Centrifugal separation of cells in sputum

Exfoliative cytologic evaluation of primary cultured lung carcinomas

This paper describes a tissue culture and exfoliative cell culture system that enables one to (1) evaluate the adequacy of primary lung carcinoma cultures for cytogenetic analysis, and (2) predict the likelihood of viable cells and type of differentiation present in the primary lung tumor cultures used for cytogenetics. Primary lung carcinomas were established from explant outgrowths and maintained in serum supplemented or serum free media on plastic or basement membrane associated protein coated dishes in order to obtain cells for karyotypic analysis (Miura et al., 1990). The media from these cultures that would ordinarily have been discarded was aspirated at each media change and used to prepare cytocentrifuge cytology preparations. Papanicolaou stained cells from the preparations were evaluated by cytotechnologists in order to assess (1) the cellularity and presence of cancer cells in the sample, (2) cytology preparations of cell and explant outgrowth cultures from primary lung tumors are reliable method for screening and evaluating the suitability of primary lung carcinoma cultures for cytogenetic analysis.

Centrifugal separation of carcinoma or atypical cells in voided urine

A simple density gradient method was used to separate atypical and cancer cells from non-cancer cells in voided urine from patients with transitional cell atypia (moderate and grave atypia) and bladder cancer (squamous cell carcinoma and transitional cell carcinoma). Prior to cell separation, the Saccomanno preserved cells were dispersed by homogenization. After cell separation (5 min x 1400 rpm), atypical and cancer cells were enriched up to 20-fold. Also, most of the leucocytes (68-98%) and squamous cells (47-82%) were absent from density gradient specimen fractions containing the largest percentages of atypical and cancer cells. Peak purity ranges of atypical or cancer cells from different sample classes showed a large degree of overlap. This permitted the pooling of density gradient fractions enriched for atypical or cancer cells, thus increasing the efficiency of the method. Also, following centrifugation, the Papanicolaou-stained specimen fractions showed less background staining than the unprocessed controls, and the cells retained diagnostic morphologic features. We infer that this method may be a useful, low-cost approach for the morphologic study of developing cancers, not only from the urinary bladder, but also from the respiratory tract.

Centrifugal separation of cells in sputum specimens from patients with undifferentiated carcinoma

Ethanol-fixed cells in sputum from patients with undifferentiated carcinoma of the lung were separated in aqueous Ficoll using a discontinuous density gradient centrifugation technique. The selective enrichment of small cell undifferentiated (e.g., oat cell) or large cell undifferentiated carcinoma cells was achieved while removing most of the leukocytes (80-90%) and macrophages (65-75%) from specimen fractions containing the greatest relative frequencies of cancer cells. The maximum purity of small cell carcinoma cells (0.04%) occurs in moderate density (rho = 1.121 g/ml) gradient fractions and results in a 2.4-fold enrichment relative to unprocessed specimens. In contrast, the maximum purity of large cell carcinoma cells (0.22%) is obtained in very high density (rho = 1.172 g/ml) gradient fractions and results in a 1.2-fold enrichment in comparison with unprocessed specimens. Microscopic examination of Papanicolaou-stained specimen fractions reveals that these enrichments were achieved while retaining diagnostically significant cytomorphologic and tinctorial features necessary for cancer screening and diagnosis. Peak purity ranges of undifferentiated cancer cells significantly overlap comparable ranges for material from bronchogenic adenocarcinoma and squamous cell carcinoma.

Centrifugal separation of cells in sputum specimens from patients with adenocarcinoma

A Ficoll density gradient centrifugation technique was used to separate fixed cells from the sputa of patients with bronchogenic adenocarcinoma. The selective enrichment of leukocytes, squamous or cancerous cells was achieved while retaining the diagnostically significant cell morphologic features. This technique is shown to typically eliminate most of the leukocytes (96.9%) macrophages (86.7%), squamous cells (70.0%) and necrotic debris from specimen fractions containing the majority of cancerous cells. The maximum purity of cancer cells (14.6%) occurs in high density (p = 1.35 g/ml) gradient fractions and results in an average 12.2-fold enrichment for cancer cells in contrast to their relative frequency of occurrence in unprocessed specimens. Differential cell count analyses of serial density centrifugation fractions show that this technique produces comparable enrichment rates for material from bronchogenic adenocarcinoma and squamous cell carcinoma.