The level of α1FP has been evaluated in the sera of 155 children aged 1 month to 16 years with germ cell tumors. Abnormal α1FP levels were found in 63 cases. Reexamination of histological slides from more than 120 cases, in a double blind study has revealed a close connection between the presence of abnormal α1FP levels in the serum and the presence of vitelline components on the tissue sections: 54 yolk sac tumor out of 60 are α1FP positive (that is 90% and 100% in the acute phase), whatever the site: testis, ovary, vagina, sacrococcygeal, intra‐ or retro‐peritoneal region, mediastinum or intracranium. Immunohistological localization (immuno‐fluorescence and immuno‐peroxydase) was performed in this study.
Cytochemical reactions were examined in lymph node imprints from a group of 53 previously untreated patients with histologically proven Hodgkin’s disease. In 40 of 51 cases investigated, Reed-Sternberg (R-S) cells, irrespective of the cytologic appearances and the histologic types, showed moderate to strong reactions with acid phosphatase (ACP). In 12 cases ACP activity was present in more than 25% of the R-S cells. The reaction consisted of formation of small- to medium-sized granules, which were located close to the nuclei on a diffusely positive background or irregularly distributed throughout the cytoplasm. In three cases, a coarse granular reaction product with periodic acid-Schiff was present. R-S cells were positive to the naphthol-AS acetate esterase and β-glucuronidase reactions in four and two cases, respectively. Alkaline phosphatase and naphthol-AS-D-chloroacetate esterase reactions were completely negative. Our results have revealed a pattern of staining in the diagnostic R-S cells similar to that in its morphologic variants; this supports the view that these cells may derive from a common primitive cell. Moreover, the quality and quantity of the ACP reaction product shows that R-S cells differ from both neoplastic histiocytes of malignant histiocytosis and neoplastic lymphocytes of T-cell lymphomas. This study confirms that R-S cells lack definite cytochemical characteristics of each of supposed progenitor cells: histiocytes and T-lymphocytes.
Malignant histiocytosis (MH) is a true histiocytic disorder, whose identification is still based on too broad morphologic criteria. Using routine histology, cytochemical and immunohistochemical techniques on involved lymph nodes, 15 cases of MH have been investigated. Pleomorphism and cellular atypia, phagocytosis, lack of cohesiveness between proliferating cells, sinusoidal involvement, and plasmacytic infiltrate were the most common histologic features. MGG-stained imprints from 14 cases showed a composite tumor population mainly consisting of histiocyte-appearing cells, poorly differentiated atypical cells, and multinucleated giant cells. These cells, irrespective of cytologic features, revealed a diffuse, moderately to strongly positive reaction with acid phosphatase and nonspecific esterase. Naphthol-AS-D-chloroacetate esterase, Sudan black B, alkaline phosphatase, and beta-glucuronidase reactions were completely negative. Immunoperoxidase studies in 11 cases demonstrated that tumor cells stained positively for both kappa and lambda chains. These cells were also positive for albumin. Polytypic staining for IgG was observed in two cases, and a weak staining for lysozyme was found in two other nodes. Global results confirm the value of these studies for functional profile determination of MH proliferating cells. A combined approach using a variety of cytochemical and immunohistochemical techniques should be routinely considered in MH as useful additional studies for a more precise diagnostic definition of the disease.
