Estrogen and progesterone receptor testing in breast carcinoma: concordance of results between local and reference laboratories in Brazil / Teste de receptores de estrógeno e progesterona em carcinoma de mama: concordância dos resultados entre laboratórios locais e de referência no Brasil

CONTEXT AND OBJECTIVE: Breast cancer accounts for approximately one quarter of all cancers in females. Estrogen and progesterone receptor testing has become an essential part of the clinical evaluation of breast carcinoma patients, and accurate results are critical in identifying patients who may benefit from hormone therapy. The present study had the aim of investigating the concordance of the results from hormone receptor tests between a reference laboratory and local (or community) laboratories in Brazil. DESIGN AND SETTING: Retrospective study at a reference pathology laboratory. METHODS: The concordance in the results from hormone receptor tests between a reference laboratory and 146 local laboratories in Brazil was compared in relation to 500 invasive breast carcinoma cases, using immunohistochemistry. RESULTS: There was concordance in 89.4 percent (447/500 cases) and 85.0 percent (425/500 cases) of the results from estrogen (κ = 0.744, P < 0.001) and progesterone (κ = 0.688, P < 0.001) receptor tests, respectively, between local and reference laboratories. This was similar to findings in other countries. The false negative rates from estrogen and progesterone receptor tests in local laboratories were 8.7 percent and 14.4 percent, respectively. The false positive rates from estrogen and progesterone receptor tests in local laboratories were 15.5 percent and 16.0 percent, respectively. CONCLUSION: Technical and result interpretation issues may explain most of the discordances in hormone receptor testing in local laboratories. Validation of estrogen and progesterone receptor tests at local laboratories, with rigorous quality control measures, is strongly recommended in order to avoid erroneous treatment of breast cancer patients.

CONTEXTO E OBJETIVO: O carcinoma de mama é responsável por cerca de um quarto de todos os cânceres em mulheres. O teste de receptores de estrógeno e progesterona se tornou parte essencial da avaliação clínica de pacientes com carcinoma de mama; assim, resultados precisos são fundamentais para identificação de pacientes que podem se beneficiar da terapia hormonal. O presente estudo tem por objetivo investigar a concordância nos resultados do teste de receptores hormonais entre um laboratório referência e laboratórios locais (ou comunitários) do Brasil. TIPO DE ESTUDO E LOCAL: Estudo retrospectivo em laboratório referência em patologia no Brasil. MÉTODOS: A concordância nos resultados dos testes de receptores hormonais entre um laboratório referência e 146 diferentes laboratórios locais brasileiros foi comparada em 500 casos de carcinoma invasivo de mama através da imunoistoquímica. RESULTADOS: Houve concordância de 89,4 por cento (447/500 casos) e 85,0 por cento (425/500 casos) nos resultados dos testes de receptores de estrógeno (κ = 0,744, P < 0,001) e progesterona (κ = 0,688, P < 0,001), respectivamente, entre laboratórios locais e referência, similar à descrita em outros países. A taxa de resultados falso-negativos nos testes de receptores de estrógeno e progesterona em laboratórios locais foi de 8,7 por cento e 14,4 por cento, respectivamente. A taxa de resultados falso-positivos nos testes de receptores de estrógeno e progesterona em laboratórios locais foi de 15,5 por cento e 16,0 por cento, respectivamente. CONCLUSÃO: Questões técnicas e de interpretação dos resultados podem explicar a maior parte das discordâncias nos testes de receptores hormonais em laboratórios locais. A validação dos testes de receptores de estrógeno e progesterona pelos laboratórios locais com medidas de controle de qualidade rigorosas é fortemente recomendada de modo a evitar o tratamento errôneo de pacientes com carcinoma de mama.

Pediatric lymphomas in Brazil

OBJECTIVE: This study provides the clinical pathological characteristics of 1301 cases of pediatric/adolescent lymphomas in patients from different geographic regions of Brazil. METHODS: A retrospective analyses of diagnosed pediatric lymphoma cases in a 10-year period was performed. We believe that it represents the largest series of pediatric lymphomas presented from Brazil. RESULTS: Non-Hodgkin lymphomas represented 68 percent of the cases, including those of precursor (36 percent) and mature (64 percent) cell origin. Mature cell lymphomas comprised 81 percent of the B-cell phenotype and 19 percent of the T-cell phenotype. Hodgkin lymphomas represented 32 percent of all cases, including 87 percent of the classical type and 13 percent of nodular lymphocyte predominant type. The geographic distribution showed 38.4 percent of the cases in the Southeast region, 28.7 percent in the Northeast, 16.1 percent in the South, 8.8 percent in the North, and 8 percent in the Central-west region. The distribution by age groups was 15-18 years old, 33 percent; 11-14 years old, 26 percent; 6-10 years old, 24 percent; and 6 years old or younger, 17 percent. Among mature B-cell lymphomas, most of the cases were Burkitt lymphomas (65 percent), followed by diffuse large B-cell lymphomas (24 percent). In the mature T-cell group, anaplastic large cell lymphoma, ALK-positive was the most prevalent (57 percent), followed by peripheral T-cell lymphoma, then not otherwise specified (25 percent). In the group of classic Hodgkin lymphomas, the main histological subtype was nodular sclerosis (76 percent). Nodular lymphocyte predominance occurred more frequently than in other series. CONCLUSION: Some of the results found in this study may reflect the heterogeneous socioeconomical status and environmental factors of the Brazilian population in different regions.