How do atypical cells appear under a histological examination?

Atypical cells are typically characterized by specific features that indicate abnormality in their structure and function. During a histological examination, these cells often exhibit enlarged nuclei, which can appear disproportionate to the size of the cytoplasm. These nuclei are often irregular in shape and may have an increased nuclear-to-cytoplasmic ratio, suggesting a departure from normal cell morphology that is commonly observed in healthy tissues.

The enlargement and irregularity of the nuclei are significant indicators of potential malignancy or dysfunction. Such morphological changes can result from various processes, including cancerous transformation, chronic irritation, or other pathological conditions. By recognizing these features, pathologists can assess the likelihood of neoplasia or other disease processes.

In contrast, the other options describe features associated with normal, healthy cells or specific benign conditions that do not exhibit the atypical characteristics necessary for identification as atypical cells. For instance, regularly shaped and normal-sized nuclei, small compact cells, and uniform size and shape are all indicative of healthy tissue, lacking the abnormalities seen in atypical cells.