Shoichi Oboshi

PRIMITIVE NEUROECTODERMAL TUMOR (NEUROEPITHELIOMA) OF SPINAL NERVE ROOT–Report of an Adult Case and Establishment of a Cell Line–

A case of primitive neuroectodermal tumor arising in the cervical nerve root of a 28‐year‐old man is presented. Histologically, the tumor was characterised by proliferation of primitive neuroectodermal cells and formation of numerous Homer‐Wright type rosettes. A cell line (Nagal line) was established from the tumor. Electron microscopic examination of Nagai cells revealed numerous microrosette formation with microvilli‐like cytoplasmic processes projecting into the central lumina. Neurosecretory granules appeared in the cytoplasmic processes when Nagai cells were treated with dibutyryl cyclic AMP. Primitive satellite cells which completely surrounded other tumor cells with their tongue‐like slender cytoplasmic processes were also found. Histogenesis of this unique tumor was discussed comparing with the neuroblastoma of sympathetic nervous system, medulloblastoma of the central nervous system, and with the tumors induced by Adenovirus type 12 in animals. It was concluded that the tumor was neuroepithelioma derived from a primitive stem cell of neural crest origin which possesses the bipotency to differentiate toward either neuroblastic or neurilemmal line.

TUBERCULOID GRANULOMAS IN LYMPH NODES IRRADIATED FOR METASTATIC TUMORS

Following radiotherapy and chemotherapy, the original morphological pattern of a tumor can be modified to the point that the evidences of previous existence of the tumor in loco may be overlooked at the time of examination of tissue sections. Foreign body granulomas, most often associated with the keratotic cells of squamous cell carcinomas, were encountered in a series of irradiated human malignant tumors examined histologically at the Hospital of the National Cancer Center during the years 1962-1964. Granulomas variably infiltrated with foamy histiocytes were sometimes seen, and, in some instances, the lesion revealed a xanthomatous figure. Tuberculoid granulomas with central necrosis were found in five cases. These occurred in irradiated lymph nodes thought clinically to be the site of metastases. They are almost identical to fibrocaseous granulomas of tuberculosis and other specific infectious diseases, and to those produced by certain chemical agents. This paper deals with the histology of such tuberculoid granulomas that were associated with local cure of the malignant neoplasm. For comparison, the cervical lymph nodes with proven tuberculous lymphadenitis (60 cases) were examined through the courtesy of the Department of Pathology, Keio University. Similarly, the cervical lymph nodes containing cancer metastases with foci of necrosis from untreated patients (40 cases) were examined. Paraffin sections of the lymph nodes were stained with hematoxylin and eosin, Heidenhains modification of Mallorys aniline-blue collagen stain, Watanabes method for silver impregnation, periodic acid Schiff stain and Ziehl-Neelsen stain for acid-fast bacilli.