Prognostic value of morphometry in patients with normal breast tissue or usual ductal hyperplasia of the breast

Higher densities of tumour-infiltrating lymphocytes and CD4+ T cells predict recurrence and progression of ductal carcinoma in situ of the breast

AIMS

Host immunity influences cancer progression and therapeutic response. We investigated the potential of tumour-infiltrating lymphocytes (TILs) around ductal carcinoma in situ (DCIS) in predicting recurrence and progression.

METHODS AND RESULTS

CD4, CD8, programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) expression in DCIS from 198 patients was determined by immunohistochemistry. We correlated disease-free survival (DFS), clinicopathological parameters and biomarker expression with TIL density and CD4/CD8 ratio. High TIL density was associated with high nuclear grade (P < 0.001), DCIS PD-L1 expression (P = 0.008), TIL PD-L1 expression (P < 0.001), oestrogen (ER) negativity (P < 0.001), progesterone (PR) negativity (P < 0.001), human epidermal growth factor receptor 2 (HER2) positivity (P = 0.002) and triple negativity (P = 0.001). TIL PD-L1 expression was associated with triple-negative DCIS (P = 0.028). TIL density was associated with molecular subtypes (P < 0.001). High CD4⁺ T cell density was associated with high nuclear grade (P = 0.001), microinvasion (P = 0.037), ER negativity (P < 0.001), PR negativity (P = 0.001), HER2 positivity (P = 0.004), triple negativity (P = 0.023) and PD-L1 expression in TILs (P < 0.011). High CD4/CD8 ratio was associated with PD-L1 expression in DCIS (P = 0.035) and TILs (P < 0.001). DCIS with higher TIL density disclosed worse DFS (P = 0.012) and was affirmed with multivariate analysis [95% confidence interval (CI) = 1.109-2.554, hazard ratio (HR) = 1.683, P = 0.014]. Poorer DFS for ipsilateral invasive recurrence was found for DCIS with higher CD4⁺ T cell density (P = 0.006) or CD4/CD8 ratio (P = 0.02), confirmed by multivariate analysis for the former (95% CI = 1.369-10.196, HR = 3.736, P = 0.01) and latter (95% CI = 1.311-7.935, HR = 3.225, P = 0.011).

CONCLUSION

DCIS with higher TIL density was associated with poorer prognostic parameters and predicted recurrence, while both CD4⁺ T cell density and CD4/CD8 ratio were associated with both recurrence and ipsilateral invasive recurrence.

Computational pathology to discriminate benign from malignant intraductal proliferations of the breast

The categorization of intraductal proliferative lesions of the breast based on routine light microscopic examination of histopathologic sections is in many cases challenging, even for experienced pathologists. The development of computational tools to aid pathologists in the characterization of these lesions would have great diagnostic and clinical value. As a first step to address this issue, we evaluated the ability of computational image analysis to accurately classify DCIS and UDH and to stratify nuclear grade within DCIS. Using 116 breast biopsies diagnosed as DCIS or UDH from the Massachusetts General Hospital (MGH), we developed a computational method to extract 392 features corresponding to the mean and standard deviation in nuclear size and shape, intensity, and texture across 8 color channels. We used L1-regularized logistic regression to build classification models to discriminate DCIS from UDH. The top-performing model contained 22 active features and achieved an AUC of 0.95 in cross-validation on the MGH data-set. We applied this model to an external validation set of 51 breast biopsies diagnosed as DCIS or UDH from the Beth Israel Deaconess Medical Center, and the model achieved an AUC of 0.86. The top-performing model contained active features from all color-spaces and from the three classes of features (morphology, intensity, and texture), suggesting the value of each for prediction. We built models to stratify grade within DCIS and obtained strong performance for stratifying low nuclear grade vs. high nuclear grade DCIS (AUC = 0.98 in cross-validation) with only moderate performance for discriminating low nuclear grade vs. intermediate nuclear grade and intermediate nuclear grade vs. high nuclear grade DCIS (AUC = 0.83 and 0.69, respectively). These data show that computational pathology models can robustly discriminate benign from malignant intraductal proliferative lesions of the breast and may aid pathologists in the diagnosis and classification of these lesions.

Subchronic exposure to phytoestrogens alone and in combination with diethylstilbestrol - pituitary tumor induction in Fischer 344 rats

Background

Subchronic administration of the potent pharmaceutical estrogen diethylstilbestrol (DES) to female Fischer 344 (F344) rats induces growth of large, hemorrhagic pituitaries that progress to tumors. Phytoestrogens (dietary plant estrogens) are hypothesized to be potential tumor inhibitors in tissues prone to estrogen-induced cancers, and have been suggested as "safer" estrogen replacements. However, it is unknown if they might themselves establish or exacerbate the growth of estrogen-responsive cancers, such as in pituitary.

Methods

We implanted rats with silastic capsules containing 5 mg of four different phytoestrogens - either coumestrol, daidzein, genistein, or trans-resveratrol, in the presence or absence of DES. We examined pituitary and other organ weights, blood levels of prolactin (PRL) and growth hormone (GH), body weights, and pituitary tissue histology.

Results

Blood level measurements of the administered phytoestrogens confirmed successful exposure of the animals to high levels of these compounds. By themselves, no phytoestrogen increased pituitary weights or serum PRL levels after 10 weeks of treatment. DES, genistein, and resveratrol increased GH levels during this time. Phytoestrogens neither changed any wet organ weight (uterus, ovary, cervix, liver, and kidney) after 10 weeks of treatment, nor reversed the adverse effects of DES on pituitaries, GH and PRL levels, or body weight gain after 8 weeks of co-treatment. However, they did reverse the DES-induced weight increase on the ovary and cervix. Morphometric examination of pituitaries revealed that treatment with DES, either alone or in combination with phytoestrogens, caused gross structural changes that included decreases in tissue cell density, increases in vascularity, and multiple hemorrhagic areas. DES, especially in combination with phytoestrogens, caused the development of larger and more heterogeneous nuclear sizes in pituitary.

Conclusions

High levels of phytoestrogens by themselves did not cause pituitary precancerous growth or change weights of other estrogen-sensitive organs, though when combined with DES, they counteracted the growth effects of DES on reproductive organs. In the pituitary, phytoestrogens did not reverse the effects of DES, but they did increase the sizes and size heterogeneity of nuclei. Therefore, phytoestrogens may oppose some but not all estrogen-responsive tissue abnormalities caused by DES overstimulation, and appear to exacerbate DES-induced nuclear changes.

Obesity is associated with atypia in breast ductal lavage of women with proliferative breast disease

BACKGROUND

Benign proliferative breast disease without atypia slightly increases breast cancer risk but there are currently few clinical options for breast cancer prevention in this group of women.

METHODS

We conducted a pilot study of women with a past diagnosis of proliferative breast disease with a goal to determine if the characteristics of cells obtained by breast ductal lavage were related to nutritional factors.

RESULTS

There were 57 women who enrolled. A total of 39 women yielded nipple aspirate fluid (NAF) samples and 36 underwent breast ductal lavage. Five of the lavage samples were acellular and 28 had at least 200 cells. Surprisingly, atypia was present in 11 women. Presence of atypia was associated with slight changes in morphometric features of the epithelial cells such as measures of circularity as obtained by image analysis, but the only variable significantly different in women with atypia (versus no atypia) was a higher mean body mass index. Body mass index was also significantly correlated with C-reactive protein (CRP) levels in the nipple aspirate fluid, indicating that obesity might have a pro-inflammatory effect on the breast that can contribute to increased rates of atypia.

CONCLUSIONS

Although the clinical significance of atypia in breast ductal lavage is uncertain, these results support further work on prevention of obesity as a strategy for reducing breast cancer risk.

Nuclear morphometric features in benign breast tissue and risk of subsequent breast cancer

Certain nuclear morphometric features measured in breast tumor tissue have been shown to predict the prognosis of breast cancer patients. However, the application of these features to predicting risk of breast cancer development has received little attention. We conducted a case-control study to evaluate nuclear morphometric features in benign breast tissue in association with subsequent breast cancer risk. The study was nested within a cohort of 4,888 women with a histopathologic diagnosis of benign breast disease (BBD) and involved 61 cases and 71 controls, amongst whom there were 53 matched case-control sets. Conditional logistic regression models were fitted to assess various measurements of nuclear size and nuclear shape factors in relation to subsequent breast cancer risk. In multivariate analysis, subsequent breast cancer risk was positively associated with a nuclear shape factor that takes the shortest nuclear axis and the longest nuclear axis into consideration simultaneously (highest quartile versus lowest 3 quartiles: odds ratio = 3.07, 95% confidence limits = 1.61, 5.84). In contrast, there was no alteration in subsequent breast cancer risk in association with nuclear size features and other shape factors. In conclusion, our study results suggest that the shape factor that takes both the shortest nuclear axis and the longest nuclear axis into consideration might be of value to predict subsequent development of breast cancer among women with BBD.

Ductal lavage: clinical utility and future promise

This article discusses the use of ductal lavage to enhance the tolerability, efficiency, and reproducibility of collecting breast duct epithelial cells for analysis for breast cancer risk assessment. Aspects discussed include the rationale for use of ductal lavage, identification of appropriate candidates for the procedure, clinical implications, ongoing evaluation of the procedure, and its future utility.