Chronic lymphocytic thyroiditis (CLT) has a positive prognostic value in papillary thyroid cancer (PTC) patients: the potential key role of Foxp3+ T lymphocytes.

BACKGROUND: An impact of chronic lymphocytic thyroiditis (CLT) on papillary thyroid cancer (PTC) outcome has long been advocated but it is still controversial. PURPOSE: The aim of this study was to evaluate the prognostic value of CLT in a retrospective cohort of PTC patients and to characterize the lymphocytic subpopulations and infiltrate (LI). MATERIALS AND METHODS: We assessed 375 PTC patients, aged 45.2 ± 16.4 years, and treated with thyroidectomy and radioiodine remnant ablation, with a mean follow-up of 6.28 ± 3.86 years. In a subgroup of patients (n = 81) tissue sections were reviewed for the presence of CLT or lymphocytes associated with tumor in absence of background thyroiditis (TAL); cytotoxic CD8+/regulatory Foxp3+ T lymphocyte (CD8+/Foxp3+) ratio was characterized by immunohistochemistry: a low ratio is suggestive of a less effective anti tumor immune response. RESULTS: Seventy-five/375 patients (20%) had a histological diagnosis of CLT and showed at the last follow-up a significantly better outcome compared to those with no CLT (cure rate: 91.8 versus 76.3%, p = 0.003). LI was characterized in 81 PTC patients (24 with CLT and 57 with TAL): the peri-tumoral CD8+/Foxp3+ ratio was lower in patients not cured at the final evaluation. CONCLUSIONS: Our data suggest that concurrent CLT has a protective effect on PTC outcome and that the imbalance between cytotoxic and regulatory T lymphocytes in the peri-tumoral TAL may affect the tumor-specific immune response favoring a more aggressive behavior of cancer.

Ectopic thyroid of the lung. An additional case.

Thyroid ectopy is a rare phenomenon, which usually occurs in the cervical midline. We, herein, illustrate an unusual location of thyroid tissue, incidentally found at autopsy within the lung of a 77-year old male.

Scarring in papillary carcinoma of the thyroid: report of two new cases with exuberant nodular fasciitis-like stroma.

AIMS: To describe two new cases of papillary carcinoma of the thyroid with exuberant nodular fasciitis-like stroma, one of which was characterized by previously unreported transformation into a poorly differentiated lesion. Moreover, we explore the presence of TGF-beta to help to clarify the pathogenesis of the collagen formation. METHODS AND RESULTS: The case characterized by an aggressive behaviour exhibited areas of transformation into a poorly differentiated (insular) carcinoma of the thyroid. In both cases, as revealed by immunohistochemistry, neoplastic cells produced and secreted high amounts of TGF-beta. On the contrary, TGF-beta immunoreaction was never present in the normal thyroid or in papillary carcinomas without collagen bundles, while a weak, exclusively intracellular reaction was present in a patchy manner in cases showing intratumoral fibrous bundles. CONCLUSIONS: The rare variant of papillary thyroid carcinoma characterized by exuberant stroma may give rise to more aggressive lesions, as do other histotypes of differentiated thyroid carcinomas. TGF-beta, the fundamental cytokine which mediates scarring and activation of myofibroblasts, most probably induces the exuberant stroma.

Effects of testosterone on the liver of castrated rats: morphologic study.

It is well known that castration in rats causes atrophy of the sexual organs and, to a lesser extent, of other organs. We have observed that castration causes a reduction of the liver weight due to a reduction (-10%) of the numerical density of the hepatocytes after castration (p less than 0.01). Testosterone administration at high concentration (2.5 mg/100 g b. wt.) as well as at low concentration (0.025 mg/100 g) in the castrated rats causes an increase of the liver weight due to an increase (+30%) in the cellular area (p less than 0.001) as well as in the nuclear area (+20%) (p less than 0.01) of the hepatocytes, revealing a powerful hypertrophic effect of the hormone in the liver.