*2.4. Histopathological Examination*

The histopathological examination was conducted in the Histopathology Laboratory of our center by two pathologists with broad experience in breast cancer diagnostics. The greatest dimension of the tumor, necessary for determining the T descriptor in the pTNM classification apart from the macroscopic measurement, was verified histopathologically. This verification was undertaken using a microscope and the Olympus Cell Sens Dimension® software (Japan, 2013). Tumors up to 2 cm were excised whole, serially, on a cross-sectional basis with a margin of 0.2 to 0.4 cm and embedded in a paraffin block after each cross-section. Tumors measuring over 2 cm that could not fit within a single paraffin block were divided into two or more parts by making parallel cuts of the lesion. Next, they were marked in pairs with ink of the same color and the individual layers were given numbers to allow for the restoration of the largest section of the tumor. The T value of the tumor was the total of the parallel measurements of the particular parts of the lesion.
