Changes in the Demographic and Clinicopathological Characteristics of Thyroid Cancer: A Population-Based Investigation in Algeria, 1993-2013

Diagnostic utility of anti-thyroid peroxidase immunohistochemistry in the identification of papillary thyroid carcinoma

The routine histomorphological assessment of follicular thyroid neoplasms has been subject to interobserver or intraobserver variability among histopathologists. Anti-thyroid peroxidase (anti-TPO) has emerged as a useful immunohistochemical (IHC) marker, with its expression lost in papillary thyroid carcinoma (PTC). Our study aims to determine the diagnostic accuracy of anti-TPO IHC expression in the identifying PTC and its variants, particularly the Follicular variant of papillary thyroid carcinoma (FVPTC), with H&E assessment as the gold standard. Anti-TPO IHC (DAKO-MoAb47) was performed on 110 cases, including 76 malignant tumors (classic PTC, FVPTC, follicular carcinoma (FC), and oncocytic carcinoma (OC)) and 34 benign tumors (non-invasive follicular tumor with papillary-like nuclear features (NIFTP) and follicular adenoma (FA)). The loss of expression in more than or equal to 51 % of thyrocytes was considered suggestive of a PTC profile. The sensitivity of the loss of anti-TPO expression for identifying PTC among all carcinomas was 61.7 %, specificity was 75 %, positive predictive value was 90.2 %, negative predictive value was 34.2 %, and accuracy was 64.4 %. The loss of anti-TPO IHC expression combined with routine H&E assessment, supports the identification of PTC and its variants.

Epidemiological and histopathological characteristics of thyroid carcinoma in a Tunisian health care center

Background

Thyroid carcinoma (TC) accounts for almost 0.5%-1% of total malignancies. Its incidence is increasing rapidly worldwide. Several studies have drawn up the epidemiological profile of TC and its clinical and pathological features. However, to date, no similar studies have been conducted in Tunisia.

Aims

To establish an epidemiological profile of TC in a Tunisian health care institute and to analyze its clinical and histopathological characteristics in our institute.

Materials and Methods

We present a retrospective study reviewing the cases of TC diagnosed in our institution in a 4-year period.

Results

We collected a sample of 192 cases of TC. It consisted of 31 males and 161 females (83.8%) with a sex-ratio M/F of 0.19. The mean age was 46.4 years. Papillary thyroid carcinoma was the most frequent histological subtype. The multifocality rate was 33.8%. The mean size of TC was 2.2 ± 1.9 cm. 60.9% of TC were staged pT1 and 20.3% had nodal involvement. Papillary thyroid microcarcinomas were noted in 37.5% of cases.

Conclusion

Our results were consistent with those of the literature. A high proportion of pT1 and pN0 tumors were noted in our series, suggesting that TC's diagnosis and management was performed at an early stage of the disease in our institution. In addition, our study enabled us to notice the impact of the Coronavirus disease 19 crisis on the management of TC in our institution. Further studies are needed to establish the epidemiological profile of TC in Tunisia and to assess its clinical and pathological features.

Thyroid cancer incidence and trends by demographic and tumor characteristics in Oran, Algeria: 1993-2013, a population-based analysis

OBJECTIVES

Incidence rates of thyroid cancer have dramatically increased over recent decades in many countries, particularly the papillary histotype and microcarcinomas. We examined thyroid cancer incidence and trends by demographic and tumor characteristics based on 1443 patients with thyroid cancer diagnosed between 1993 and 2013 in Oran district, in Northwest Algeria.

METHODS

All thyroid cancer cases were abstracted from medical records and pathology reports and classified according to the International Classification for Diseases in Oncology, third edition. Age-specific, age-standardized incidence rates per 100 000 person-years, and annual percent changes (APC) in the incidence were calculated.

RESULTS

Age-standardized incidence was 11.7 per 100 000 for women and 2.0 per 100 000 for men. Thyroid cancer incidence increased over time significantly in women (APC: +3.72%; P < 0.05), mostly due to an increased incidence of the papillary histotype (APC: +5.48%; P < 0.05), and microcarcinomas (APC: +17.34%; P < 0.05). During the same time period, the incidence of follicular thyroid carcinomas decreased (APC: -3.74%; P < 0.05).

CONCLUSIONS

The results of our study showing an upward trend of thyroid cancer incidence driven largely by increases in the papillary histotype are consistent with previous studies. The higher increase has coincided with the introduction of fine needle aspiration and thyroid ultrasound in the 1990s, and may have led to overdiagnosis. However, the increased papillary-to-follicular ratio observed over time is possibly a late effect of iodine supplementation implemented in Algeria in 1967 to combat endemic goiter. Further larger-scale population-based research is needed to gain insight into thyroid cancer etiology.

Hormonal Replacement Therapy and Risk of Thyroid Cancer in Women: A Meta-Epidemiological Analysis of Prospective Cohort Studies

Objectives

Many experimental studies have reported that female sex hormones involve thyroid cancer development because the incidence rate of thyroid cancer in women (TCW) is 3 times higher than in men. Three previous systematic reviews reporting no association between hormone replacement therapy (HRT) and TCW risk had the same search year of 2014. The aim was to reevaluate the association between HRT use and TCW risk using a meta-epidemiological study of prospective cohort studies.

Methods

The study preferentially used all studies selected by the existing systematic reviews and then secured an additional cohort from the list citing the studies. The selection criterion was defined as the prospective cohort study assessing the association between HRT and TCW risk by adjusted relative risk and its 95% confidence intervals (CI) from multivariate analysis. A random-effects model meta-analysis was applied to estimate summary relative risk (sRR) and its 95% CI. A publication bias was evaluated by Egger’s test; moreover, the statistical significance level was set at 5%.

Results

Nine cohort studies were finally selected. The random-effect model was applied because of heterogeneity (I² = 64.3%). The sRR and its 95% CI from a random-effects model meta-analysis had no statistical significance in the association between HRT and TCW risk (sRR = 1.11; 95% CI, 0.98–1.26). Additionally, Egger’s test revealed no statistical significance (P = 0.91).

Conclusions

HRT is not associated with TCW risk based on the random-effects model meta-analysis of prospective cohort studies published until now.