Studies on the presence of particles resembling RNA virus particles in human breast tumors, pleural effusions, their tissue cultures, and milk.

Abstract

Studies on the presence of particles resembling ribonucleic acid virus particles in human breast tumors pleural effusions tissue cultures and milk are presented. Biopsies from 84 breast cancers 13 metastatic lymph nodes 3 fibroadenomas and cells from 33 pleural effusions from breast cancer patients were examined by electrom microscopy. Biopsy tissues of 157 cases of breast cancer of 7 metastatic lymph nodes and pleural effusion cells of 36 patients were cultured. Growth was seen in 47% of the cells derived from breast tumor biopsies and in 90% of the cells derived from pleural effusions but no cell line could be established. Milk specimens from 4 women with breast cancer and from 17 healthy women were also examined by electron microscopy for the presence of virus particles. Particles similar to murine type B or type C particles were found in 34 of 100 breast tumors metastatic lymph node and fibroadenoma biopsies in 2 of 33 pleural effusions in 4 of 72 tissue culture specimens and in 4 of 21 milk specimens. Small (300-500 angstrom) viruslike particles were seen in 26 of the breast cancer specimens 2 fibroadenomas 2 metastatic lymph nodes and in 3 different tissue cultures derived from 3 different breast tumor biopsies. So far no correlation has been found between the virus particles and the histological type of the tumors.