Differentiated thyroid cancer: a retrospective analysis of 832 cases from Greece

No considerable changes in papillary thyroid microcarcinoma characteristics over a 30-year time period

Background

The prevalence of papillary thyroid microcarcinoma (PTMC) is continuously increasing but its clinical significance and management is still debatable. The aim of this study was to investigate possible changes in the clinical presentation, tumor characteristics, treatment modalities and long-term outcome during the last three decades in patients with PTMC.

Methods

We studied 335 patients with PTMC who were followed up for at least 5 years, from 1982 to 2015, and treated in accordance with the current literature or guidelines at each time-period. Patients were classified according to year of diagnosis into two time periods, TP1 from 1982–2000 and TP2 from 2001–2010.

Results

The mean follow-up of the whole cohort was 10.6 ± 5.3 (median 9) years. No change was noted in the mean age at diagnosis or the female to male ratio during the two time periods. In regard to tumor characteristics, multifocality and non-encapsulated follicular variant of PTMC was more often present while classic PTMC was less common in patients in the TP2, compared to patients in the TP1 (p = 0.007, p < 0.001 and p = 0.043 respectively). The prevalence of incidental PTMC was high but similar in both time periods (84.6 vs 80 %, p = 0.286). The majority of patients in TP2 underwent a total or near total thyroidectomy compared to patients in TP1 (91.7 vs 80 %, p = 0.001). However, more patients underwent thyroidectomy for toxic multinodular disease and less for Graves’ disease during TP1 compared to patients in the TP2 (p = 0.02 and 0.043 respectively). A significant percentage of patients underwent adjuvant radioiodine ablation, yet no difference was found between the two time periods (73.8 vs 79.5 %, p = 0.228). The rate of persistence was very low and not significant (3.1 vs 6.6 %, p = 0.165), while disease recurrence was observed in only 2 (0.6 %) patients, one from each time period.

Conclusions

We did not observe any important changes regarding the clinical presentation or tumor characteristics of PTMCs during a 30-year period. With applied interventions a favorable course was confirmed in the majority of patients without differences in recurrence or persistence during the last three decades.

Changes in TNM stage, reoperation and 131-I ablation rate during the use of newer methods for the preoperative diagnosis of differentiated thyroid carcinoma

OBJECTIVE

To define and discuss the changes of important risk factors and TNM staging over the last 40 years in patients operated on for differentiated thyroid carcinoma (DTC), resulting from the introduction of newer sensitive diagnostic procedures in the preoperative evaluation of thyroid nodules.

PATIENTS

We reviewed the medical records of 1251 patients with postoperative diagnosis of DTC who had undergone initial diagnosis, before surgery, at our unit, between 1971 and 2010. According to the period of diagnosis, the patients were divided into four groups (I, II, III, IV) corresponding to the four decades.

RESULTS

The mean age at diagnosis was unchanged over time for both papillary (PTC) and follicular thyroid cancer (FTC). A decrease in the proportion of FTC (group I vs group IV P < 0·01) and a concomitant increase in PTC/FTC ratio was observed particularly in group IV. The significant decrease in the proportion of tumour size of PTC (group I vs group IV, P < 0·01), the increase in the proportion of microcarcinomas, from 22·4% in group I to 53·0% in group IV, P < 0·001, and the decrease in the number of cases with features of aggressiveness have changed the TNM stage towards stages I and II. The overall frequency of patients at high risk was significantly decreased, from 8·0% in group I to 1·8% in group IV. The number of patients who underwent reoperation for the completion of tumour resection and/or radioiodine therapy significantly decreased over time.

CONCLUSIONS

The evaluation of thyroid nodules using the newer diagnostic methods was useful in identifying DTC early. Consequently, the reoperation and thyroid remnant ablation rates were reduced.

Follicular adenoma and carcinoma of the thyroid gland

Follicular neoplasms of the thyroid gland include benign follicular adenoma and follicular carcinoma. Currently, a follicular carcinoma cannot be distinguished from a follicular adenoma based on cytologic, sonographic, or clinical features alone. The pathogenesis of follicular carcinoma may be related to iodine deficiency and various oncogene and/or microRNA activation. Advances in molecular testing for genetic mutations may soon allow for preoperative differentiation of follicular carcinoma from follicular adenoma. Until then, a patient with a follicular neoplasm should undergo a diagnostic thyroid lobectomy and isthmusectomy, which is definitive treatment for a benign follicular adenoma or a minimally invasive follicular cancer. Additional therapy is necessary for invasive follicular carcinoma including completion thyroidectomy, postoperative radioactive iodine ablation, whole body scanning, and thyrotropin suppressive doses of thyroid hormone. Less than 10% of patients with follicular carcinoma will have lymph node metastases, and a compartment-oriented neck dissection is reserved for patients with macroscopic disease. Regular follow-up includes history and physical examination, cervical ultrasound and serum TSH, and thyroglobulin and antithyroglobulin antibody levels. Other imaging studies are reserved for patients with an elevated serum thyroglobulin level and a negative cervical ultrasound. Systemic metastases most commonly involve the lung and bone and less commonly the brain, liver, and skin. Microscopic metastases are treated with high doses of radioactive iodine. Isolated macroscopic metastases can be resected with an improvement in survival. The overall ten-year survival for patients with minimally invasive follicular carcinoma is 98% compared with 80% in patients with invasive follicular carcinoma.

Prognostic value of lymph node metastases of differentiated thyroid cancer (DTC) according to the local advancement and range of surgical excision

In differentiated thyroid carcinoma (DTC) with primary tumor smaller than 1 cm, the routine central lymph node (LN) dissection is questioned, due to increased risk of post-surgery complications and lack of confirmed benefit.

Aim

The analysis of prognostic significance of LN metastases, in DTC patients to verify the potential role of central neck lymphadenectomy on disease staging.

Materials and methods

The group of 195 DTC patients, primarily operated between 2004 and 2005, was retrospectively analyzed. 184 patients after radical operation, with no distant metastases diagnosed before surgery, were included into analysis. LN metastases were observed in 55 of cases (28%). In 124 cases only dissection of central LN compartment was performed, in 36 patients also uni- or bilateral modified cervical lymphadectomy was carried out. In 24 patients with tumor limited to the thyroid gland without suspicious lymph nodes, the routine central lymph node dissection was not done.

Results

Median follow-up was 4 years. The 5-year overall and disease free survival standardized ratio were 100% and 95% respectively. The risk of LN metastases increased with the more locally advanced cancer. In the group of 124 patients, in whom only central LN dissection was performed, LN metastases were diagnosed in 15 cases (12%). No significant relation between multifocality and frequency of central and/or lateral LN metastases was noticed. Significant correlation between N feature and extrathyroidal invasion was observed (p = 0,0003). The presence of LN metastases was related to worsening of disease free survival from 99 to 90%. During the follow-up recurrence occurred in 6 (3%) cases. In 24 patients in whom only total thyroidectomy was done, no local or distant recurrence was observed. The assessment of early postoperative complications (hypoparathyroidism, paresis of vocal cords) indicated that the frequency of early calcium balance disturbances was significantly lower in patients in whom central LN dissection was not performed (p = 0,04)

Conclusions

Our result indicate that in the early diagnosis of thyroid cancer, the occurrence of LN DTC metastases is rarer and was observed only in 12% of elective dissections of central LN node compartment, if no lateral dissection was indicated due to the lack of clinical suspicion. In DTC patients with tumor diameter <1 cm and no sonographical or inraoperative suspicion on LN involvement, routine central lymphadenectomy may be not obligatory.

Increasing prevalence of papillary thyroid carcinoma in recent years in Greece: the majority are incidental

BACKGROUND

New cases of well-differentiated thyroid cancer (DTC) are diagnosed more frequently worldwide. We investigated trends and differences in clinical and histological characteristics of new DTC cases presenting in one large center.

METHODS

During the last 34 years 852 follicular cell-derived DTC cases (83% papillary [PTC], 17% follicular [FTC] carcinoma) presented in the Endocrine Unit of the Department of Clinical Therapeutics in Alexandra Hospital (18.8% men, mean age 42.4 +/- 14.5 years). Patients were classified in three period groups according to year of diagnosis: period 1, 1963-1982; period 2, 1983-1992; and period 3, 1993-2007. We recorded the histological type, age at diagnosis, and, in period 3, the type of pre-existing thyroid disease, the stage, and tumor size.

RESULTS

During periods 1, 2, and 3, the mean age at diagnosis was 37.7 +/- 12.3, 42.4 +/- 14.53, and 44.1 +/- 14.9 years (p = 0.001), respectively, and the male to female ratio was similar. The prevalence of FTC was 22.7%, 28.1%, and 6.5%, respectively. In period 3, 51.6% of the PTCs were microcarcinomas (microPTC) <or=10 mm; these patients tended to be older (p = 0.09). Microcarcinomas were more frequent among patients operated for pre-existing multinodular goiter (MNG) or prominent hot nodule compared to pre-existing single cold nodule (p < 0.001, Pearson chi(2)). In period 3, 88% of the microPTC diagnoses were incidental. Of the incidental microPTCs detected in MNG, 25% had capsular invasion, 4.5% had lymph node involvement, and 3.6% had soft tissue involvement.

CONCLUSIONS

We hypothesize that the prevalence of FTC during the last decade in our center in Greece was very low due to correction of iodine deficiency and a relative increase in the prevalence of microPTC. More than 50% of PTC diagnosed during the last decade were microPTCs that were detected incidentally in older persons with preexisting MNG or a prominent hot nodule. This is one of the highest, if not the highest percentage of microPTCs that were incidentally detected. Despite many of these having features of invasiveness, most appear to remain clinically silent. Research is needed to identify factors predisposing microPTCs to evolve from a subclinical to a clinically apparent form.

Thyroid follicular adenoma producing parathyroid hormone-related protein with a normal serum calcium level

A 64-year-old woman had normal serum calcium and plasma parathyroid hormone levels, despite an extremely high plasma parathyroid hormone-related protein (PTHrP) level. She underwent medical screening at our hospital and several neck tumors were detected by ultrasonography. After surgical resection of these tumors, her plasma PTHrP level was normalized. Histological examination showed that the resected tumors were thyroid follicular adenomas, while immunohistochemistry revealed positive staining with a monoclonal antibody for PTHrP. This is a rare case of thyroid follicular adenoma producing PTHrP in a patient with a normal serum calcium level despite elevation of plasma PTHrP.

Subclassification of non-solid-type papillary thyroid carcinoma identification of high-risk group in common type

Two hundred and sixty-three cases of primary human papillary thyroid carcinoma (PTC) were analyzed. All cases met the following parameters: tumor size > or = 10 mm, no distant metastasis at presentation, and no coexistence of other histological type. The histological features of the solid/trabecular component, encapsulation, tall/columnar cell component and loss of polarity/cohesiveness were utilized to subclassify the 263 cases of PTC into five groups: solid type (15.6%), encapsulated group (9.5%), tall/columnar cell group (7.2%), micropapillary/discohesive group (19.8%) and not-otherwise-specified group (47.9%). We focused on the latter four non-solid groups and compared their prognosis with the solid type. The tall/columnar cell group showed the worst disease-free survival rate (DFS) analyzed by the Kaplan-Meier method, followed by the micropapillary/discohesive group. The not-otherwise-specified group and encapsulated group showed a better DFS rate than the solid type. Cancer-related death was noted in the tall/columnar cell group (21.1%) and micropapillary/discohesive group (3.8%), but not in the other groups. The four non-solid histological groups were further categorized into two prognostic groups: high-risk group (including tall/columnar cell group and micropapillary/discohesive group); and low-risk group (including encapsulated group and not-otherwise-specified group). Their 10-year disease-free survival rates were 78.7% and 93.1%, respectively. In the present study, histological grouping was significantly correlated with prognosis in the multivariate analysis according to the Cox proportional hazards regression model in addition to clinical parameters of extrathyroid invasion and gross lymph node metastasis, which predicts the patient outcome in terms of tumor recurrence and cancer-related death more precisely.

High rate of persistent/recurrent disease among patients with differentiated thyroid cancer in Saudi Arabia: factors affecting nonremission

BACKGROUND AND OBJECTIVES

A fairly high number of patients with differentiated thyroid cancer (DTC) in our center had locally advanced disease at presentation and/or persistent disease after standard treatment. Therefore, we conducted a retrospective study to find the rate of successful ablation and remission and the factors affecting these outcomes.

METHODS

The study included 100 consecutively treated patients (20 males, 80 females; median age 36 years) diagnosed with DTC. Univariate and multivariate logistic regression was used to evaluate the effect of risk factors on the persistence or recurrence of thyroid cancer. All patients underwent total thyroidectomy and had cervical lymph node dissection when indicated. All patients received sodium iodide I 131 ablation once or twice post surgery. Patients were followed clinically by neck ultrasound, (123)I whole body scan and by thyroglobulin measurements and other diagnostic tests as needed.

RESULTS

Over a median follow-up of 7.6 years (range 7-10 years), ablation occurred in 93%, remission in 50%, disease persisted without remission in 41%, and 9% had recurrence after at least 1 year of remission. Papillary thyroid cancer was found in 76%, the follicular variant in 14%, other variants (tall cell and sclerosing types) in 2%, Hurthle cell carcinoma in 4%, and pure follicular thyroid cancer in 4%. Compared with patients in remission, patients with persistent/recurrent disease were older (mean 41 versus 31 years, P=.003), had higher postoperative thyroglobulin (193 versus 29 ng/mL, P=.04) and more advanced TNM staging (P=.005). Risk factors significant for non-remission were age >40 years (odds ratio 4.1, 95% CI 1.5-10.9 years, P=.003) and TNM stage other than 1 (odds ratio 5.5, 95% CI 1.9-16.3, P=.001). Only TNM Stage 1 was significant for remission in the multivariate analysis.

CONCLUSION

The low remission rate in our DTC patients is probably due to more advanced disease at time of presentation. Early detection may, therefore, be essential in improving outcome.

Changing patterns of thyroid carcinoma

BACKGROUND

To assess changing trends in histological types of thyroid cancer in an Irish hospital over the past 30 years.

METHODS

Biographical data, tumour characteristics, treatment and outcome from 190 patients with thyroid carcinoma from 1970 to 2000 were reviewed retrospectively.

RESULTS

Detailed records of 190 patients with thyroid cancer were identified with a mean age at presentation of 50 years. From 1970 to 1979 the distribution of histological types was: papillary carcinoma; 9 patients (4.7%), follicular; 17 patients (8.9%), anaplastic; 9 patients (4.7%), medullary; 1 patient (0.5%) and lymphoma; 1 patient (0.5%). From 1980 to 1989 papillary carcinoma accounted for 32 patients (16.8%), follicular; 14 patients (7.3%), anaplastic; 13 patients (6.8%), medullary; 7 patients (3.7%) and lymphoma; 5 patients (2.6%). From 1990 to 1999 papillary cancer accounted for 48 patients (25.2%), follicular; 14 patients (7.3%), anaplastic; 8 patients (4.2%), medullary; 7 patients (3.7%) and lymphoma; 5 patients (2.6%). Survival rates were significantly better for those aged less than 45 years (P < 0.0001), female sex (P < 0.01) and those with papillary carcinoma (P < 0.01).

CONCLUSIONS

This study demonstrated a significant increase in the incidence of papillary carcinoma. This may be related to increasing dietary iodine intake and may be significant as papillary carcinoma is associated with a more favourable prognosis.

Follicular and Hürthle cell carcinoma of the thyroid gland

Follicular and Hürthle cell carcinoma of the thyroid gland are uncommon tumors that are genotypically similar. Current and future diagnostic adjuncts, treatment, and postoperative follow-up for patients with follicular and Hürthle cell cancer are outlined. Risk factors for recurrence and mortality and the reported outcomes of treatment of follicular and Hürthle cell carcinoma are reviewed.

Retrospective analysis of predictive factors for recurrence after curatively resected papillary thyroid carcinoma

PURPOSE

This retrospective study analyzes the predictive factors after curative surgery for papillary thyroid carcinoma (PTC).

METHODS

We analyzed 386 patients who underwent a curative operation for PTC in our hospital between 1977 and 1997, subject to the inclusion criteria.

RESULTS

According to univariate analysis, pathological lateral cervical lymph node involvement (P < 0.0001), dedifferentiation of the tumor (P < 0.002), male sex (P < 0.0001), a large tumor (P < 0.005), and an age of over 50 years (P < 0.05) were significant factors. Cox's proportional hazard model showed that a man (P < 0.05), aged over 50 years (P < 0.05), who had a large primary tumor (P < 0.05) with dedifferentiation (P < 0.05), and pathological lateral cervical lymph node metastasis (P < 0.005) was more likely to have recurrence of PTC.

CONCLUSIONS

Determining whether lymph node metastasis exists could be useful for predicting recurrence in patients who have undergone curative resection of PTC.

Predictive factors of thyroid carcinoma in non-toxic multinodular goitre

The management of nontoxic multinodular goitre (NMNG) remains controversial. The challenge for the clinician is to identify the small proportion of NMNG patients with associated thyroid carcinoma who would thus benefit from surgery. We studied retrospectively the medical records of 80 patients with NMNG and coexisting thyroid carcinoma who underwent total thyroidectomy. Eighty total thyroidectomy patients with NMNG whose histology was benign were then randomnly chosen as controls. In univariate analysis, the following parameters were significantly more frequent in the carcinoma group: rapid growth of the goitre (p = 0.002), presence of microcalcifications (p = 0.01), hypoechogenicity (p = 0.02), firm consistency of a nodule (p = 0.03), and presence of a dominant cold nodule on scintigraphy (p = 0.03). In the multiple regression analysis, the variables significantly associated with carcinoma were rapid growth (Odds ratio (OR) = 4.13, 95% confidence interval(CI): 1.72-9.89), hypo-echogenicity (OR = 3.11, 95% CI: 1.13-8.51) and the presence of a dominant nodule (OR = 2.26, 95% CI: 1.06-4.79)). In the cancer group, tumour size was positively correlated with compression signs (p = 0.01), age (p = 0.02), the presence of a dominant nodule on scintigraphy (p = 0.02), and with rapid growth (p = 0.04). Concerning nodule size estimated on US (ultrasound), the majority (65%) of patients without carcinoma had nodules < 3 cm, whereas 73% of patients with clinical thyroid carcinoma (> or = 1 cm on histology) had nodules with a diameter of > or = 3 cm on US (p = 0.02). In conclusion, our study suggests that surgical treatment of NMNG should be proposed in the presence of rapid nodular growth, compression signs, dominant nodule on scintigraphy, nodule size > or 3 cm and hypo-echogenicity.

Prevalence and clinico-epidemiology of familial Graves' disease in Japan based on nationwide epidemiologic survey in 2001

A nationwide epidemiologic survey of familial Graves' disease (GD) was conducted in 2001. "Familial GD" was defined as a patient who had at least one Graves' patient within the proband's first-degree relatives. The primary survey was performed for estimating the prevalence of patients among a random selection of 2367 departments/hospitals of internal medicine, endocrinology, thyroidology and pediatrics. Of those receiving the primary questionnaire, 1361 (57.5%) responded, and 902 familial GD patients who visited them in 2000 were reported. The total number of patients was estimated to be 2850 (95% confidence intervals: 2100-3600). Based on the nationwide survey concerning the prevalence of hyperthyroidism in 1999, 2.1-3.1% of hyperthyroidism appeared to be familial GD and the relative risk of familial GD was roughly estimated to be 19-42. Subsequently, a second survey was carried out for obtaining the clinicoepidemiologic features of those patients. Of 902 patients, 487 (54%) were reported. No significant differences between familial and non-familial GD were found in age and sex distributions, clinical features or laboratory findings. Familial GD possessed the highest association with Hashimoto's thyroiditis, approximately 8% within the first-degree relatives, suggesting a shared genetic predisposition. These findings confirm the familial clustering of GD in the Japanese population, indicating the importance of environmental factors, genetic factors or both in the development of the disease.

A population-based analysis of survival factors in differentiated and medullary thyroid carcinoma

OBJECTIVE

The study purpose was to determine survival and prognostic factors for differentiated thyroid carcinoma (DTC).

METHODS

Cases of DTC were extracted from the Surveillance, Epidemiology and End Results database from 1988 through 1998. Kaplan-Meier survival analysis was conducted for papillary, follicular, and medullary histologies. Cox proportional hazard analysis was used to examine the influence of age, gender, tumor size, local extension, and cervical node involvement on overall survival.

RESULTS

A total of 18,118 cases were identified, including 15,820 (87.3%) papillary carcinomas, 1799 (9.9%) follicular carcinomas, and 499 (2.8%) medullary carcinomas. Mean survival (10-year survival) was 122 (87.7%), 117 (80.2%), and 108 (73.7%) months for papillary, follicular, and medullary tumors, respectively. For each histology, increasing age, male gender, and degree of local extension substantially reduced survival. Cervical metastasis did not influence survival for papillary or follicular carcinomas but approached significance for medullary carcinoma (P = 0.065).

CONCLUSIONS

Degree of local extension in thyroid carcinoma should be subclassified to more accurately determine prognosis. Treatment of the neck should be considered for medullary thyroid carcinoma.

Socioeconomic factors and the presentation, management, and outcome of patients with differentiated thyroid carcinoma

To determine whether patients from disadvantaged socioeconomic groups present with more advanced thyroid carcinoma or experience differing management and clinical outcomes, we retrospectively reviewed the charts of 292 patients seen at MD Anderson Cancer Center and Ben Taub General Hospital between 1987 and 1994. At diagnosis, the mean age was 42 +/- 16 years, 78% of patients were female, 76% of patients were low risk (TNM stage I or II), and 22% high risk (stage III or IV). Neighborhood income (+/- standard error of the mean [SEM]) (1990 census data) was lower in the high-risk group compared with the low-risk group (US dollars 26200 +/- 1670 vs. US dollars 30900 +/- 870, p = 0.012). Men were more likely than women to present at an older age (47.5 +/- 16.7 vs. 40.2 +/- 16.0, p = 0.0014) and in the high-risk group (46% vs. 15%, p < 0.0001). No socioeconomic factor (ethnicity, marital status, occupation prestige, neighborhood income, insurance type) influenced initial diagnostic assessment. Similarly, no socioeconomic factor influenced initial disease management or the type of follow-up received over the 12-year period. Married patients had a lower 5-year recurrence rate than those unmarried (18% vs. 32%, p = 0.03); however, this did not affect overall or disease-specific survival. Similarly, ethnicity, marital status, occupation prestige, and insurance type did not influence overall or disease-specific survival. Although 10-year overall survival rates were lower in patients in the lowest income quartile (57% vs. 70% for upper, p = 0.0024) and in men compared with women (39% vs. 76%, p < 0.0001), gender alone influenced 10-year disease-specific survival (80% for men, 89% for women, p = 0.047). In summary, no socioeconomic factor appears to affect initial treatment or follow-up pattern in patients with differentiated thyroid cancer. Income and gender may affect stage at initial disease presentation and may be risk factors affecting eventual clinical outcomes.

Conservative management of patients with intrathyroidal well-differentiated follicular thyroid carcinoma

BACKGROUND

Total or near-total thyroidectomy for the treatment of follicular thyroid carcinoma (FTC). The prognosis of patients with low-risk FTC, however, is excellent, and thus total thyroidectomy may not be justifiable in such patients.

METHODS

A retrospective review identified 61 patients diagnosed with intrathyroidal well-differentiated FTC between 1958 and 1991.

RESULTS

Median age at diagnosis was 42 years (range, 15-78 years). Most patients (90.2%) had a lobectomy or subtotal thyroidectomy. Median tumor size was 3.0 cm (range, 0.9-9.5 cm). Fifty-eight patients (95.1%) received thyroid hormone supplementation, and 5 (8.2%) received radioactive iodine ablation postoperatively. Median follow-up was 11 years (range, 3-35 years). Local recurrence, metastasis, or both developed in 3 patients (4.9%), and all subsequently died of thyroid cancer. The cumulative 10- and 15-year cancer-specific survival rate was 96.5%. Factors significantly related to worse survival were oxyphilic histology (log-rank, P =.00) and tumor size of more than 4 cm (P =.001). However, neither was found to be an independent predictor of outcome by Cox multivariate analyses (P =.7 and.9, respectively). The extent of initial operation (unilateral versus bilateral procedure) was not significantly related to survival (P =.52).

CONCLUSION

Conservative management consisting mainly of lobectomy or subtotal thyroidectomy and thyroid hormone supplementation is associated with favorable outcome of patients with intrathyroidal well-differentiated FTC.