Initial treatment of differentiated thyroid carcinoma

PRR15 Is a Novel Diagnostic and Prognostic Biomarker in Papillary Thyroid Cancer and Modulates the Tumor Microenvironment

Papillary thyroid cancer (PTC), accounting for more than 80 percent of all cases of thyroid cancer, is a form of a cancerous tumor that has a very favorable prognosis. However, patients diagnosed with PTC who are already in an advanced state have a dismal outlook. This study aimed to establish the diagnostic relevance of PRR15 expression in PTC patients as well as its levels in PTC samples and its connection with immune infiltrates. The TCGA and GEO datasets were combed through to obtain information on PTC patients. The “Limma” program was used to screen for differentially expressed mRNAs (DEMs), and the results were displayed using volcano plots and heat maps. The Wilcoxon test was used to examine the level of PRR15 expression in PTC patients in comparison with that of normal tissues. To study the connection between the immune infiltration level and PRR15 expression in PTC, the single-sample sequence set enrichment analysis (ssGSEA) from the R package was utilized. The expression of PRR15 was analyzed with RT-PCR in PTC cells and normal cells. In order to evaluate the diagnostic significance of PRR15 expression, ROC assays were carried out. Experiments using CCK-8 were carried out to investigate the impact that PRR15 knockdown could have on the proliferation of PTC cells. In this study, 17 overlapped DEMs between PTC specimens and normal specimens were identified, including MPPED2, IPCEF1, SLC4A4, PKHD1L1, DIO1, CRABP1, TPO, TFF3, SPX, TCEAL2, ZCCHC12, SYTL5, PRR15, CHI3L1, SERPINA1, GABRB2, and CITED1. Our attention focused on PRR15 which was highly expressed in PTC specimens as compared with nontumor specimens. PRR15 had an AUC value of 0.926 (95% CI 0.902–0.950) for PTC based on TCGA datasets. Pan-cancer assays suggested PRR15 as an oncogenic gene in many types of tumors. Moreover, we found that PRR15 expression was positively correlated with eosinophils, NK cells, NK CD56bright cells, IDC, macrophages, DC, mast cells, and Th1 cells. Further investigations with CCK-8 demonstrated that inhibiting PRR15 resulted in a decrease in the proliferation of PTC cells. Overall, PRR15 was confirmed to be a biomarker for PTC patients and a predictor of response to immunotherapy.

Stimulated Serum Thyroglobulin Levels versus Unstimulated Serum Thyroglobulin in the Follow-up of Patients with Papillary Thyroid Carcinoma

Serum thyroglobulin (Tg) and thyroid whole-body radioiodine scintigraphy (TWBS) are used in the follow-up of patients with papillary thyroid carcinoma (PTC) after total thyroidectomy. Symptoms of hypothyroidism are frequent as patients discontinue levothyroxine 1 month before visit, favoring the use of unstimulated serum Tg (uSTg) only. This study was done to determine the reliability of stimulated serum Tg levels (sSTg) over uSTg. A total of 650 patients with PTC came for follow-up between June 2011 and 2016. In those who had levels of uSTg and sSTg months measured within an interval of median of 3 months (range from 1 to 8 months), risk stratification was done as per the American Thyroid Association guidelines 2015. Intervention was based on a cutoff value of sSTg >10 ng/ml in our institution and the same was used for data analysis. Out of 650 patients, 106 had paired Tg values. Low-, intermediate-, and high-risk groups comprised 40, 31, and 35 patients, respectively. The sSTg >10 ng/ml with uSTg <10 ng/ml in the same patient was noted in 22.5% (9/40) of the low-risk, 41.9% (13/31) of the intermediate-risk, and 14.2% (5/35) of the high-risk groups. The levels were corroborated with tumor burden as determined by additional clinical, ultrasonography neck, and TWBS findings. Our study highlights the superiority of sSTg over uSTg in the follow-up of PTC patients. Follow-up with uSTg alone may result in underestimating the tumor burden.

Diagnostic and therapeutic use of recombinant human TSH (rhTSH) in differentiated thyroid cancer

Traditionally, withdrawal of thyroid hormone to increase serum levels of thyroid-stimulating hormone (TSH) has been used in patients with differentiated thyroid carcinoma (DTC) to optimize radio-iodine uptake and serum thyroglobulin (Tg) stimulation during follow-up and in preparation for radio-iodine therapy. However, this procedure is associated with signs and symptoms of hypothyroidism which negatively affect the patient's quality of life. Recombinant human thyrotropin (rhTSH) has provided an effective alternative to thyroid hormone withdrawal. After favourable experimental trials in humans, rhTSH obtained regulatory approval in North America and in Europe as a diagnostic tool, and more recently as a preparation for radio-iodine thyroid remnant ablation. Since then, rhTSH has radically changed the diagnostic and therapeutic management of DTC patients. This review will focus on the clinical application of rhTSH in the management of DTC, highlighting current indications and future perspectives.

Altered expression of cyclins and cell cycle inhibitors in papillary thyroid cancer: prognostic implications

Currently we lack biochemical or molecular markers that predict recurrence and metastases in thyroid cancer. Recent studies in a number of other human malignancies indicate that expression and/or subcellular localization of certain cell cycle regulators has prognostic utility. We have investigated the expression of cyclins D1 and E and of cyclin-dependent kinase inhibitor's p21 and p27 in papillary thyroid cancer (PTC) and correlated this with clinical/histological stage at diagnosis and with clinical outcome. PTCs were compared to normal thyroid, adenomas, and undifferentiated thyroid cancers (UTCs). Our studies indicate that PTCs and UTCs demonstrate low nuclear expression of cyclin E and p27, allowing a clear distinction between adenomas and these carcinomas (p < 0.004). A pattern of low nuclear expression of all four markers was observed in stage IV PTCs and UTCs, while stage I PTCs had low D1 and E accompanied by high p21 or p27. Expression of cytoplasmic cyclin D1 was significantly lower in stage IV PTCs and UTCs than in stage I-III PTC's (p </= 0.020), and appeared to correlate inversely with poor outcome in PTCs (p = 0.010). These studies suggest that evaluation of a panel of these markers and attention to their subcellular localization may be a useful adjunct in differentiating benign from malignant thyroid neoplasms and in predicting tumor behavior.

Overview of the management of differentiated thyroid cancer

Thyroid cancer is an uncommon tumor accounting for roughly 1% of all new malignancies. Differentiated (ie, papillary or follicular) thyroid carcinoma is usually asymptomatic, and frequently appears as a solitary thyroid nodule but few show cervical lymphadenopathy or metastasis to lung, bone, or liver. Fine needle aspiration (FNA) is recommended in the initial diagnostic test. Depending on the size of the lesion and other associated risk factors, most patients are treated with total or near total thyroidectomy. Postoperative radioiodine ablation is performed when tumor has a potential for recurrence. Recurrence rates and cancer-specific mortality is decreased by suppressing thyroid stimulating hormone (TSH). Long-term surveillance and follow-up with physical examination every 3 to 6 months for 2 years and then annually if patient remains cancer free. Whole body iodine scans are done every 12 months for follow-up until one negative scan (either withdrawal of thyroid hormone or rhodium complex -TSH). Thyroglobulin measurements (with antithyroglobulin antibodies) and ultrasound neck are suggested at 6 and 12 months and then annually if disease free.

Papillary thyroid cancer with an initial presentation of abdominal and flank pain

PURPOSE

Well-differentiated thyroid cancer typically presents as a thyroid mass. Common sites of metastases upon presentation include cervical lymph nodes, lung, and bone. Well-differentiated thyroid cancer with clinically apparent kidney metastases is rare, with fewer than 20 cases reported in the literature. In the vast majority of these cases, the patients had known thyroid neoplasms at the time the renal metastases were identified. We report a case of papillary thyroid carcinoma that presented with abdominal pain in a 25-year-old woman with no previous history of thyroid disease.

STUDY DESIGN

This study is a case report.

RESULTS

The patient underwent radical nephrectomy for a right renal mass, which was diagnosed as papillary thyroid carcinoma follicular variant. During subsequent evaluation, metastatic disease was also identified in the patient's lungs. The patient was treated with total thyroidectomy and iodine 131.

CONCLUSIONS

Papillary cancer, which ordinarily behaves in an indolent manner, can have unusual presentation, including disseminated metastasis on presentation. Renal metastases are extremely rare.

Incidental discovery of pulmonary metastases during I-131 scintigraphy after total thyroidectomy

We report the case of a 40-year-old man with radiographically silent pulmonary metastases of papillary thyroid cancer discovered during I-131 scintigraphy following total thyroidectomy performed 10 years after unilateral lobectomy. The residual lobe was histologically normal. After a dose of 11.1 GBq (300 mCi), there was no I-131 uptake in the thyroid bed and lung metastases, and serum thyroglobulin became undetectable. Conservative therapy could be associated with a delay in the possibility of diagnosing and treating extrathyroidal metastases.

Role of metastasectomy in the management of thyroid carcinoma: the NIH experience

BACKGROUND AND OBJECTIVES

We studied the impact of metatasectomy on disease outcome in 29 advanced nonmedullary thyroid carcinoma (ThyrCa) patients who were operated on between 1969 and 2001 at NIH to further define its role in the management of this malignancy.

METHODS

Data were extracted by retrospective chart review. A Kaplan-Meyer survival curve was constructed, and comparative stratification for various parameters was performed.

RESULTS

During 47 surgeries, the following lesions were resected from mid-mediastinum/hila, 17; lung parenchyma, 12; skeleton, 14; kidneys, 2; and brain, 2. All patients received multiple radioiodine (RAI) treatments. External-beam radiotherapy, chemotherapy and other palliative measures were used in selected patients. Six patients (21%) died within 74.7 +/- 54.7 months after the first distant metastasectomy. The outcome of the remaining patients was as follows: complete remission, 3; partial remission, 10; and 10: progressive disease, 10, with a follow-up of 175 patient-years. Metastasectomy led to a decrease of 38% in thyroglobulin levels in 23 patients. Cumulative survival rates were 78.5 +/- 8.4% at 5 years and 50.2 +/- 12.5% at 10 years (mean +/-SEM) after initial distant metastasectomy.

CONCLUSIONS

Our data show that extensive targeted metastasectomy in the setting of a tertiary center can be beneficial to patients with disseminated ThyrCa with persistent or recurrent distant disease, when used in conjunction with nonsurgical treatment modalities.

Adenovirus biodistribution and noninvasive imaging of gene expression in vivo by positron emission tomography using human sodium/iodide symporter as reporter gene

Amongst the various methods that can be developed for noninvasive monitoring of gene expression in vivo, the use of positron emission tomography (PET) appears to be the most promising both for preclinical and clinical studies. Various genes have been described as potential PET reporters, but there is a need to develop new approaches that exploit transgenes with both therapeutic and imaging potential. The Na/I symporter (NIS) gene is expressed mainly in the thyroid and is responsible for iodide accumulation in this organ. The NIS gene has been used in gene therapy experimentation. Ectopic expression of this gene in various type of malignant cells has led to radiosensitization and in some cases tumor regression in xenograft models in nude mice, highlighting the therapeutic potential of this approach. In the present study, we demonstrate the potential of the human NIS gene (hNIS) as a reporter gene. Expression of hNIS, after plasmid transfection or adenoviral gene delivery, can be monitored in vitro on incubation with (125)I. Iodide uptake in the transduced cells can be directly correlated with the levels of gene expression in vitro. Ectopic expression of the NIS gene in vivo can be monitored in biodistribution studies on intravenous injection of (125)I. Adenovirus delivery induces gene expression essentially in the liver, adrenal glands, lungs, pancreas, and spleen. Expression of hNIS in tumor xenograft models can also be detected when the virus is injected intratumorally. Finally, hNIS expression was monitored by PET after intravenous injection of (124)I, demonstrating the potential of this approach for noninvasive imaging.