A nationwide pilot study on breast cancer screening in Peru.

Introduction: A high prevalence of advanced breast cancer (BC) is a common scenario in Latin America. In Peru, the frequency of BC at Stages III/IV is ≈50% despite implementation of a programme for breast cancer screening (BCS) along the country. We carried out a study to assess the feasibility and develop an instrument to evaluate the knowledge, barriers and perception about BCS in a nationwide pilot study in Peru among candidates for BCS. Methods: We conducted a systematic review of 2,558 reports indexed in PubMed, Scopus, Web of Science, Medline-Ovid and EMBASE, regarding to our study theme. In total, 111 were selected and a 51-items survey was developed (eight items about sociodemographic characteristics). Patients were recruited in public hospitals or private clinics, in rural and urban areas of nine departments of Peru. Results: We surveyed 488 women from: Lima (150), Cajamarca (93), Ica (59), Arequipa (56), Loreto (48), Ancash (38), Junín (15), Puerto Maldonado (15) and Huancavelica (14); 27.9% of them were from rural areas. The mean of age was 53.3 years (standard deviation ± 9.1). Regarding education level, 29.8% had primary, 33.2% secondary and 37.0% higher education. In total, 28.7% of women did not know the term 'mammogram' and 47.1% reported never receiving a BCS (36.9% from urban and 73.5% from rural population). In women that underwent BCS, only 67% knew it is for healthy women. In total, 54.1% of patients had low levels of knowledge about risk factors for BC (i.e. 87.5% of women respond that injuries in the breast produce cancer). Cultural, economic and geographic barriers were significantly associated with having a mammogram where 56.9% of participants considered a cost ≤ 7 USD as appropriate. Mammogram was perceived as too painful for 54.9% of women. In addition, women with a self-perception of low-risk for BC and a fatalistic perception of cancer were less likely to have a BCS. Conclusion: We found that it is feasible to conduct a large-scale study in Peru. The results of this pilot study highlight an urgent need of extensive education and awareness about BCS in Peru.

Repeated observation of immune gene sets enrichment in women with non-small cell lung cancer.

There are different biological and clinical patterns of lung cancer between genders indicating intrinsic differences leading to increased sensitivity to cigarette smoke-induced DNA damage, mutational patterns of KRAS and better clinical outcomes in women while differences between genders at gene-expression levels was not previously reported. Here we show an enrichment of immune genes in NSCLC in women compared to men. We found in a GSEA analysis (by biological processes annotated from Gene Ontology) of six public datasets a repeated observation of immune gene sets enrichment in women. "Immune system process", "immune response", "defense response", "cellular defense response" and "regulation of immune system process" were the gene sets most over-represented while APOBEC3G, APOBEC3F, LAT, CD1D and CCL5 represented the top-five core genes. Characterization of immune cell composition with the platform CIBERSORT showed no differences between genders; however, there were differences when tumor tissues were compared to normal tissues. Our results suggest different immune responses in NSCLC between genders that could be related with the different clinical outcome.

A prognostic signature based on three-genes expression in triple-negative breast tumours with residual disease.

Residual disease after neoadjuvant chemotherapy (NAC) in triple-negative breast cancer (TNBC) is related with poor prognosis; however, the risk of recurrence after 3 years from surgery, becomes similar to other breast cancer subtypes indicating that TNBC is composed of tumours of different prognosis. To evaluate genes related to TNBC aggressiveness in the outcome of TNBC resistant to NAC, we profiled 82 samples of residual tumours whose expression for 449 genes was quantified with NanoString. The validation set (GSE25066) consisted of 113 TNBC cases with residual disease. The stepwise multivariate survival analysis performed by the Cox proportional hazards mode selected CCL5, DDIT4 and POLR1C as independent prognostic factors for distant recurrence-free survival (DRFS). We developed a three-genes signature using the regression coefficients for each gene (-0.393×CCL5+0.443×DDIT4+0.490×POLR1C). The median score in the discovery set (0.1494) identified two subgroups with different DRFS (P<0.001). The median score in the validation set was 0.0024 and was able to discriminate patients with different DRFS (P=0.002). In addition, the three-genes signature was a prognostic factor in TNBC patients regardless their response to NAC (data set GSE58812; P=0.001) and in patients with oestrogen-receptor-negative tumours (data set GSE16446; P=0.041). Here we describe a prognostic signature based on expression levels of CCL5, DDIT4 and POLR1C. The knowledge about the involvement of these genes in chemotherapy resistance could improve the therapeutic strategies in TNBC.