Motohiko Ito

Alpha‐fetoprotein and human chorionic gonadotropin‐producing lung cancer

A 73‐year‐old man had primary lung cancer that produced both alphafetoprotein (AFP) and human chorionic gonadotropin (HCG). The preoperative serum AFP level of 1039 ng/ml decreased to the normal range 8 weeks after surgery. The preoperative serum HCG level of 11 mIU/ml, which temporarily decreased to the normal range after operation, soon increased thereafter. The serum HCG level decreased, however, to the normal range after postoperative mediastinal radiation therapy. During relapse, only the serum HCG level increased gradually to 26,000 mIU/ml 7 weeks before his death. The lung cancer was classified histologically as poorly differentiated adenocarcinoma. Immunohistochemically, AFP was detected in the mononuclear tumor cells of the primary tumor in the lung, and HCG was found in the giant cells of the subcarinal metastatic lymph node. The concanavalin A non‐reactive fraction rate for AFP was 81.3%, and appeared to differ from those of hepatocellular carcinoma and yolk sac tumor. Cancer 59:227–232, 1987.

The abnormal occurrence and the differentiation-dependent distribution of N-acetyl and N-glycolyl species of the ganglioside GM2 in human germ cell tumors a study with specific monoclonal antibodies

Human primary germ cell tumors were analyzed for the presence of the ganglioside GM2 using three specific monoclonal antibodies which can distinguish the molecular species of the sialic acid moiety: the antibody MK1‐16 is specific for N‐acetyl GM2, MK2‐34 is specific for N‐glycolyl GM2, and MK1‐17 detects both N‐acetyl and N‐glycolyl GM2. When the occurrence of the GM2 antigen was tested in 107 cases of human germ cell tumors by the immunohistochemical technique using these antibodies, seminoma was characterized as having the highest frequency of N‐acetyl GM2 (89.4%, 42 of 47 cases) among germ cell tumors, followed by embryonal carcinoma (40.0%), and teratocarcinoma (26.6%). Compared with this, yolk sac tumors and choriocarcinoma had a much lower positive incidence of the N‐acetyl GM2 antigen. On the other hand, the N‐glycolyl GM2 antigen was not found at all in 47 cases of seminoma (0%), and the positive incidence was very low in embryonal carcinoma (6.6%), although considerably higher incidences were obtained with choriocarcinoma (25.0%), yolk sac tumor (22.2%), and teratocarcinoma (13.3%). The presence and molecular species of the GM2 antigens in these human germ cell tumors were also ascertained chemically by the thin‐layer chromatography (TLC) immunostaining of the ganglioside fractions prepared from primary germ cell tumors. These results indicate that seminoma specifically contains N‐acetyl GM2 and no N‐glycolyl GM2, suggesting that N‐acetyl GM2 could be a good marker for seminoma. On the other hand, non‐seminomatous germ cell tumors were characterized by the presence of N‐glycolyl GM2, one of the Hanganutziu‐Deicher antigens (H‐D antigens). Moreover, the positive occurrence of N‐glycolyl GM2 correlated very well with the degree of differentiation of non‐seminomatous germ cell tumors, i.e., the differentiated tumors such as yolk sac tumors, choriocarcinoma, and teratocarcinoma had a higher positive incidence of N‐glycolyl GM2 type H‐D antigen but a lower positive incidence of N‐acetyl GM2 when compared with embryonal carcinoma, the most undifferentiated tumors among non‐seminomatous germ cell tumors.

Lymphocyte subsets in human thymoma studied with monoclonal antibodies

Lymphocyte subsets were investigated using OKT series monoclonal antibodies and flowcytometry in 16 cases of thymoma. From the viewpoint of lymphocyte subsets, thymoma could be divided into three types: thymus lymphocyte type, peripheral lymphocyte type, and intermediate type. In thymus lymphocyte type, the number of OKT‐6+ cells exceed that of OKT‐3+ cells, and are more than 50%. In peripheral lymphocyte type, the number of OKT‐6+ cells are less than that of OKT‐3+ cells and less than 10%. In intermediate type, OKT‐6+ cells are between 10% and 30%. These three types correlate well with the histologic features with respect to the number and distribution of lymphocytes in thymoma tissue. Lymphocytes were infiltrating abundantly and intermingled in the tumor cell nests in thymus lymphocyte type, and were infiltrating rather scantly and outside the nests in peripheral lymphocyte type.

A case of solitary bronchial papilloma.

非常にまれな孤立性気管支乳頭腫の1例を経験した.症例は43歳, 女性.咳漱, 血疾を主訴とし, 胸部X線上右S6に塊状陰影を認めた.気管支鏡検査では右B6bはポリープ状の腫瘍で閉塞しており, 生検組織診断は乳頭腫の疑い, 洗浄細胞診では高分化扁平上皮癌を疑った.肺癌に準じて右下葉切除を施行した.腫瘍は5.0×5.0×3.0cm大で, 嚢胞状に拡張した右B6bに充満しており, 末梢肺は無気肺を呈していた.組織学的には気管支粘膜部に発生した分化のよい扁平上皮細胞の乳頭状増殖で, 浸潤増殖は認めず配列極性は保たれており乳頭腫と診断した.喀疾細胞診では炎症による軽度異型扁平上皮化生と診断したが, 気管支洗浄液中には重積性著明でmonotonousな細胞集塊を認め, 明らかに腫瘍性増殖集塊と考えられた.それらの細胞異型は軽度であったが構造異型を重視し, 高分化扁平上皮癌を疑った.孤立性気管支乳頭腫の細胞学的診断は喀疾細胞像のみでは困難であるが, 気管支鏡による積極的な細胞採取を行い腫瘍性増殖像を認めれぼ可能であると考えられた.

Lactate dehydrogenase isoenzyme-1 in the mediastinal yolk sac tumor

LDH isozymes in both the serum and tumor tissues of 4 patients with mediastinal yolk sac tumors, and in the cystic content of tumors transplanted into nude mice was examined. Our findings suggested that LDH-1, along with AFP, is an important marker of this tumor, and that LDH isozyme study is necessary for its diagnosis.