Colon Tumor Tattooing-Derived Ink-Laden Macrophages in Peritoneal Ascitic Fluid.

INTRODUCTION: Macrophages containing exogenous pigments are commonly encountered in cytological specimens. CASE PRESENTATION: We present a case of tumor tattooing as an infrequent exogenous source of peritoneal fluid macrophagic pigment in a 76-year-old female. DISCUSSION AND CONCLUSION: Tattooing-derived ink can be a source of macrophagic pigment and should not be confused with other endogenous or exogenous pigments. The anatomical location and past medical history of the patient can aid in the diagnosis.