Light and electron microscopic study of nonfunctioning parathyroid carcinoma. Report of a case with a review of the literature.

A case of nonfunctioning parathyroid carcinoma in a 69-year-old female has been studied by light and electron microscopy. The tumor, located on the left side of the anterior neck, was well encapsulated by connective tissue but showed invasion to the capsule and to the thyroid. The tumor cells exhibited a trabecular arrangement surrounded by capillary networks but focally showed several ductal structures. They were polygonal in shape, had a large nucleus showing frequent mitosis and poor cytoplasm containing glycogen. Some tumor cells had clear and abundant cytoplasm, and resembled water-clear cells of the parathyroid. Immunohistochemically, no thyroglobulin was demonstrated in the tumor tissue. Electronmicroscopically, the tumor cells with high N/C ratio contained poorly developed cell organelles and abundant glycogen particles. They were poor in secretory granules and had no conglomeration of lipid. Desmosomes and tonofibrils were observed. The ratio of the reported number of nonfunctioning parathyroid carcinoma to that of functioning one in Japan was compared with that in western countries. No difference of the ratio was found between these two, when identical criteria were employed.

Hepatic portoenterostomy for congenital biliary atresia - method of dissection of porta hepatis, evaluation of revision, re-boring and supplementary operations.

A few guidelines for surgical dissection at the porta hepatis in hepatic portoenterostomy for congenital biliary atresia as evolved from our experiences on 52 cases are suggested. Indication for revision is also shown. Supplementary procedures in case of complications, such as ascending cholangitis and the onset of portal hypertension, are also described. An early primary operation as well as a positive revision and supplementary procedures for ascending cholangitis and oesophageal varices have resulted in an improvement of the therapeutic results.

[Fine needle aspiration cytology of 637 thyroid nodules].

Fine needle aspiration cytology was performed in the preoperative evaluation of 637 thyroid nodules. Cytological findings in benign and malignant tumor were classified and compared. In 514 cases in which cells were sampled, accuracy rate, false negative rate and false positive rate of cytology was 88.0, 7.0 and 4.1%, respectively. The corresponding figures of clinical diagnosis were 82.3, 13.0 and 4.1%, respectively. Cytological diagnosis was thus more accurate than clinical diagnosis. As the cause of erroneous diagnosis, association between cancer and benign tumor was seen frequently in 24 cases, followed by follicular carcinoma without nuclear atypia in 7 cases. Among 123 cases in which cells were not sampled, cystic degeneration of cancer lesion itself was found in 7 cases (6 of them had papillary carcinoma). Even when cystic fluid was aspirated, cystic formation of papillary carcinoma should always be considered. Intranuclear cytoplasmic inclusion appeared in papillary carcinoma (117/140), follicular carcinoma (8/20), anaplastic carcinoma (1/8) and medullary carcinoma (1/3), but none in benign tumor. Among other cytological findings, multinucleated cell, nuclear atypia, coarse granular chromatin, papillary cell arrangement and hypercellularity frequently appeared in malignant tumor. The complications related to fine needle aspiration were not seen except for subcutaneous hemorrhage. Fine needle aspiration cytology made it possible to predict the histological type and proved to be useful in planning for the preoperative therapy.

Immunoelectron microscopic localization of thyroglobulin (TG) in the thyroid gland in Basedow's disease.

An electron microscopic immunohistochemical localization of thyroglobulin (TG) using PAP methods from Epok-812 embedded tissues has been made in human thyroids obtained from 15 patients with treated Basedow's disease aged 13 to 43 years. Follicular cells vary considerably in shape and content of cytoplasmic organelles depending mainly upon the size of follicles. Reaction product for TG coincided well with previous investigations studied by electron microscopic autoradiography and is strongly positive in most follicular lumina having no relation to their size, reabsorbed colloid droplets or small subapical vesicles. The reabsorbed colloid droplets are rarely observed in cells surrounding distended follicles and more frequently appeared in small follicles. The reabsorbed colloid droplets after fusion with lysosomes show a variable amount of reaction products from intense deposition to a complete absence of product indicating hydrolysis of TG by lysosomal enzymes. There is no reaction product in rough endoplasmic reticulum or Golgi apparatus in spite of positive reaction product in the subapical vesicles. These subapical vesicles are composed of both endocytotic and exocytotic vesicles.