Calcification Microstructure Reflects Breast Tissue Microenvironment

Abstract

Microcalcifications are important diagnostic indicators of disease in breast tissue. Tissue microenvironments differ in many aspects between normal and cancerous cells, notably extracellular pH and glycolytic respiration. Hydroxyapatite microcalcification microstructure is also found to differ between tissue pathologies, including differential ion substitutions and the presence of additional crystallographic phases. Distinguishing between tissue pathologies at an early stage is essential to improve patient experience and diagnostic accuracy, leading to better disease outcome. This study explores the hypothesis that microenvironment features may become immortalised within calcification crystallite characteristics thus becoming indicators of tissue pathology. In total, 55 breast calcifications incorporating 3 tissue pathologies (benign – B2, ductal carcinoma in-situ - B5a and invasive malignancy - B5b) from archive formalin-fixed paraffin-embedded core needle breast biopsies were analysed using X-ray diffraction. Crystallite size and strain were determined from 548 diffractograms using Williamson-Hall analysis. There was an increased crystallinity of hydroxyapatite with tissue malignancy compared to benign tissue. Coherence length was significantly correlated with pathology grade in all basis crystallographic directions (P < 0.01), with a greater difference between benign and in situ disease compared to in-situ disease and invasive malignancy. Crystallite size and non-uniform strain contributed to peak broadening in all three pathologies. Furthermore, crystallite size and non-uniform strain normal to the basal planes increased significantly with malignancy (P < 0.05). Our findings support the view that tissue microenvironments can influence differing formation mechanisms of hydroxyapatite through acidic precursors, leading to differential substitution of carbonate into the hydroxide and phosphate sites, causing significant changes in crystallite size and non-uniform strain.

Discrimination of Benign and Malignant Lesions in Canine Mammary Tissue Samples Using Raman Spectroscopy: A Pilot Study

“…Also, there is a well-defined phosphate band at 960 cm −1 and a much weaker carbonate band at 1070 cm −1 , both attributed to calcifications called type II, composed of calcium hydroxyapatite (HA). HA deposits occur in both benign and malignant tumors; HA is also a normal bone component, so it would be expected to be present in association with bone metaplasia [31,33]. However, the effects of demineralization during previous sample processing on the calcified areas must be carefully considered.…”

Triple Negative Breast Cancer: A Review of Present and Future Diagnostic Modalities

“…A mammogram requires a minimal dosage of radiation that does not easily penetrate the breast tissues [ 40 ]. Breast cancer diagnosis via mammograms is determined by the presence of calcifications (white spots), growth, or tumor also known as masses [ 41 ]. The main challenge is the risk of a false-negative and positive result affecting the diagnosed patient’s treatment outcome [ 42 ].…”

Multiple Pathways for Pathological Calcification in the Human Body

“…Not only the ion concentrations, but also local pH will affect supersaturation levels and crystallization—in bone, the pH is very tightly controlled by osteoblasts, [ 74 ] but some of the diversity of mineral phases in pathology could be due to pH variations. [ 214 ] Possible sources for calcium and phosphorus are the blood, the skeleton, and the intracellular content. Imbalances in ion concentrations can occur through local concentration fluctuations and/or degradation of mineralization inhibitors that regulate the free ion concentrations in blood, such as fetuin‐A, and/or in the tissue, such as matrix Gla protein (MGP).…”