Prostate cancer tissue classification by multiphoton imaging, automated image analysis and machine learning.

Prostate carcinoma, a slow-growing and often indolent tumour, is the second most commonly diagnosed cancer among men worldwide. The prognosis is mainly based on the Gleason system through prostate biopsy analysis. However, new treatment and monitoring strategies depend on a more precise diagnosis. Here, we present results by multiphoton imaging for prostate tumour samples from 120 patients that allow to obtain quantitative parameters leading to specific tumour aggressiveness signatures. An automated image analysis was developed to recognise and quantify stromal fibre and neoplastic cell regions in each image. The set of metrics was able to distinguish between non-neoplastic tissue and carcinoma areas by linear discriminant analysis and random forest with accuracy of 89% ± 3%, but between Gleason groups of only 46% ± 6%. The reactive stroma analysis improved the accuracy to 65% ± 5%, clearly demonstrating that stromal parameters should be considered as additional criteria for a more accurate diagnosis.

Interobserver agreement of Gleason score and modified Gleason score in needle biopsy and in surgical specimen of prostate cancer.

INTRODUCTION: Gleason score, which has a high interobserver variability, is used to classify prostate cancer. The most recent consensus valued the tertiary Gleason pattern and recommended its use in the final score of needle biopsies (modified Gleason score). This pattern is considered to be of high prognostic value in surgical specimens. This study emphasized the evaluation of the modified score agreement in needle biopsies and in surgical specimen, as well as the interobserver variability of this score. MATERIALS AND METHODS: Three pathologists evaluated the slides of needle biopsies and surgical specimens of 110 patients, reporting primary, secondary and tertiary Gleason patterns and after that, traditional and modified Gleason scores were calculated. Kappa test (K) assessed the interobserver agreement and the agreement between the traditional and modified scores of the biopsy and of the surgical specimen. RESULTS: Interobserver agreement in the biopsy was K = 0.36 and K = 0.35, and in the surgical specimen it was K = 0.46 and K = 0.36, for the traditional and modified scores, respectively. The tertiary Gleason grade was found in 8%, 0% and 2% of the biopsies and in 8%, 0% and 13% of the surgical specimens, according to observers 1, 2 and 3, respectively. When evaluating the agreement of the traditional and modified Gleason scores in needle biopsy with both scores of the surgical specimen, a similar agreement was found through Kappa. CONCLUSION: Contrary to what was expected, the modified Gleason score was not superior in the agreement between the biopsy score and the specimen, or in interobserver reproducibility, in this study.

Interobserver agreement of gleason score and modified gleason score in needle biopsy and in surgical specimen of prostate cancer

INTRODUCTION: Gleason score, which has a high interobserver variability, is used to classify prostate cancer. The most recent consensus valued the tertiary Gleason pattern and recommended its use in the final score of needle biopsies (modified Gleason score). This pattern is considered to be of high prognostic value in surgical specimens. This study emphasized the evaluation of the modified score agreement in needle biopsies and in surgical specimen, as well as the interobserver variability of this score MATERIALS AND METHODS: Three pathologists evaluated the slides of needle biopsies and surgical specimens of 110 patients, reporting primary, secondary and tertiary Gleason patterns and after that, traditional and modified Gleason scores were calculated. Kappa test (K) assessed the interobserver agreement and the agreement between the traditional and modified scores of the biopsy and of the surgical specimen RESULTS: Interobserver agreement in the biopsy was K = 0.36 and K = 0.35, and in the surgical specimen it was K = 0.46 and K = 0.36, for the traditional and modified scores, respectively. The tertiary Gleason grade was found in 8 percent, 0 percent and 2 percent of the biopsies and in 8 percent, 0 percent and 13 percent of the surgical specimens, according to observers 1, 2 and 3, respectively. When evaluating the agreement of the traditional and modified Gleason scores in needle biopsy with both scores of the surgical specimen, a similar agreement was found through Kappa CONCLUSION: Contrary to what was expected, the modified Gleason score was not superior in the agreement between the biopsy score and the specimen, or in interobserver reproducibility, in this study.

Expressão de sulfomucinas e de carboidratos de mucinas simples no esôfago de Barrett / Expression of sulphomucins and simple-mucin type carbohydrate in Barrett's esophagus

INTRODUÇÃO: A expressão de mucinas sulfatadas e de antígenos de carboidratos simples de mucinas tem sido relacionada com o risco de transformação maligna no trato gastrintestinal. OBJETIVOS: Avaliar a expressão de mucinas sulfatadas e dos antígenos Tn, sTn, T e sT no esôfago de Barrett (EB). MATERIAL E MÉTODO: Estudaram-se 50 biópsias de EB. As amostras foram processadas rotineiramente para exame histológico (hematoxilina e eosina [HE] e ácido periódico de Schiff [PAS]/azul de alcião). Cortes adicionais foram corados para detecção de mucinas sulfatadas (diamina férrica) e dos antígenos Tn, sTn, T e sT por imuno-histoquímica. O EB foi classificado quanto aos subtipos de metaplasia intestinal e sua extensão nas amostras. A expressão de Tn, sTn, T e sT no EB foi discriminada quanto à positividade em células caliciformes e colunares. RESULTADOS: Detectou-se metaplasia intestinal incompleta com secreção de sulfomucinas em 47 casos; em três não se identificou a lesão nos cortes realizados para a histoquímica. Observou-se metaplasia intestinal tipo III em 44 dos 47 casos analisados (93,6 por cento) e do tipo II isoladamente em três casos (6,4 por cento). Não se detectou metaplasia intestinal do tipo I. Tn expressou-se fortemente em células colunares em 94 por cento dos casos e foi focal/negativo nas caliciformes; sTn exibiu forte marcação nas células caliciformes em 88 por cento dos casos. Os demais marcadores foram negativos na maior parte dos casos (T negativo em 82 por cento e sT em 87,8 por cento). CONCLUSÕES: A expressão de sulfomucinas e de antígenos de carboidratos simples de mucinas foi homogênea no EB. A lesão caracterizou-se por metaplasia intestinal incompleta com extenso componente de tipo III e expressão de Tn e sTn. Esses dados sugerem que os marcadores testados não permitem discriminar lesões com diferentes potenciais de transformação maligna.

BACKGROUND: The expression of sulphomucins and simple-mucin type carbohydrate antigens has been used as marker of malignant transformation in the gastrointestinal tract. OBJECTIVES: To evaluate the expression of sulphomucins and simple-mucin type carbohydrate antigens (Tn, sTn T and sT) expression in Barrett's esophagus (BE) in order to identify potential lesions of increased risk to malignant transformation. METHODS: Biopsies of 50 cases of BE processed routinely were studied; diagnosis was performed in hematoxylin and eosin (HE) and periodic acid Schiff (PAS)/alcian blue stained sections. Additional sections were stained by high iron diamine for subtype intestinal metaplasia and by immunohistochemistry for Tn, sTn, T and sT antigens, whose expression was analyzed in the columnar and goblet cells of BE. RESULTS: BE was detected in only 47 cases stained by histochemistry and all of them had sulphomucin expression. Type III intestinal metaplasia was detected in 44 cases (93.6 percent); three had only type II, and type I was not observed. Tn antigen was expressed in columnar cells in 94 percent of the cases and sTn was expressed in goblet cells in 88 percent of them. T and sT were negative in 82 percent and in 87.8 percent of the cases, respectively. CONCLUSIONS: BE showed a homogeneous pattern of expression of sulphomucins and simple-mucin type carbohydrate antigens. BE was characterized as incomplete-type intestinal metaplasia with type III component together with Tn and sTn expression. According to these data, these markers are not useful to discriminate lesions with different potential of malignant transformation.