A Method of Staining Nucleoli of Cells in Fresh Benign and Malignant Tissues*

With the increasing interest in the diagnosis of malignant cells in various exudates and body fluids, a method demonstrating certain nucleolar changes in considerable detail may be of value. I t is t he purpose of this paper to present such a method and to discuss briefly the nucleolar changes in benign and malignant tissues and also to point out the potential applicability of this method as an aid in the diagnosis of cancer. The azure C method is based on the observation that nucleoli of cells of fresh tissues when exposed to certain dyes, stain electively. Naegeli (17, I8) states that the nucleoli of lymphocytes and myeloblasts often stain well with supravital technics as described by Pappenheim, Nakanishi, Sabrazes, Schilling-Torgau and Cesaris-Demel. These methods utilize methylene blue, brilliant cresyl blue or Giemsa stain. Quensel (21, 22), in particular, has studied the nucleoli of malignant cells in pleural and ascitic fluids using a staining mixture of methylene-blue-cadmium and Sudan III-cadmium. He states that with his method the nucleoli stain better than with any other method. MacCarty (13, 14), and MacCarty and Haumeder (15), in extensive work on the nucleoli and the nuclear-nucleolar ratio of benign and malignant cells, recommend Terry's or Unnas' polychrome methylene blue for the staining of these bodies in frozen sections. MacCarty states that the nucleolus may be better demonstrated in fresh tissues than in fixed tissues. Guzman (7, 8), in a study of the nucleoli of lymphocytes and monocytes of the peripheral blood, developed a method utilizing diluted Leishman or Giemsa stain. Von Haam and Alexander (25, 26), in their work on the cytology of malignant tumors, developed a method of staining nucleoli of fresh unfixed cells in suspension, with high dilutions (1 : 10,000) of toluidine blue. In most of the methods mentioned above, methy-