THE STUDY OF THE HUMAN TESTES IN MALIGNANT HEMATOPOIETIC TUMORS

PARTICULARLY IN LEUKEMIA

Abstract

The human testes in cases with malignant hematopoietic tumors, especially with leukemia, were histopathologically examined. Materials were obtained from 56 autopsy cases, composed of 47 with leukemia, 7 with reticulum cell sarcoma and 2 with lymphosarcoma.
The results obtained were as follows:
1. Leukemic infiltration was confirmed in 43 (91%) of all leukemia cases. The patterns of infiltration in the testes were divided into three types; diffuse, patchy and perivascular, according to the distribution of leukemic cells. A high grade infiltration was most commonly encountered in lymphatic leukemia and observed in 3 cases (44%), while in 4 cases (10%) in others. The leukemic infiltration preferred the interstitial space without involvement of seminiferous tubules. The testicular involvement was unexceptionally bilateral with occasional differences in the grade of infiltration, slight to moderate.
2. There was no regional difference in incidence of the leukemic infiltration in the testicular interstitial tissue. However, nodular foci of leukemic cell infiltration, 500μ to 1000μ in diameter, around the middle-sized blood vessels, were observed in 10 cases but the evidence of mural penetration was not confirmed.
3. Leukemic cells were often observed in a thin-walled canal closely between the proper lamina of the seminiferous tubules and the interstitial cell cluster. The finding that the canal had endothelium along the internal wall and no red cells in the lumen suggested that it was a lymphatic vessel. Serial sectioning of the tissue with a canal revealed that the canal had an extremely irregular shape and occasionally lacked in the endothelium. It was, therefore, considered that the human testicular lymphatics might not be a constant canal system, but likely akin to narrow tissue space.
4. A network of argyrophil fibers was formed in the area of leukemic infiltration in the interstitial tissue in parallel with the severity of the lesion.
5. The testicular involvement was observed in only one of 7 cases with reticulum cell sarcoma and in one of 2 with lymphosarcoma, with the grade of infiltration lesser than that in leukemia.
It was considered that tumor cell infiltration in the testes would be mostly transported from the blood vessels into the interstitial tissue through the perivascular space and lymphatics around the seminiferous tubules. Changes of blood and lymph themselves and of their canals would be responsible for the high frequency of testicular involvement in leukemia cases particularly in lymphatic leukemia.