Clinicopathologic study of 275 cases of gastrointestinal stromal tumors: the experience at 3 large medical centers in Mexico.

It is important to distinguish gastrointestinal (GI) stromal tumors (GISTs) from other GI mesenchymal tumors (GIMTs) because of the availability of molecular-targeted therapy for GISTs. The aim of the study was to reclassify GIMTs and to determine the clinicopathologic features of GISTs in Mexico. Cases of GIMT identified from the database of 3 large diagnostic centers in Mexico between 1995 and 2004 were reclassified according to current criteria. Hematoxylin and eosin-stained sections and clinical histories were reviewed, and immunohistochemistry was performed using anti-CD117, CD34, smooth muscle actin, and S-100 protein. A total of 275 GISTs were identified. The tumors were located in the stomach (40%), small intestine (35%), colorectum (12%), abdominal cavity (11%), and esophagus (2%). There were equal numbers of men and women with a mean age at diagnosis of 61 years. The tumors ranged in size from 3.5 to 34 cm (mean, 9.1 cm); 95 tumors (34%) were larger than 10 cm. Colorectal and omental tumors were the largest. The cell types included pure spindle (68%), pure epithelioid (16%), and mixed epithelioid/spindle (14%). Whereas 17.8% of tumors were regarded as low risk, 43% of tumors were in the high-risk category. CD117 positivity was detected in most of the tumors (96%). In addition to CD117, 255 cases (92%) were positive for CD34, 82 cases (32%) were positive for smooth muscle actin, and 13 cases (4.7%) were positive for desmin. Gastrointestinal stromal tumors in Mexico have the same clinicopathologic and immunohistochemical features as those reported in other countries. It is not always easy to distinguish GISTs from other soft tissue lesions. The diagnosis can be difficult even for experienced pathologists.

Motivos de abandono en el proceso de atención médica de lesiones precursoras de cáncer cervicouterino / Medical care abandon factors in precursor lesions of cervical cancer

Objective. To determine factors associated with medical care abandon of women with CIN. Material and methods. A nested case-control study in a cohort was done. Patients referred to clinical Dysplasia of Gyneco-Obstetrician Services in third level Hospitals were considered. Cases: Patients who abandoned medical care. Controls: women who attend their medical appointments during follow-up. All subjects underwent structured interviews focused on social, clinical and health services factors in two different times, applied at the beginning of study and the end of follow-up. Clinical records were reviewed to obtain clinical information. Analysis: Descriptive and inferential statistical was done. Non conditional Logistic Regression analysis was done to obtain adjusted association. Results. Abandon cumulative incidence rate was 108/525 = 20.7% (I.C 95% = 17.2-24.3); 60.2% happened in diagnosis phase, 17.7% ocured during therapeutic phase and 23.1% happened in surveillance phase. We studied 108 cases and 417 controls to analysis. Next adjusted risk factors were obtained: Afraid to death (ORa = 4.2, I.C.95% = 1.8-9.5), long appointments (ORa = 6.6, I.C95% = 3.4-13.0), lack of privacity (ORa = 12.5, I.C.95% = 2.6-59.8), reject to treatment (ORa = 40.4, I.C.95% = 2.1-785.4), lack of information (ORa = 41.9, I.C95% =14.2-124.1) and other factors. Conclusions. Patient perception, access and barriers in health services were the most important factors associated with medical care abandon.

Objetivo. Determinar factores asociados al abandono del proceso de atención de NIC. Material y métodos. Se realizó un estudio de casos y controles anidado en una cohorte de mujeres referidas a las clínicas de displasias de dos hospitales de tercer nivel. Casos: pacientes que abandonaron su atención médica. Controles: pacientes que cumplieron con sus citas médicas. Las pacientes contestaron una entrevista estructurada respecto a variables sociodemográficas y de atención médica al inicio y al final del seguimiento. Los datos clínicos se obtuvieron de la revisión de expedientes. Análisis: Medidas de frecuencia y asociación, ajustando variables con Regresión Logística no Condicionada. Resultados. La tasa de abandono fue de 108/525 = 20.7% (17.2-24.3); 60.2% ocurrieron en la fase diagnóstica, 17.7% durante el tratamiento y 23.1% en la fase de vigilancia y/o control. Un total de 108 casos y 417 controles fueron considerados para el análisis. Los factores de riesgo ajustados fueron: miedo a la muerte (ORa = 4.2, I.C.95% = 1.8-9.5), citas prolongadas (ORa = 6.6, I.C.95% = 3.4-13.0), falta de privacidad (ORa = 12.5, I.C.95% = 2.6-59.8), rechazo al tratamiento propuesto (ORa = 40.4, I.C.95% = 2.1-785.4) y falta de información (ORa = 41.9, I.C.95% = 14.2-124.1) entre otros. Conclusiones. Los factores relacionados con la percepción de gravedad de la enfermedad y las barreras al acceso de los servicios de salud fueron los de mayor importancia para abandonar la atención médica.

Micropapillary carcinoma of the urothelial tract. A clinicopathologic study of 38 cases.

Micropapillary carcinoma (MPC) of the bladder is a rare and aggressive variant of bladder carcinoma. The goals of this study are to investigate whether this variant of bladder carcinoma represents a more aggressive disease than conventional urothelial carcinoma (CUC) and to determine the incidence of MPC in our country. A total of 630 urothelial carcinomas diagnosed from 1997 to 2003 at the Department of Pathology, Oncology Hospital, in Mexico City were analyzed to identify MPC. Thirty-eight patients were found to have this diagnosis and along with a group of 76 patients diagnosed with CUC serve as the basis for this study. In 37 patients with MPC, the lesions were located in the bladder, and in 1 patient in the ureter. The mean patients' age at diagnosis was 68 years, and the male-female ratio was 37:1. The initial stage at presentation was high in most of the patients: Three patients had stage T1, 8 had stage T2, 18 had stage T3, and 9 had stage T4. The disease-specific survival rate for patients with MPC at 3.1 years was 39.5% (95% confidence interval [CI], 2.7%-3.4%) whereas for patient with CUC was 55.3% (95% CI, 3.9%-4.4%). Patients with a micropapillary component of more than 50% had a relative mortality risk of 2.4 (1.3-4.2), whereas patients with less than 50% of MPC did not have a significantly increased mortality risk (RR, 1.8; 0.5-6.0). In summary, in this study, MPC was far more aggressive clinically than CUC. In Mexico, the incidence of 6% of MPC in relation to CUC and the male-female ratio of 37.1 for MPC are much higher than reported in the literature.

[High-risk human papilloma virus and cervical intraepithelial neoplasia in women at 2 hospitals in Mexico City]. / Virus de papiloma humano de alto riesgo (VPH-AR) y neoplasia intraepitelial cervical (NIC) en mujeres de dos hospitales de la Ciudad de México.

OBJECTIVE: To determine the high risk HPV (HR-HPV) association with Cervical Intraepithelial Neoplasia (CIN) in women of two Dysplasia Clinics in Mexico City. MATERIAL AND METHODS: Prolective case-control study was done. Women with and without security affiliation attended in Instituto Mexicano del Seguro Social (Hospital 1) and Hospital General de México (Hospital 2) were included in the study. Cases were women with histopathologic diagnosis of CIN and controls were women with negative dysplasia in cytologic study (Pap). Information was obtained by direct interview. HR-HPV was determined by Hybrid Capture II assay, in cervical samples. Bivariate and logistic regression analysis was done. RESULTS: One hundred and two cases and 192 controls from Hospital 1 and 89 cases and 66 controls from Hospital 2 were included. 83.3% and 77.3% of women from Hospital 1 and 2 respectively were positive to HR-HPV. The association HR-HPV and CIN in Hospital 1 was ORa = 40.6, C.I. 95% = 17-96.8; while in Hospital 2 there was not association. Age was an effect modifier in the HR-HVP and CIN association, in Hospital 1. It was observed a correlation between viral load and CIN degree. CONCLUSIONS: The HR-HPV infection frequency in controls and CIN I was higher than the reported in other studies. Age was a modifier in the HR-HPV association and CIN. In dysplasia clinics without medical referral system of patients is possible to observe similar risk factors to cervical cancer.