Physicians' attitudes and perceived barriers to adherence to the national breast cancer clinical practice guidelines in Mexico: a survey study.

BACKGROUND: Adherence to clinical practice guidelines improves outcomes for patients with breast cancer. However, their implementation may not be feasible in low- and middle-income countries. This study aimed to evaluate physicians' adherence, attitudes, and barriers towards the Colima Consensus, which is the Mexican national breast cancer clinical practice guideline. METHODS: A cross-sectional, 31-item survey was e-mailed to Consensus attendees and members of the Mexican Society of Oncology and Mexican Mastology Association. Descriptive statistics, univariate, and multivariate analysis were used to analyze the associations between participants' characteristics, adherence, attitudes, and barriers. RESULTS: Of 439 respondents, 78% percent adhered to Consensus recommendations and 94% believed it was applicable to their clinical practice. Forty percent reported using the Consensus as their sole breast cancer guideline. This was associated with being a surgical oncologist (OR 3.3, 95% CI 2.0-5.3) and practicing at a public hospital (OR 2.1, 95% CI 1.2-3.7). The most common barriers to adherence were lack of resources and logistical problems. Regarding attitudes towards the Consensus, 90% considered it a good educational tool, 89% considered it a reliable source of information, and 90% thought it improved quality of care. CONCLUSIONS: We showed high levels of adherence and positive attitudes towards the Colima Consensus, with a significant proportion of physicians using it as their only guideline. Lack of resources and logistical issues were the main barriers to adherence. Our results highlight the relevance of local breast cancer guidelines and suggest a need for the creation of resource-stratified guidelines.

[Intracellular signaling mechanisms in thyroid cancer]. / Mecanismos de señalización intracelular en cáncer de tiroides.

BACKGROUND: Thyroid cancer is the most common malignancy of the endocrine system, the papillary variant accounts for 80-90% of all diagnosed cases. In the development of papillary thyroid cancer, BRAF and RAS genes are mainly affected, resulting in a modification of the system of intracellular signaling proteins known as «protein kinase mitogen-activated¼ (MAPK) which consist of «modules¼ of internal signaling proteins (Receptor/Ras/Raf/MEK/ERK) from the cell membrane to the nucleus. In thyroid cancer, these signanling proteins regulate diverse cellular processes such as differentiation, growth, development and apoptosis. MAPK play an important role in the pathogenesis of thyroid cancer as they are used as molecular biomarkers for diagnostic, prognostic and as possible therapeutic molecular targets. Mutations in BRAF gene have been correlated with poor response to treatment with traditional chemotherapy and as an indicator of poor prognosis. OBJECTIVE: To review the molecular mechanisms involved in intracellular signaling of BRAF and RAS genes in thyroid cancer. CONCLUSIONS: Molecular therapy research is in progress for this type of cancer as new molecules have been developed in order to inhibit any of the components of the signaling pathway (RET/PTC)/Ras/Raf/MEK/ERK; with special emphasis on the (RET/PTC)/Ras/Raf section, which is a major effector of ERK pathway.

Tratamiento del cáncer mamario etapa IV y recurrente / Treatment of breast cancer, stage IV and recurrens

Objetivo. Análisis y revisión del tratamiento actual de cáncer de mama en etapa IV y recurrente. Sede. Division de Padecimientos Neoplásicos y Proliferativos del Centro Médico Nacional "20 de Noviembre" del ISSSTE. Método. Evaluación de la literatura internacional (20 referencias) en relación al tema. Experiencia personal en el tema. Resultados. El cáncer mamario etapa IV y recurrente representa un reto continuo para el clínico, el empleo de quimioterapia combinada, desde hace más de 3 décadas, ha permitido una paliación excelente, pero la mayoría de las pacientes morirán por su enfermedad, lo que ocurre pocos años o meses después de la recaída, sólo un pequeño número de ellas podrá sobrevivir libre de la enfermedad por un periodo prolongado de tiempo. Las combinaciones con antracilinas constituyen el tratamiento de primera línea. Los nuevos fármacos como el navelbine, el taxan y el gemcitabine están en estudio y requieren de la prueba del tiempo para ser incluidos, en forma rutinaria, como tratamiento de primera línea. Conclusión. La elección entre hormonoterapia y quimioterapia depende de una cuidadosa evaluación individual de cada paciente, considerando que el objetivo del tratamiento es paliativo