Follicular neoplasms

Fig. 2. Human thyroid biopsies. 1D >H MR spectra (8.5 T, 37°C) residual water suppressed by selective gated irradiation, sweep width 3957 Hz, using 8192 data points, 128 accumulations, and acquisition time of 1.14 s and relaxation delay of 2 s. (a) Normal thyroid tissue, (b) Known follicular carcinoma, (c) Thyroid follicular neoplasm predicted by MRS to be normal—confirmed by histopathology. (d) Thyroid follicular neoplasm predicted by MRS to be cancer and confirmed by histopathology—the presence of capsular invasion. Reprinted with permission from the National Research Council, Canada.

In a more recent series, Mase and colleagues demonstrated positivity in 13% of adenomatous goiters, 27% of adenomas, 84% of follicular carcinomas, and 97% of papillary carcinomas (Fig. 10.14). Among follicular neoplasms, the sensitivity for the detection of carcinomas was 84.6%, while specificity, positive predictive value, and overall accuracy were 72.6%, 66%, and 77.2%, respectively.Sack and colleagues have concluded that a positive result for HBME-1 on FNA is... 

Deletions and point mutations involving mitochondrial DNA are common in follicular neoplasms of oncocytic type, but the role of these mutations in the genesis of the tumors is unknown.Mutations of the GRIM-19 gene, which is involved in the mitochondrial respiratory chain and in apoptosis, have been found in 15% of oncocytic carcinomas but do not occur in other thyroid tumor types. 

Liberman E, Weidner N. Papillary and follicular neoplasms of the thyroid gland Differential immunohistochemical staining with high molecular weight keratin and involucrin. Appl Im-munohistochem. 2000 8 42-48. 

Mase T, Funahashi H, Koshikawa T, et al. HBME-1 immunostaining in thyroid tumors especially in follicular neoplasms. Endocr J. 2003 50 173-177. 

A rise in papillary carcinoma from most series is accompanied by a decrease in the incidence of follicular carcinoma, which was sometimes not as marked as in Salta (Tables 53.4 and 53.6), probably due to the use of routine systematic capsule sampling from follicular neoplasms from the 1980s leading to more frequent identification of minimally invasive follicular carcinomas (Harach et al, 2002 Harach and Williams, 1995 Lang et al, 1980). If this had occurred, the real change in the papillary to follicular carcinoma ratio would have been greater, but would not have affected the incidence of papillary carcinomas, as microcarcinomas were excluded. Furthermore, an increase... 

Osborne-Mendel rats were fed technical-grade heptachlor (73%) males received TWA doses of 1.94 and 3.9 mg/kg/day and females received TWA doses of 1.28 and 2.56 mg/kg/day for 80 weeks (NCI 1977). The results of this study showed a statistically significant increase in follicular cell neoplasms in the thyroid (adenomas and carcinomas) in females fed the high dose compared to controls. This finding was discounted by the investigators, however, because the incidence rates were low and are known to be variable in the control rat population. Rates of tumor incidences in males were not increased. 

At dosages above 30mg/kg in the diet, chlordane interfered with reproduction in rats and mice, but this effect was reversible after exposure ceased." Pre- and postnatal exposures to chlordane altered the development of the immune system in rodents. A dose-related increase in the incidence of hepatocellular carcinomas was found in male and female mice fed approximately 60mg/k chlordane for 80 weeks. In rats, increases in the incidences of thyroid follicular cell neoplasms were observed. ... 

A recent study confirmed that ethylene thiourea was carcinogenic in male and female rats as shown by increased incidences of thyroid follicular cell neoplasms after treatment of up to 250 ppm in the diet for 2 years. In mice, concentrations ranging from 100 to 1000 ppm for 2 years caused liver and pituitary tumors in addition to thyroid tumors. Perinatal exposure up to 8 weeks followed by a control diet for 2 years was not carcinogenic in rats or mice. Combined perinatal-adult ETU exposures produced the same carcinogenic effects as adult-only exposures. 

Chronic oral exposure of rats and mice to MDA and its dihydrochloride is carcinogenic. Treatment-related increases in the incidences of thyroid follicular cell adenomas and hepatocellular neoplasms were observed in mice after chronic ingestion of MDA in drinking water. In rats, increases in the incidences of thyroid follicular cell carcinoma and hepatic nodules were observed in males and thyroid follicular cell ademonas occurred in females. Although not statistically significant, certain uncommon tumors such as bile duct adenomas, papillomas of the urinary bladder, and granulosa cell tumors of the ovary also were reported. These tumors are of low incidence in historical controls. In another report, MDA acted as a promoter of thyroid tumors in rats. °... 

A major breakthrough in the treatment of lymphoid malignancies was the discovery of monoclonal antibody activity, especially that of rituximab. Rituximab was the first monoclonal antibody approved by the U.S., FDA for the treatment of relapsed follicular lymphoma (1), and it has now been extensively used for the treatment of various lymphoid neoplasm which express CD20 antigen. Its efficacy has been also demonstrated against diffuse large B-cell lymphoma when administered as a combination regimen such as rituximab plus CHOP (R-CHOP) chemotherapy (2). 

Follicular lymphoma (FL) is the most extensively investigated subtype of lymphoid neoplasm regarding the influence of FeyRs polymorphism on treatment Depending on the clinical situation and patients circumstances, there are various options for the treatment for FL. In this chapter, we summarize the impact of FcyR gene pol5miorphisms not... 

Interferons are proteins or glycoproteins that are produced either by animal cells or plant cells in response to stimuli or DNA recombinant technology. These drugs are active against malignant neoplasms and have immunomodulating effects. These are useful in chronic hepatitis B, hepatitis C, hairy cell leukemia, myeloid leukemia, follicular lymphoma, carcinoid tumor, multiple myeloma, renal cell carcinoma, multiple sclerosis, chronic granulomatous diseases, blood disorders, common cold, herpes simplex, inflammatory bowel disease, and leishmaniasis. 

CD21 is a useful marker to identify neoplasms of follicular dendritic cells. The antigen density on dendritic reticulum cells is fairly high however, the same antigen is expressed at low levels on mantle zone B cells, which makes an excellent low-level control. 

Thyroid follicular cell adenomas were increased in female mice treated with TBA, but this result lacks any independent supporting evidence from a number of studies in mice and rats. There was no evidence for a hepatic effect of TBA within this mouse carcinogenicity study therefore, no internal evidence exists for a hormonal mechanism of thyroid follicular cell induction. No thyroid neoplasms were increased in the carcinogenicity studies of MTBE. 

---