A clinicopathologic study of 241 cases of papillary thyroid carcinoma treated at the University of Florence Medical School, Florence, Italy is presented. The features of greatest prognostic value were patient's age at presentation, small tumor size, total encapsulation, extrathyroid extension, multicentricity, and presence of distant metastases. The prognosis of the disease was not influenced by the pattern of tumor growth, presence of solid areas, initial presence or subsequent development of cervical lymph node metastases, type of initial thyroid operation, performance of neck dissection, or prophylactic administration of radioactive iodine. It is concluded that conservative thyroid surgery in the form of lobectomy, without neck dissection or prophylactic administration of iodine 131 (131I), constitutes adequate therapy for most cases of papillary thyroid carcinoma. More extensive therapy should be considered for older patients and for those in whom the tumor exhibits extrathyroid extension or easily detectable multicentricity.

The lats gene has been identified as a tumour suppressor in Drosophila melanogaster using mosaic screens. Mosaic flies carrying somatic cells that are mutant for lats develop large tumours in many organs. The human LATS1 homologue rescues embryonic lethality and inhibits tumour growth in lats mutant flies, demonstrating the functional conservation of this gene. Biochemical and genetic analyses have revealed that LATS1 functions as a negative regulator of CDC2 (ref. 3). These data suggest that mammalian LATS1 may have a role in tumorigenesis. To elucidate the function of mammalian LATS1, we have generated Lats1-/- mice. Lats1-/- animals exhibit a lack of mammary gland development, infertility and growth retardation. Accompanying these defects are hyperplastic changes in the pituitary and decreased serum hormone levels. The reproductive hormone defects of Lats1-/- mice are reminiscent of isolated LH-hypogonadotropic hypogonadism and corpus luteum insufficiency in humans. Furthermore, Lats1-/- mice develop soft-tissue sarcomas and ovarian stromal cell tumours and are highly sensitive to carcinogenic treatments. Our data demonstrate a role for Lats1 in mammalian tumorigenesis and specific endocrine dysfunction.

The data identify FOXP3 expression as a new independent prognostic factor in breast carcinoma, which might help to improve the selection of patients for appropriate therapy.

Seventy cases of anaplastic thyroid carcinomas studied at the Universities of Florence (Italy) and Minnesota are presented. Three morphologic patterns were seen: spindle, giant cell, and squamoid, sometimes in combination. Ultrastructurally, evidence of epithelial differentiation was seen in most but not all cases studied. Immunohistochemically, a stain for cytokeratin using a monoclonal antibody was found the most useful adjunct to diagnosis. Unexpected positivity for carcinoembryonic antigen (CEA) was found in several squamoid tumors. The alleged frequent positivity of this tumor type for thyroglobulin and calcitonin was not confirmed. A third of the tumors were associated with a better differentiated component, of which, presumably, they represented a dedifferentiation. The extremely aggressive behavior of anaplastic thyroid carcinomas was confirmed amply in this series: all of the patients in whom follow-up information was available died of their tumor. Small cell tumors should not be included into the anaplastic category, since they invariably belong to other groups, i.e., malignant lymphoma, medullary carcinoma, and poorly differentiated ("insular") carcinoma.