Tumori Journal

The investigation is based on the cytological findings in imprints, stained by the modified Papanicolaou E.A. 50 method, of 190 lymph nodes, of which 10 were normal 60 with benign diseases, 58 with malignant lymphomas and 62 with metastases. The cytological data were controlled by and correlated with histological sections. Touch preparations of lymph nodes do not present technical difficulties, are rapidly prepared and are always satisfactory. Cytological details are much better preserved and more recognizable than in histological sections but little information on lymph node organization is yielded. Imprints do not replace tissue diagnoses or even frozen sections, but under certain circumstances they may supply sufficient data for immediate diagnostic purposes, such as findings of metastatic malignant tumor cells or of Reed-Sternberg cells and their variants in lymph nodes during laparatomy for the staging of Hodgkin's disease. In addition to their supplementary diagnostic as well as teaching value, touch preparations allow minute caryological observations in malignant lymphomas. Peculiar basic nuclear structures in both well and poorly differentiated lymphocytic lymphomas and two different nuclear types in histiocytic lymphoma are described. The variations and frequency of several cell types (reticulum cells, lymphocytes, histiocytes, Reed-Sternberg and lacunar cells) in Hodgkin's disease are described and correlated with the histologic type.

The distribution of metastases in 783 post-mortem examinations for malignant primary tumors has been studied. Mechanical circulatory factors are not very important in determining the sites and extent of metastatic spread. The lungs and liver are the most common sites of blood borne metastates: but when organ weight are taken into account, they fall to the sixth and ninth places respectively. Different tumors, even when their position in the blood stream is the same, have very different metastatic patterns: blood borne metastases through the general arterial circulation of cancers of the lungs and cancers of other organs whose blood is drained by the caval or portal systems, but with metastases to the lungs, are in the ratios of 3:1.5:1 respectively.

Two-compartment diffusion chambers containing murine fibroblasts and a 5% (150 μg) or 1% (30 μg) MCA-discs were placed either in the peritoneal cavity of syngeneic adult mice or incubated in vitro. After 4–28 weeks of culture, groups of 5–6 DC's were recovered at 4 weeks intervals, the MCA discarded, and the contents individually implanted into immunodepressed syngeneic mice. The carcinogen displayed a strong cytotoxicity in vitro but not in vivo with both doses. On the whole, when 5% MCA was applied sarcomas appeared in 22/23 mice implanted with cells of the in vivo DC cultures and in 11/16 mice which received the in vitro cultured cells; with the lower dose, the in vivo induced tumors were 19/22 and the in vitro ones 6/12. In all groups the tumor outgrowth into the assay animals was inversely correlated with the time of exposure to MCA during the culture period.

In order to obtain data for setting up a rapid and relatively inexpensive method for studying the proliferation kinetics of human solid tumors, we have determined the kinetic parameters of an experimental solid tumor (Sarcoma 180). The curve of labelled mitosis after pulse labelling with ³H thymidine and the ³H and ¹⁴C thymidine double labelling technic on tumor samples incubated in vitro with the labelled precursors were used. A method of digestion of the tissue with hyaluronidase to obtain a cell suspension is described. This method allows easy identification of cells labelled with ³H or ¹⁴C thymidine. The two methods yielded reproducible results, the labelling index being 45%, and the duration of S phase 9.9 hours. The in vitro double labelling method with subsequent hyaluronidase digestion is proposed for studying the proliferation kinetics of solid malignancies.

Six cases of metastasis of malignant melanoma in the breast are described. Mammography did not differentiate these lesions from primary breast lesions.