk (inverse variance-weighted (IVW) risk increase of 0.8% per 1% increase in Mapuche ancestry proportion, 95% CI 0.4% to 1.2%, p = 6.7 × 10-5) and also on gallstone disease (3.6% IVW risk increase, 95% CI 3.1% to 4.0%), pointing to a mediating effect of gallstones on the association between Mapuche ancestry and GBC. In contrast, the proportion of Mapuche ancestry showed a negative effect on BMI (IVW estimate -0.006 kg/m2, 95% CI -0.009 to -0.003). The results presented here may have significant implications for GBC prevention and are important for future admixture mapping studies. Given that the association between the individual proportion of Mapuche ancestry and GBC risk previously noted in observational studies appears to be free of confounding, primary and secondary prevention strategies that consider genetic ancestry could be particularly efficient.

Development and internal validation of a multifactorial risk prediction model for gallbladder cancer in a high-incidence country.

Since 2006, Chile has been implementing a gallbladder cancer (GBC) prevention program based on prophylactic cholecystectomy for gallstone patients aged 35 to 49 years. The effectiveness of this prevention program has not yet been comprehensively evaluated. We conducted a retrospective study of 473 Chilean GBC patients and 2137 population-based controls to develop and internally validate three GBC risk prediction models. The Baseline Model accounted for gallstones while adjusting for sex and birth year. Enhanced Model I also included the non-genetic risk factors: body mass index, educational level, Mapuche surnames, number of children and family history of GBC. Enhanced Model II further included Mapuche ancestry and the genotype for rs17209837. Multiple Cox regression was applied to assess the predictive performance, quantified by the area under the precision-recall curve (AUC-PRC) and the number of cholecystectomies needed (NCN) to prevent one case of GBC at age 70 years. The AUC-PRC for the Baseline Model (0.44%, 95%CI 0.42-0.46) increased by 0.22 (95%CI 0.15-0.29) when non-genetic factors were included, and by 0.25 (95%CI 0.20-0.30) when incorporating non-genetic and genetic factors. The overall NCN for Chileans with gallstones (115, 95%CI 104-131) decreased to 92 (95%CI 60-128) for Chileans with a higher risk than the median according to Enhanced Model I, and to 80 (95%CI 59-110) according to Enhanced Model II. In conclusion, age, sex and gallstones are strong risk factors for GBC, but consideration of other non-genetic factors and individual genotype data improves risk prediction and may optimize allocation of financial resources and surgical capacity.

Identification of Circulating lncRNAs Associated with Gallbladder Cancer Risk by Tissue-Based Preselection, Cis-eQTL Validation, and Analysis of Association with Genotype-Based Expression.

Long noncoding RNAs (lncRNAs) play key roles in cell processes and are good candidates for cancer risk prediction. Few studies have investigated the association between individual genotypes and lncRNA expression. Here we integrate three separate datasets with information on lncRNA expression only, both lncRNA expression and genotype, and genotype information only to identify circulating lncRNAs associated with the risk of gallbladder cancer (GBC) using robust linear and logistic regression techniques. In the first dataset, we preselect lncRNAs based on expression changes along the sequence "gallstones → dysplasia → GBC". In the second dataset, we validate associations between genetic variants and serum expression levels of the preselected lncRNAs (cis-lncRNA-eQTLs) and build lncRNA expression prediction models. In the third dataset, we predict serum lncRNA expression based on individual genotypes and assess the association between genotype-based expression and GBC risk. AC084082.3 and LINC00662 showed increasing expression levels (p-value = 0.009), while C22orf34 expression decreased in the sequence from gallstones to GBC (p-value = 0.04). We identified and validated two cis-LINC00662-eQTLs (r2 = 0.26) and three cis-C22orf34-eQTLs (r2 = 0.24). Only LINC00662 showed a genotyped-based serum expression associated with GBC risk (OR = 1.25 per log2 expression unit, 95% CI 1.04-1.52, p-value = 0.02). Our results suggest that preselection of lncRNAs based on tissue samples and exploitation of cis-lncRNA-eQTLs may facilitate the identification of circulating noncoding RNAs linked to cancer risk.

Gallstones, Body Mass Index, C-Reactive Protein, and Gallbladder Cancer: Mendelian Randomization Analysis of Chilean and European Genotype Data.

BACKGROUND AND AIMS: Gallbladder cancer (GBC) is a neglected disease with substantial geographical variability: Chile shows the highest incidence worldwide, while GBC is relatively rare in Europe. Here, we investigate the causal effects of risk factors considered in current GBC prevention programs as well as C-reactive protein (CRP) level as a marker of chronic inflammation. APPROACH AND RESULTS: We applied two-sample Mendelian randomization (MR) using publicly available data and our own data from a retrospective Chilean and a prospective European study. Causality was assessed by inverse variance weighted (IVW), MR-Egger regression, and weighted median estimates complemented with sensitivity analyses on potential heterogeneity and pleiotropy, two-step MR, and mediation analysis. We found evidence for a causal effect of gallstone disease on GBC risk in Chileans (P = 9 × 10-5 ) and Europeans (P = 9 × 10-5 ). A genetically elevated body mass index (BMI) increased GBC risk in Chileans (P = 0.03), while higher CRP concentrations increased GBC risk in Europeans (P = 4.1 × 10-6 ). European results suggest causal effects of BMI on gallstone disease (P = 0.008); public Chilean data were not, however, available to enable assessment of the mediation effects among causal GBC risk factors. CONCLUSIONS: Two risk factors considered in the current Chilean program for GBC prevention are causally linked to GBC risk: gallstones and BMI. For Europeans, BMI showed a causal effect on gallstone risk, which was itself causally linked to GBC risk.

ABCB1/4 gallbladder cancer risk variants identified in India also show strong effects in Chileans.

BACKGROUND: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. METHODS: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. RESULTS: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. CONCLUSION: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs.

Diagnóstico diferencial de tuberculosis en base a PCR en lesiones granulomatosas clasificadas histopatológicamente / PCR-based differential diagnosis of tuberculosis in histopathologically classified granulomatous lesions

El diagnóstico diferencial de tuberculosis en tejidos fijados en formalina e incluidos en parafina es necesario porque la morfología de la lesión tuberculosa es variada, hay diversos granulomas clasificados en necrobióticos, tuberculoideos, supurativos, sarcoideo, a cuerpo extraño/crónico inespecífico. Las lesiones granulomatosas ocurren en tuberculosis y también en otras infecciones (hongos, parásitos, brucelosis, lepra) en condiciones tóxicas, alérgicas, autoinmunes, tumores y otras. El diagnóstico histológico no es confirmatorio de tuberculosis y en ausencia de una baciloscopia positiva, se hace necesaria la confirmación molecular para el diagnóstico diferencial. Evaluamos la eficacia de la técnica de PCR para la detección de tuberculosis en tejidos fijados y comparamos esos resultados con la histología del granuloma y la baciloscopia. Analizamos 444 biopsias de diferentes tejidos (ganglios, piel, pleura, pulmón, intestino, tejido óseo, mama y otros) de 5 tipos de granulomas: G1.tuberculoideo con necrosis caseosa; G2.tuberculoideo sin necrosis caseosa; G3. supurativo; G4. sarcoideo l; G5. a cuerpo extraño/inespecífico. Utilizamos dos PCR-IS6110 nested para detección del complejo Mycobacterium tuberculosis y un pan PCR-hsp65 nested para detección de Mycobacterium spp. Los resultados obtenidos muestran que la detección de tuberculosis mediante PCR fue significativamente superior que mediante baciloscopia. G1: PCR 69,6%, baciloscopia 31,3%; G2: PCR 26,8%, baciloscopia 6,1%; G3: PCR 16,7%, baciloscopia 6,7%; G4: PCR 7%, baciloscopia 4%; G5: PCR 6,7%, baciloscopia 0%. Concluimos que el diagnóstico molecular de tuberculosis mediante un PCR robusto adaptado a tejidos fijados es eficaz, rápido, sensible y contribuye a la precisión del diagnóstico diferencial en diferentes tipos de granulomas (AU)

The differential diagnosis of tuberculosis in fixed paraffin embedded-tissues is necessary due to both the diverse morphology of tuberculous lesions and the varying histological types of granulomas (necrobiotic, tuberculoid, suppurative, sarcoidal and foreign body/inespecific). Granulomatous lesions occur in tuberculosis, in other infections (fungal, parasitic, brucelosis, lepra), in toxic, allergic and autoimmune, tumours and in conditions of unknown etiology. Diagnosis of tuberculosis cannot be confirmed by histopathology alone and in absence of a positive acid-fast bacilli (AFB) stain, molecular confirmation of tuberculosis is necessary for a correct differential diagnosis. The aim of our study was to assess PCR efficacy for mycobacterial infection detection in fixed tissues and to correlate those findings with granuloma histology and with AFB staining. We analyzed 444 biopsies from various tissues (lymph nodes, skin, pleura, lung, intestine, bone tissue, breast and others) with 5 granuloma types: G1: with caseous necrosis; G2: without caseous necrosis; G3: suppurative; G4: sarcoidal; G5: chronic/nonspecific. For molecular detection, we used nested PCR-IS6110 for Mycobacterium tuberculosis complex and a nested pan PCR-hsp65 for Mycobacterium sp.. The results obtained demonstrated that PCR was significantly better than AFB stain for tuberculosis detection. G1: PCR 69.6%, AFB staining 31.3%. G2: PCR 26.8%, AFB staining 6.1%; G3: PCR 16.7%, AFB staining 6.7%; G4: PCR 7%, AFB staining 4%. G5: PCR 6.7%, AFB staining 0%. We conclude that molecular diagnosis of tuberculosis using robust PCR-based testing adapted to fixed tissues is a fast, efficient and sensitive method that increases the accuracy of the differential diagnosis of granulomatous lesions (AU)

Eficacia del diagnóstico diferencial de tuberculosis mediante reacción de polimerasa en cadena en lesiones granulomatosas de tejidos fijados en formalina e incluidos en parafina / Efficacy of PCR for the differential diagnosis of tuberculosis in granulomatous lesions of paraffin-embedded formalin fixed tissues

Background: Granulomatous lesions occur in tuberculosis (TB), other infections, toxic, allergic, and autoimmune diseases among others. In absence of a an acid-fast bacilli (AFB) confirmation of TB is necessary. Objective: To assess the efficacy of PCR for TB detection and to correlate with granuloma histology and AFB staining. Methods: We analyzed 380 fixed paraffin-embedded tissues (PETs) of granulomas with and without caseous necrosis; suppurative; sarcoidal; or of chronic nonspecific nature. Nested PCR-IS6110 for Mycobacterium tuberculosis complex (MTB) and a nested pan-Mycobacterium for the hsp65 gene were used for Mycobacterium spp detection. Results: PCR was more sensitive than AFB staining for all five catageories of granulomas: G1: PCR 71%, AFB staining 28%. G2: PCR 37%, AFB 8%. G3: PCR 17%, AFB staining 7%. G4: PCR 8%, AFB staining 4%. G5: PCR 6%, AFB staining 0%. Conclusions: Molecular diagnosis of TB using PCR-based testing is a fast, efficacious and sensitive method that increased the accuracy of PET histological diagnosis associated with granulomatous lesions.

Introducción: Lesiones granulomatosas ocurren en tuberculosis (TBC), otras infecciones, condiciones tóxicas, alérgicas y autoinmunes, entre otras. Con baciloscopia negativa, es necesario confirmar el diagnóstico de TBC. Objetivo: Evaluar la eficacia de la RPC para detectar TBC comparado con baciloscopia en relación a la histología del granuloma. Métodos: Analisis de 380 tejidos fijados en formalina e incluidos en parafina (TFFP) con diferentes tipos de granulomas: con necrosis caseosa; sin necrosis caseosa; supurativo; sarcoidal; a cuerpo extraño/inespecífico. Utilizamos RPC anidada-IS6110 para detección del complejo Mycobacterium tuberculosis (MTB) y una pan-RPC anidada-hsp65 para Mycobacterium spp. Resultados: La detección de TBC mediante RPC fue significativamente superior a baciloscopia en los cinco tipos de granuloma: G1: RPC 71%, baciloscopia 28%; G2: RPC 37%, baciloscopia 8%; G3: RPC 17%, baciloscopia 7%; G4: RPC 8%, baciloscopia 4%; G5: RPC 6%, baciloscopia 0%. Conclusión: El diagnóstico de TBC por RPC es un método rápido, eficaz y de gran sensibilidad, que aumenta la precisión del diagnóstico diferencial de lesiones granulomatosas de TFFP procesados rutinariamente en histopatología.

[Efficacy of PCR for the differential diagnosis of tuberculosis in granulomatous lesions of paraffin-embedded formalin fixed tissues]. / Eficacia del diagnóstico diferencial de tuberculosis mediante reacción de polimerasa en cadena en lesiones granulomatosas de tejidos fijados en formalina e incluidos en parafina.

BACKGROUND: Granulomatous lesions occur in tuberculosis (TB), other infections, toxic, allergic, and autoimmune diseases among others. In absence of a an acid-fast bacilli (AFB) confirmation of TB is necessary. OBJECTIVE: To assess the efficacy of PCR for TB detection and to correlate with granuloma histology and AFB staining. METHODS: We analyzed 380 fixed paraffin-embedded tissues (PETs) of granulomas with and without caseous necrosis; suppurative; sarcoidal; or of chronic nonspecific nature. Nested PCR-IS6110 for Mycobacterium tuberculosis complex (MTB) and a nested pan-Mycobacterium for the hsp65 gene were used for Mycobacterium spp detection. RESULTS: PCR was more sensitive than AFB staining for all five catagories of granulomas: G1: PCR 71%, AFB staining 28%. G2: PCR 37%, AFB 8%. G3: PCR 17%, AFB staining 7%. G4: PCR 8%, AFB staining 4%. G5: PCR 6%, AFB staining 0%. CONCLUSIONS: Molecular diagnosis of TB using PCR-based testing is a fast, efficacious and sensitive method that increased the accuracy of PET histological diagnosis associated with granulomatous lesions.

Multifocal extramedullary plasmocytoma of the sinonasal region: a case report and literature review / Plasmocitoma multifocal extramedular de la región sinonasal: reporte de un caso y revisión de la literatura

We report on a patient who presented to ENT services with right side epistaxis, frontal lobe headache, right infraorbital pain and the feeling of having a stuffy nose. CT and MRI were performed and later a biopsy confirmed the presence of sinonasal plasmocytoma. The Head and Neck oncology committee recommended radiotherapy as the choice of treatment. At the present time the patient is being followed on scheduled medical visits.

Se reporta el caso de un paciente que se presentó en el servicio de Otorrinolaringología con epistaxis, cefalea del lóbulo frontal derecho, dolor infraorbitario derecho y la sensación de tener la nariz tapada. Se realizaron TC y RNM, y luego una biopsia confirmó la presencia de un plasmocitoma nasosinusal. El comité de oncología de cabeza y cuello recomendó radioterapia como tratamiento de elección. En la actualidad, el paciente está en siguimiento y control en las visitas médicas regulares.

Maxillary cuniculatum carcinoma: a case report and literature review / Carcinoma cuniculatum maxilar: presentación de un caso y revisión de la literatura

We report on a patient who presented to our clinic with a volume increase and pain at left maxillary region. A biopsy of the area was performed and the lesion was diagnosed as differentiated squamous cell carcinoma of the type cuniculatum. Due to the size of the tumor and compromise of vital intracraneal structures it was decided to perform surgical drainage and later is evaluated because of the tumor persistence to ultimately use palliative care...

Se presenta a una paciente que acudió a nuestra clínica con un aumento de volumen y dolor en región maxilar izquierda. Se realizó una biopsia del área y la lesión fue diagnosticada como carcinoma de células escamosas diferenciado de tipo cuniculatum. Debido al tamaño del tumor y el compromiso de estructuras intracraneales vitales, se decidió realizar un drenaje quirúrgico y posteriormente se evalúa la causa de la persistencia del tumor para finalmente entregar cuidados paliativos...

Sinonasal mucoepidermoid carcinoma: a case report and literature review / Carcinoma mucoepidermoide nasosinusal: reporte de caso y revisión de la literatura

We report on a patient who presented at our clinic with a growth of the right palate of twenty years duration. A biopsy of the area was performed and the lesion was diagnosed as low-grade mucoepidermoid carcinoma (MEC). Due to the size of the tumor, it was decided to begin treatment with radiotherapy followed by chemotherapy. Once the initial treatment was completed, the lesion was reevaluated and surgery followed by reconstruction was recommended. The Patient rejected the recommended treatment and opted to enrolled in a pain management, palliative care program.

Reportamos sobre un paciente que se presentó con un crecimiento del paladar derecho de veinte años de evolución. Se realizó una biopsia del área y se diagnosticó la lesión como carcinoma mucoepidermoide (MEC) bajo grado. Debido al tamaño del tumor, se decidió comenzar el tratamiento con radioterapia seguida de quimioterapia. Una vez que el tratamiento inicial se completó, la lesión fue reevaluada y se recomendó la cirugía seguida de reconstrucción. El paciente rechazó el tratamiento recomendado y optó por seguir un tratamiento de manejo del dolor, programa de cuidados paliativos.

Immunohistochemical overexpression of platelet-derived growth factor receptor-beta (PDGFR-ß) is associated with PDGFRB gene copy number gain in sarcomatoid non-small-cell lung cancer.

UNLABELLED: Sarcomatoid non-small cell lung cancer (NSCLC) is an uncommon histologic variant that has not been molecularly well-characterized. We conducted immunohistochemical and fluorescence in situ hybridization studies of PDGF-B/PDGFR-b on archived surgically resected specimens and showed high PDGFR-b IHC expression and gene copy number gain. Further studies are warranted to determine whether PDGFR-b is a feasible therapeutic target in this population. INTRODUCTION: Sarcomatoid non-small cell lung cancer (NSCLC) is an uncommon histologic variant that has not been molecularly well-characterized. We hypothesized that the PDGF-B/PDGF-Rß pathway may be dysregulated in sarcomatoid lung cancer. METHODS: We conducted immunohistochemical (IHC) and gene copy number gain studies of PDGF-B/PDGFR-ß on archived surgically resected specimens, 43 sarcomatoid NSCLCs and 42 control NSCLCs that were age, gender and stage-matched. Biomarkers were correlated to patient demographics, tumor characteristics, and survival. RESULTS: Sarcomatoid tumors had higher PDGFR-ß IHC expression than control NSCLC (median score 2.69 vs. 1.93; P < 0.0001). No difference was seen between the two groups of PDGF-B IHC expression; and neither PDGF-B nor PDGFR-ß IHC levels correlated with gender, age, clinical or pathologic TNM status, or overall survival. PDGFRB gene copy number was evaluated by FISH using three ways: presence of amplification, gene copy number gain, and gene copy ratio between tumor and normal tissue. PDGFRB gene copy number gain was associated with sarcomatoid histology (P = 0.006), lower clinical and pathologic T-stage (P = 0.07, P = 0.048), and higher pathologic N-stage (P = 0.013). Sarcomatoid NSCLC patients (P = 0.006) and female patients (P = 0.03) had higher gene copy ratios above 1.83. Higher PDGFR-ß IHC expression in tumor cells was associated with gene copy number gain (P = 0.021) and higher gene copy ratio status (P = 0.005). CONCLUSION: This is the first study to demonstrate high PDGFR-ß IHC expression and gene copy number gain in sarcomatoid NSCLC tumors and suggests that further studies are warranted to determine whether PDGFR-ß is a feasible therapeutic target in this population.

Polypoid leiomyosarcoma of the gallbladder: study of a case associated with adenomyomatous hyperplasia.

A case of polypoid leiomyosarcoma of the gallbladder arising in association with pre-existing adenomyomatous hyperplasia is described. The patient, a 34-year-old woman with symptoms of cholelithiasis, underwent a cholecystectomy for gallstones. The resected specimen showed, in addition to multiple stones, a large, rubbery, broad-based polypoid mass in the fundus. Histologic examination showed a malignant spindle cell proliferation with immunophenotypic features of smooth muscle differentiation. The base of the lesion showed features of adenomyomatous hyperplasia. The possible relationships of this lesion with adenomyomatous hyperplasia and other stromal lesions of the gallbladder are reviewed.