Browsing by Author "Camus, Mauricio"
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- ItemATM allelic variants associated to hereditary breast cancer in 94 Chilean women: susceptibility or ethnic influences?(2008) Tapia, Teresa; Sanchez, Alejandro; Vallejos, Maricarmen; Alvarez, Carolina; Moraga, Mauricio; Smalley, Susan; Camus, Mauricio; Alvarez, Manuel; Carvallo, PilarBesides BRCA1 and BRCA2, two genes accounting for a small proportion of breast cancer cases, ATM has been widely proposed as a low-penetrance susceptibility gene. Several nucleotide changes have been proposed to be associated with breast cancer, still remaining a high controversy in this sense. We screened the ATM gene in 94 breast cancer patients selected from 78 high-risk families, not presenting a mutation in BRCA1 or BRCA2. We found three novel allelic variants: IVS64 + 51delT and p.L752L, not showing association with hereditary breast cancer, and p.L694L found in one family in two breast cancer patients. Two amino acid substitutions p.S707P and p.F858L, previously reported to be associated with breast cancer, were present in our study in cases and controls, lacking of association with breast cancer. A positive association of c. 5557G > A (p.D1853N) was found (OR 2.52, P = 0.008), when analyzed alone and in combination with an intronic variant IVS24-9delT (OR 3.97; P = 0.0003). We postulate that our discrepancies with other reports related to the associated ATM alleles to hereditary breast cancer, as well as discrepancies in the literature between other groups, could be explained by the diversity in the ethnic origins of families gathered in a sole study, and the selection of the control group. In relation to this issue, and based on genetic markers, we found that the Chilean group of breast cancer families in this study has a stronger European genetic component than our control sample selected randomly from the Chilean population.
- ItemBreast lesions with atypia in percutaneous biopsies, managed with surgery in the last 10 years(2019) Carrillo, Mitzy; Maturana, Gregorio; Maiz, Cristobal; Romero, Diego; Dominguez, Francisco; Oddo, David; Villarroel, Alejandra; Razmilic, Dravna; Elena Navarro, Maria; Leon, Augusto; Sanchez, Cesar; Camus, MauricioIntroduction: The optimal management of breast lesions with atypia (BLA), detected in percutaneous biopsies after screening mammograms, is a controversial issue. The aim of this paper is to compare histological diagnosis by percutaneous biopsy with the results of the surgical biopsy of these lesions and to analyse the changes to clinical approach this would imply.
- ItemContrast-enhanced mammography predicts pathological response after neoadjuvant chemotherapy in locally advanced breast cancer(2022) Canteros, Daniel; Walbaum, Benjamin; Córdova-Delgado, Miguel; Torrealba, Andrés; Reyes, Constanza; Navarro, María Elena; Razmilic, Dravna; Camus, Mauricio; Dominguez, Francisco; Navarrete, Orieta; Pinto, Mauricio P.; Pizarro, Gonzalo; Acevedo, Francisco; Sánchez, CésarIntroduction: Recently, contrast-enhanced mammography (CEM) has emerged as a reliable alternative to breast magnetic resonance imaging (MRI) for the assessment of pathological response in breast cancer patients. Our study sought to determine the diagnostic accuracy of CEM to predict pathological complete response (pCR) in patients who received neoadjuvant chemotherapy (NACT). Methods: We retrieved the medical records of patients who underwent NACT at our institution. Using post-surgery pCR, morphological evidence and CEM enhancement tumours were classified as follows: 1) radiologic complete response (rCR); 2) functional radiological complete response (frCR); and 3) non-complete response. Initially, we used multivariate analyses adjusted by clinical variables and frCR or rCR to determine which variables affected pathological response. Then, CEM diagnostic accuracy to discriminate pCR was assessed using receiver operating characteristic curves in univariate and multivariate models including either frCR or rCR. Results: A total of 48 patients were included in our study. Most patients (68.7%) were hormone receptor (HR)+ and 41.6% (20) of the patients achieved pCR. Using univariate logistic regression analyses we found that HR status, HER2 status, rCR and frCR had a significant impact on CEM diagnostic accuracy. Exploratory analyses found that CEM sensitivity was higher for HR− tumours. Multivariate logistic regression analyses found 60% sensitivity, 92.9% specificity and 79.2% accuracy in a model that included clinical variables and rCR. Conclusion: CEM is a reliable alternative to high-cost, time-consuming breast MRI that predicts pCR in patients undergoing NACT; CEM diagnostic accuracy was higher among patients who harboured HR− tumours.
- ItemFirst-line endocrine therapy for advanced breast cancer. A real-world study at a Latin American university health institution(TAYLOR & FRANCIS LTD, 2020) Walbaum, Benjamin; Acevedo, Francisco; Medina, Lidia; Bravo, M. Loreto; Merino, Tomas; Camus, Mauricio; Dominguez, Francisco; Mondaca, Sebastian; Galindo, Hector; Nervi, Bruno; Ibanez, Carolina; Madrid, Jorge; Pena, Jose; Koch, Erica; Garrido, Marcelo; Pinto, Mauricio P.; Sanchez, CesarObjective: Clinical guidelines recommend the use of endocrine therapy (ET) in advanced hormone receptor positive (HR+) human epidermal growth factor receptor type 2 negative (HER2-) breast cancer (BC) patients in the absence of visceral disease or ET resistance. Furthermore, studies indicate similar response and survival rates using ET or cytotoxic chemotherapy (CT). Methods: Herein, we assessed clinical characteristics, type of systemic therapy and survival rates of advanced HR + HER2-BC patients in our database. Results: A total of 172 advanced HR + HER2-BC patients were treated at our institution between 1997 and 2019. Sixty percent received first-line ET (4% received combined ET). Median age of this subset was 55 years (range: 30-86). Similarly, the median age of patients that received CT was 54 years (range: 21-83). Over time, 30% of patients received ET in the 2000-2005 period; this increased to 70% in the 2016-2019 period (p = .045). Overall survival (OS) was 97 months and 51 months for patients treated with ET or CT, respectively (p = .002). Conclusions: To the best of our knowledge this is the first study assessing the use of ET in Chilean advanced HR + HER2-BC patients. Several patients in our institution receive CT without indication. The increase in ET usage over time can be attributed to better and faster immunohistochemical detection methods for Estrogen Receptor (ER), changes in educational and government policies, and a wider variety of ET options. Finally, clinical trials have failed to demonstrate a substantial benefit of CT over ET in this setting.
- ItemLinfoma anaplásico de células grandes asociado a implantes mamarios diagnosticado mediante punción por aguja fina : caso clínico(2020) Carlos Misad, S.; Kenneth Walker, B.; Valbuena Mora, José Rafael; Guerra Sánchez, Claudio Alejandro; Camus, Mauricio; Ocqueteau Tachini, Mauricio; Loyola Zunino, Sandra; Zoroquiain Vélez, José Pablo
- ItemNeutrophil/lymphocyte ratio in complete blood count as a mortality predictor in breast cancer(SOC MEDICA SANTIAGO, 2016) Mimica, Ximena; Acevedo, Francisco; Oddo, David; Ibanez, Carolina; Medina, Lidia; Kalergis, Alexis; Camus, Mauricio; Sanchez, CesarBackground: The white blood cell count is one of the most sensitive markers associated with inflammation. The neutrophil/lymphocyte count ratio may be an independent factor for breast cancer mortality. Aim: To assess the predictive value of the neutrophil/lymphocyte ratio for mortality in breast cancer. Material and Methods: Review of the database of a cancer center of a University hospital. Patients with infiltrating breast cancer treated between 1997 and 2012 were selected. The pathology type and lymph node involvement were obtained from the pathology report. The expression of estrogen, progesterone and Human Epidermal Growth Factor Receptor 2 (HER2) was determined by immunohistochemistry or in situ fluorescent hybridization (FISH). The absolute peripheral neutrophil and lymphocyte counts were obtained from a complete blood count obtained at least three months before treatment. Patients were followed for a median of 61 months (range 1-171). Results: From 323 eligible patients, after excluding those in stage IV and those without an available complete blood count, 131 patients were analyzed (81 with negative receptors and 117 HER2 enriched). The neutrophil/lymphocyte ratio was similar in both types of tumors (2.1 and 1.91 respectively). Twenty two patients died during follow-up. Surviving patients with HER2 enriched tumors had a lower neutrophil/lymphocyte ratio than those who died (1.79 and 3.21 respectively, p < 0.01). In a multivariate analysis, including age, tumor stage and lymph node involvement as confounding factors, the neutrophil/lymphocyte ratio was still significantly associated with a risk of death with a hazard ratio of 2.56. Conclusions: A high neutrophil/lymphocyte ratio in the complete blood count can be a predictor of death in breast cancer.
- ItemPathological complete response to neoadjuvant chemotherapy, but not the addition of carboplatin, is associated with improved survival in Chilean triple negative breast cancer patients: a report of real world data(2021) Walbaum, Benjamin; Acevedo, Francisco; Median, Lidia; Bravo, M. Loreto; Merino, Tomas; Camus, Mauricio; Dominguez, Francisco; Mondaca, Sebastián; Galindo, Héctor; Nervi, Bruno; Ibañez, Carolina; Madrid, Jorge; Muñiz, Sabrina; Peña, José; Koch, Érica; Garrido, Marcelo; Pinto, Mauricio P.; Sánchez, CésarBackground: Breast cancer (BC) is the leading cause of cancer death for Chilean women. About 11% of cases are triple-negative (TN) BC. These are characterised by poor prognosis, higher risk of early recurrence and visceral dissemination versus other BC subtypes. Current standard treatment for early-stage non-metastatic TNBC patients consists of neoadjuvant chemotherapy (NACT) followed by surgery and radiotherapy. Pathological complete response (pCR) to NACT is associated with an increase in survival rates. In general, NACT and adjuvant regimens involve similar cytotoxic drugs. Recent studies have postulated that the use of platinum compounds in TNBC would increase response rates. However, their effects on patient survival remain uncertain. Materials and methods: We retrieved and analysed medical records from a total of 156 Chilean stage I–III TNBC female patients that received NACT and compared survival rates using carboplatin (Cb)-containing versus non-Cb-containing regimens at two health cancer centres. Results: Median age was 51 years (range: 24–81); 13.5% (n = 21) received Cb-containing regimens, 80.1% (n = 125) received sequential anthracyclines plus taxanes; 29.5% (n = 46) of the total group achieved pCR, 28% for the standard treatment and 35% (n = 8) for the Cb-containing group (p = 0.59). We confirmed pCR was associated with prolonged overall survival, invasive and distant disease-free survival (Log-rank p = 0.0236). But the addition of Cb was not associated with differences in survival measures (Log-rank p = 0.5216). Conclusions: To the best of authors’ knowledge, this is the first report on real-world data in the Chilean population assessing the effect of Cb-containing NACT in TNBC. The authors’ results suggest no survival benefit by the addition of Cb to standard NACT. However, we confirm an increase in survival associated to pCR regardless of treatment.
- ItemPromoter hypermethylation of BRCA1 correlates with absence of expression in hereditary breast cancer tumors(TAYLOR & FRANCIS INC, 2008) Tapia, Teresa; Smalley, Susan V.; Kohen, Paulina; Munoz, Alex; Solis, Luisa M.; Corvalan, Alejandro; Faundez, Paola; Devoto, Luigi; Camus, Mauricio; Alvarez, Manuel; Carvallo, PilarGermline mutations in BRCA1 account for a low proportion of hereditary cases in diverse populations. Several efforts have been made to find new genes involved in the inheritance of breast cancer with no success until today. The participation of BRCA1 in the development of breast cancer has been proposed in several studies where hypermethylation of its promoter and a decrease in expression has been reported for sporadic cases and one study on familial cases. To explore the participation of BRCA1 in hereditary carcinogenesis through a different mechanism than the inheritance of germline mutations, we studied the methylation status of its promoter in breast tumors, from patients previously screened for BRCA1/BRCA2 germline mutations. We also determined the presence of the BRCA1 protein in these tumors and correlated both events with tumor grade, hormone receptors and ERBB2 presence. Promoter hypermethylation of the BRCA1 gene was detected in 51% of our biopsies, among which 67% did not express the respective protein. This result leads us to suggest that hypermethylation could be considered as an inactivating mechanism for BRCA1 expression, either as a first or second hit. Moreover, a number of biopsies with absence of expression on BRCA1 showed negative detection of estrogen and progesterone receptors, a similar phenotype to BRCA1 mutated breast tumors.
- ItemScreen-detected breast cancer is associated with better prognosis and survival compared to self-detected/symptomatic cases in a Chilean cohort of female patients(2021) Walbaum, Benjamin; Puschel, Klaus; Medina, Lidia; Merino, Tomas; Camus, Mauricio; Razmilic, Dravna; Navarro, Maria Elena; Dominguez, Francisco; Cordova‑Delgado, Miguel; Pinto, Mauricio P.; Acevedo, Francisco; Sánchez, CésarPurpose The implementation of national breast cancer (BC) screening programs in Latin America has been rather inconsistent. Instead, most countries have opted for “opportunistic” mammogram screenings on the population at risk. Our study assessed and compared epidemiological, clinical factors, and survival rates associated with BC detected by screening (SDBC) or self-detected/symptomatic (non-SDBC) in Chilean female patients. Methods Registry-based cohort study that included non-metastatic BC (stage I/II/III) patients diagnosed between 1993 and 2020, from a public hospital (PH) and a private university cancer center (PC). Epidemiological and clinical data were obtained from medical records. Results A total of 4559 patients were included. Most patients (55%; n = 2507) came from PH and were diagnosed by signs/ symptoms (non-SDBC; n = 3132, 68.6%); these patients displayed poorer overall (OS) and invasive disease-free survival (iDFS) compared to SDBC. Importantly, the proportion of stage I and “luminal” BC (HR + /HER2 −) were significantly higher in SDBC vs. non-SDBC. Finally, using a stage/subset-stratified age/insurance-adjusted model, we found that nonSDBC cases are at a higher risk of death (HR:1.75; p < 0.001). In contrast, patients with PC health insurance have a lower risk of death (HR: 0.60; p < 0.001). Conclusion We confirm previous studies that report better prognosis/survival on SDBC patients. This is probably due to a higher proportion of stage I and luminal-A cases versus non-SDBC. In turn, the survival benefit observed in patients with PC health insurance might be attributed to a larger proportion of SDBC. Our data support the implementation of a systematic BC screening program in Chile to improve patient prognosis and survival rates.
- ItemSurgical treatment in oligometastatic breast cancer(2019) Vargas, Catalina; Maiz, Cristobal; Elena Navarro, Maria; Oddo, David; Sanchez, Cesar; Bustos, Marisa; Camus, MauricioMetastatic breast cancer (MBC) management is based on systemic treatment (ST), while the local therapy role remains controversial. We present the case of a 36-year-old woman with a diagnosis of hormone receptor-positive and human epidermal growth factor receptor type 2-positive breast cancer and isolated sternal metastasis, who received neoadjuvant ST with complete remission and later primary tumour surgery. Oligometastatic patients are a subgroup of MBC that can benefit from aggressive local therapies, even with curative intent.
- ItemSurvival rates of advanced estrogen-receptor positive breast cancer. Analysis of 211 cases(2020) Sanchez, Cesar; Dominguez, Francisco; Galindo, Hector; Camus, Mauricio; Oddo, David; Villarroel, Alejandra; Razmilic, Dravna; Pena, Jose; Elena Navarro, Maria; Medina, Lidia; Merino, Tomas; Briones, Juan; Acevedo, FranciscoBackground: About 80% of breast cancer (BC) cases express estrogen receptor (ER), which has been correlated with good prognosis and response to estrogen deprivation Aim: To characterize ER positive advanced BC (ABC) patients treated at our institution assessing the impact of clinical presentation (stage IV, de novo disease at diagnosis versus systemic recurrence) and BC subtype on survival rates. Material and Methods: We evaluated 211 ER+ advanced BC (ABC) patients, treated between 1997 and 2017. Results: The median overall survival (OS) was 37 months. Median OS for the period 1997/2006 and 2007/2017 were 33 and 42 months, respectively (p = 0.47). Luminal A, ABC stage IV disease at diagnosis displayed better OS rates than Luminal B stage IV tumors (100 and 32 months respectively, p < 0.01). Conclusions: Clinical presentation (stage IV vs. systemic recurrence) and tumor subtype are key determinants of OS in ABC.