César Sánchez R

Obesidad y cáncer: la tormenta perfecta

While some genetic factors may explain the development of cancer, its main causes are related to environmental exposure to carcinogenic agents as well as to the effect of determined lifestyles and habits. Several epidemiological studies have shown a consistent relation between obesity and cancer. In non smokers, obesity is the most relevant risk factor in the development of malignant tumors. There is a clear association between obesity and endometrial cancer, breast cancer in postmenopausal women, pancreatic, esophageal and colon cancer. Sexual steroids, insulin like growth factor axis and adipokines are the three main models to explain the biological basis for the obesity-cancer relationship. However, these models do not explain all the biological mechanisms that link obesity to cancer. There are other factors in play such as chronic inflammation, hypoxia and oxidative stress. Obesity may hamper the screening, diagnosis and treatment of some tumors, increasing mortality rates. Obesity prevention and management, therefore, may be the most important modifiable factor in reducing both incidence and mortality in cancer. New studies are required to quantify the effect of intentional weight reduction on the incidence and relapse of cancer. Considering the efficacy of bariatric surgery for weight reduction, it is an attractive model to study this link.

Cáncer de mama metastásico: Caracterización de una cohorte según subtipos

Background: The prognosis of breast cancer (BC) is in part determined by the stage at diagnosis and its pathological characteristics. Aim: To evaluate the association between survival of women with metastatic breast cancer and pathological features of the tumor. Patients and Methods: We obtained clinical and pathological data from patients diagnosed with a metastatic BC between 1999 and 2013. The expression of estrogen(ER) and progesterone (PR) receptors and human epidermal growth factor receptor 2 (HER2) was determined by immunohistochemistry. Clinicopathological subtypes were defined as: Luminal A: ER or PR positive, HER2 negative, histological grade (HG) 1 or 2; Luminal B: ER or PR positive, HER2 negative or positive or HG 3; triple negative (TN): ER, PR and HER2 negative, independent of the HG, positive HER2: ER, PR negative and HER2 positive, independent of HG. We analyzed survival based on these subtypes. Results: We identified 54 patients aged 24 to 85 years, with metastatic BC at diagnosis. Seventy five percent had luminal tumors; 19.6% HER2 positive and 7.8% were TN. In 61% of evaluable tumors, HG was classified as 3. The frequency of HER2 positive and high HG tumors was greater in these patients with metastatic BC than in a non-metastatic local BC cohort. Survival was higher among patients with Luminal tumors than in women with non-Luminal cancer (56.4 and 11.4 months, respectively, p = 0.04). Conclusions: Patients with metastatic BC at diagnosis often had HER2 positive tumors and high HG. As in other studies, ER positive tumors had a better survival.BACKGROUND The prognosis of breast cancer (BC) is in part determined by the stage at diagnosis and its pathological characteristics. AIM To evaluate the association between survival of women with metastatic breast cancer and pathological features of the tumor. PATIENTS AND METHODS We obtained clinical and pathological data from patients diagnosed with a metastatic BC between 1999 and 2013. The expression of estrogen (ER) and progesterone (PR) receptors and human epidermal growth factor receptor 2 (HER2) was determined by immunohistochemistry. Clinicopathological subtypes were defined as: Luminal A: ER or PR positive, HER2 negative, histological grade (HG) 1 or 2; Luminal B: ER or PR positive, HER2 negative or positive or HG 3; triple negative (TN): ER, PR and HER2 negative, independent of the HG, positive HER2: ER, PR negative and HER2 positive, independent of HG. We analyzed survival based on these subtypes. RESULTS We identified 54 patients aged 24 to 85 years, with metastatic BC at diagnosis. Seventy five percent had luminal tumors; 19.6% HER2 positive and 7.8% were TN. In 61% of evaluable tumors, HG was classified as 3. The frequency of HER2 positive and high HG tumors was greater in these patients with metastatic BC than in a non-metastatic local BC cohort. Survival was higher among patients with Luminal tumors than in women with non-Luminal cancer (56.4 and 11.4 months, respectively, p = 0.04). CONCLUSIONS Patients with metastatic BC at diagnosis often had HER2 positive tumors and high HG. As in other studies, ER positive tumors had a better survival.

Rendimiento de la biopsia intraoperatoria por congelación en el estudio del linfonodo centinela en cáncer de mama

Introduccion: La biopsia del linfonodo centinela (LC) se ha convertido en la tecnica estandar para estadificar el compromiso axilar en el cancer de mama. El diagnostico intraoperatorio del compromiso metas-tasico del linfonodo permite decidir en forma inmediata la necesidad de diseccion axilar. El objetivo general de este estudio fue determinar el rendimiento de la biopsia intraoperatoria por congelacion en la pesquisa de metastasis en el LC, en pacientes con cancer de mama, entre 1999 y 2011. Material y Metodos: Estudio retrospectivo de las pacientes operadas por cancer de mama invasor, en que se realizo biopsia del LC, con estudio intraoperatorio por congelacion. Resultados: 503 pacientes con biopsia del LC con estudio intrao-peratorio. Ciento cincuenta y cuatro (30,6%) pacientes tuvieron metastasis en el LC, de estos 103 (66,9%) fueron detectadas en la biopsia rapida. No hubo diferencias significativas en la capacidad de deteccion para los tumores de hasta 2 cm y los tumores mayores de 2 cm (p = 0,86). La sensibilidad, especificidad, valor predictivo positivo (VPP) y valor predictivo negativo (VPN) de la biopsia intraoperatoria para la deteccion de metastasis en el LC fue de 66,9%, 99,7%, 99% y 87%, respectivamente. Conclusiones: El rendimiento obtenido es comparable al descrito en la literatura, siendo efectiva solo para la pesquisa de macrometastasis (MA). Dada la baja frecuencia de metastasis en el LC en tumores de hasta 2 cm, asociado a un numero relativamente alto de micro (MI) y submicrometastasis (SM) y de falsos negativos, nos parece que, en estos casos, la utilizacion de la biopsia intraoperatoria del LC es innecesaria.

IMPACTO DE LAS METÁSTASIS DEL LINFONODO CENTINELA Y SU TAMAÑO, EN EL TRATAMIENTO DEL CÁNCER DE MAMA

Impact of sentinel lymph node metastases in the treatment of breast cancer Introduction: The importance of sentinel lymph nodes (SL) metastasis at breast cancer patients has been questioned and observation without axillary dissection (AD) associated with adjuvant therapies has been the recommendation in recent years. Objective: To evaluate the macro (MA), micro (MI) and submicrome- tastasis (SM) of breast cancer in SL, and their impact on the posterior AD. Methods: We reviewed results of biopsies from patients with invasive breast cancer with MA, MI and SM found in the SL operated at our institution between May 1999 and December 2011. Results: We found 134 patients with MA, 33 patients with MI and 30 patients with SM, in a total of 632 patients with invasive breast cancer in those who underwent SL. These were operated 130, 24 and 17 patients respectively. The frequency of no sentinels lymph nodes (NSL) with metastases found on AD was 46.9% (61/130) for MA, 33.3% (8/24) for MI and 23.5% (4/17) for SM. The NSL metastasis from MA modified the TNM in 26.9% (35/130), those from MI in 20.8% (5/24) patients, while the SM only modified in one patient (5.9%). Conclusions: The frequency of lymph nodal involvement in AD is significantly higher in patients with MA. The number of AD without clear therapeutic input is high and increases with decreasing size of SL metastases. The results support to not perform AD in patients with MI and SM in the SL, who received conservative surgery and adjuvant therapy.

Cáncer de mama en mujeres adultas mayores, características clínicas e histopatológicas y resultados del tratamiento con intención curativa

BACKGROUND Aging is the main risk factor to acquire breast cancer (BC). Nevertheless BC in elderly patients is sub-represented in clinical trials. AIM To describe the clinical characteristics and long term treatment results of localized BC in older women. MATERIAL AND METHODS Review of medical records of 65 women aged 70 to 88 years, with localized BC, treated with surgery, postoperative radiotherapy or systemic therapy at a Clinical Hospital in Chile. RESULTS The presence of symptoms or abnormal findings on physical examination were the main reasons for consulting in 65% of cases. Compared with tumors detected on physical examination, those detected using screening mammogram were smaller and were in stage 1 with a higher frequency (18 and 59% respectively, p < 0.01). The pathological type was luminal in 80% of cases. Overall survival was better for luminal pathological type. All patients completed radiotherapy without interruptions developing minor acute toxicity. The most common co-morbidity was high blood pressure occurring in 46% of patients. Thirteen percent of patients had three or more co-morbidities. After a median follow up of 7 years, 23 (35%) patients had died and the cause of death was BC in 43% of cases. Two patients died of lung cancer. No patient had a local breast relapse. CONCLUSIONS Screening mammogram in older women detected smaller tumors and it was associated with a better survival. BC is the ultimate cause of death in approximately half of cases.Background: Aging is the main risk factor to acquire breast cancer (BC). Nevertheless BC in elderly patients is sub-represented in clinical trials. Aim: To describe the clinical characteristics and long term treatment results of localized BC in older women. Material and Methods: Review of medical records of 65 women aged 70 to 88 years, with localized BC, treated with surgery, postoperative radiotherapy or systemic therapy at a Clinical Hospital in Chile. Results: The presence of symptoms or abnormal findings on physical examination were the main reasons for consulting in 65% of cases. Compared with tumors detected on physical examination, those detected using screening mammogram were smaller and were in stage 1 with a higher frequency (18 and 59% respectively, p < 0.01). The pathological type was luminal in 80% of cases. Overall survival was better for luminal pathological type. All patients completed radiotherapy without interruptions developing minor acute toxicity. The most common co-morbidity was high blood pressure occurring in 46% of patients. Thirteen percent of patients had three or more co-morbidities. After a median follow up of 7 years, 23 (35%) patients have died and the cause of death was BC in 43% of cases. Two patients died of lung cancer. No patient had a local breast relapse. Conclusions: Screening mammogram in older women detected smaller tumors and it was associated with a better survival. BC is the ultimate cause of death in approximately half of cases.

¿Es curable el cáncer de mama en etapa precoz?: Resultados del tratamiento combinado con cirugía, radioterapia y quimioterapia

Background: Breast cancer will develop in one out of ten women during their lifetime. Early diagnosis has increased in recent years. Aim: To describe a population of women with breast cancer stage T1N0M0. To analyze radiation therapy toxicity and to evaluate treatment results. Material and methods: Retrospective review of the medical records of 125 women (aged 35 to 80 years) with breast cancer T1N0M0, that were treated between January 1997 and May 2004, with breast conserving surgery and postoperative radiation therapy at an oncology center. Patients lost from follow up were contacted by telephone. Results: An abnormal screening mammography was the reason for consult in 62% of cases. The average tumor size was 11.6 mm. Tumors detected with screening mammogram were smaller than those detected on physical exam. The most common radiotherapy toxicity was erithema, which was severe in 2.5% of cases. No patient had to stop the radiation treatment due to toxicity. One patient developed arm edema. Tamoxifen was prescribed for 5 years to 80% of patients and 17 patients received chemotherapy. After an average follow up of 40 months, no patient has developed local breast relapse, three patients developed contralateral breast cancer and three developed distant metastasis. Two patients died from breast cancer. Disease free survival was 95%. Conclusions: Radiotherapy was well tolerated and had excellent local control. Screening mammography detects small tumors. Survival is excellent for early stage breast cancer (Rev Med Chile 2007; 135: 427-35). (Key-words: Breast neoplasms; Mammography; Radiotherapy; Tamoxifen)

CARACTERÍSTICAS CLÍNICO-PATOLÓGICAS Y SOBREVIDA DE PACIENTES CON CÁNCER DE MAMA BILATERAL SINCRÓNICO

Clinicopathological features and survival of patients with bilateral synchronous breast cancer Introduction: Bilateral synchronous breast cancer (BSBC) has a variable incidence and conflicting data on prognosis. Our goal is to evaluate the characteristics and survival of patients with BSBC treated at Cancer Center of the Pontificia Universidad Catolica de Chile. Patients and Methods: Descriptive study. We identified patients treated between January 1999 and May 2013. We evaluated and compared characteristics from BSBC patients with a local cohort of non-synchronous breast cancer. Results: The incidence of BSBC was 1.8% (n = 28). Three patients were excluded because of missing data. Therefore we analyzed 25 patients (50 tumors). Median age: 50 years (33-84). The dominant tumors diagnosis was clinical in 47.6% of cases, and imaging in 90.5% of the contra-lateral non-dominant (p = 0.04). Average tumor size of invasive tumors was 2.5 cm for dominant tumor versus 1.7 cm for the non-dominant (p = 0.02). 81.4% of invasive tumors were estrogen receptor (ER) positive. Histological and subtype concordance between both tumors was 88% and 72% respectively. 54% of patients with BSBC were managed with total mastectomy versus 28.4% in the control group no BSBC (p = 0.0001). The estimated overall survival at 10 years was 76.5% in patients with no BSBC versus 62% in those with BSBC (p = 0.08). Conclusions: The BSBC is rare. Frequently they are ER positive tumors, mostly diagnosed through images and managed with less conservative surgery.

Vejez y cáncer de mama, el desafío del siglo 21

Background: Due to the increase in life expectancy in Chile, more than 10% of the population is 60 years or older. Since the incidence of most cancers increases with age, one of every two men and one in three women will develop a malignancy during their lifetime. In Chile breast cancer is the first leading cause of death from cancer among women. Its detection in postmenopausal women has steadily increased since the eighties, due to the expanded use of mammography. Less than 10% of patients participating in randomized controlled trials for the treatment of breast cancer, are older than 60 years, despite the fact that biological characteristics of breast cancer in older women are different and that most patients with breast cancer are of that age. Due to the high incidence of estrogen receptor positive tumors in this age group, most patients are candidates for hormone therapy. However, in those who need chemotherapy, therapeutic decisions are based on the existence of concomitant diseases and the tolerance to cytotoxic therapy. We review the relationship between age and cancer, the particular characteristics of breast cancer in older women and the alternatives of treatment with chemotherapy in advanced disease.

Evaluación de un modelo computacional para la indicación de quimioterapia en cáncer de mama

Resumen es: El cancer de mama es la segunda causa de muerte por cancer en mujeres en Chile. El tratamiento adyuvante con quimioterapia ha demostrado disminuir la rec...