Figure 2From: ‘Hot cross bun’ sign with leptomeningeal metastases of breast cancer: a case report and review of the literature Presence of tumor cells present in the cerebrospinal fluid. A papanicolaou-stained, liquid-based, thin-layer preparation of cerebrospinal fluid is shown (400×). Tumor cells were of various large sizes, appeared clustered together, and had abnormal ratios of nucleus (dark blue) to cytoplasm (light blue). The features suggested adenocarcinoma cells.Back to article page