Lymphocytic infiltration in juvenile thyroid carcinoma

Hashimoto's Thyroiditis and the Risk of Papillary Thyroid Cancer in Children

The association between Hashimoto's thyroiditis (HT) and pediatric thyroid cancer is controversial. Most studies examining this connection have been based on adults, and larger studies in children are lacking. We performed a retrospective study of all sequential pediatric patients who underwent a thyroidectomy for a neoplasm at our institution over a twenty-year period in order to explore the link between HT and pediatric thyroid cancer. A total of 153 patients, median age 16.5 (interquartile range [IQR] 14.2-18.3) years, underwent thyroid surgery for a neoplasm. Patients were mainly female (80%) and White (84%). Median follow-up was 58.6 (IQR 20.7-105.4) months. Thirty-five (23%) patients had HT. Patients who underwent thyroid surgery and had HT were more likely to harbor a malignant neoplasm (p = 0.05); specifically, papillary thyroid carcinoma (PTC, p = 0.02). There was a difference in the distribution of HT among the subtypes of PTC (p = 0.03). Despite this, there was no difference in terms of survival between patients with/without HT. In conclusion, children with a thyroid malignancy, specifically, PTC, are more likely to have HT. The association between HT and pediatric PTC appears to be subtype-specific but does not seem to affect patient survival.

Coexisting CLT in PTC is an independent predictor of tumor aggressiveness for patients aged under 55: a retrospective analysis of 635 patients

BACKGROUND

The study was aimed at investigating the potential role of chronic lymphocytic thyroiditis (CLT) in papillary thyroid cancer (PTC) aggressiveness for patients aged below 55, as well as to figure out factors influencing potential recurrence risk in different age groups.

METHODS

A total of 635 adult patients were retrospectively analyzed. 188 patients were diagnosed with coexistent CLT and the remaining 447 were classified as non-CLT. Then the characteristics of CLT-coexisted patients and non-CLT ones were compared respectively when patients were aged ≥ 55 years or below. The association among postoperative clinicopathological features were also analyzed using multivariate regression. In addition, the prognostic value of several variables relating to high-risk recurrence were estimated within different age groups.

RESULTS

When divided in two age groups (55 years as the borderline), non-CLT group (aged below 55 years) had a remarkable frequency of small size lesion (Dmax ≤ 1 cm) compared with CLT-coexisted patients (54.6% to 43.0%, p = 0.02). In addition, non-CLT patients tended to have intrathyroidal extension as opposed to those with coexistent CLT (20.2% to 28.2%, p = 0.05). In multivariate analysis, CLT still significantly acted as an independent risk factor of greater lesion size (Dmin > 1 cm) (OR = 1.7, p = 0.02) and mildly promoted gross extrathyroidal extension (ETE) (OR = 1.4, p = 0.06). However, associations didn't emerge in the characteristics mentioned above with CLT when patients were ≥ 55 years old. The prognostic value of CLT in high-risk recurrence was evident only in patients aged 35-44 years. (OR = 2.4, 95%CI:1.2-5.4, p = 0.02). Greater lesion size independently promoted gross ETE, no matter patients were aged above 55 years or not. Its prognostic value of high-risk recurrence was significant throughout all age groups.

CONCLUSION

These findings revealed that CLT coexistence might be the unfavorable factor of PTC aggressiveness in patients aged below 55 years. Its role as well as greater tumor size may potentially predict higher recurrence risk according to results figured out in the prediction model.

Chronic Lymphocytic Thyroiditis and Aggressiveness of Pediatric Differentiated Thyroid Cancer

OBJECTIVES/HYPOTHESIS

Hashimoto's Thyroiditis (HT) is a common cause of hypothyroidism. Among adults with differentiated thyroid cancer (DTC), HT appears to be associated with less severe disease burden. In the absence of information regarding HT and disease burden among children with DTC, we assessed the relationship between pediatric DTC severity and HT.

STUDY DESIGN

Retrospective cohort.

METHODS

Charts from 90 pediatric patients who underwent surgical removal of DTC from 2002 to 2017 at tertiary-care children's hospital were reviewed. Demographic, clinical, surgical, pathology, and outcome details were compared between patients with and without HT. Consistency among diagnostic modalities of HT was also evaluated.

RESULTS

Median age at presentation was 16.0 years (range 4.2-18.9 years). Twenty-two patients were male (24%). Forty-five patients (50%) had HT based on presence of thyroid autoantibodies and/or surgical pathology findings and 45 patients did not have HT. Patients with HT had increased odds of microcalcifications (odds ratio [OR]: 3.01, P = .031) and decreased odds of palpable nodules (OR: 0.212, P = .024) and T2 lesions (vs. T1) (OR: 0.261, P = .015) compared with non-HT. No significant differences in demographics and the incidence of multifocality, extrathyroidal extension, lymphovascular invasion, lymph node or pulmonary metastases, disease recurrence, or radioactive iodine treatment were found between the two groups. Thyroglobulin/thyroid peroxidase autoantibodies and surgical pathology indicative of HT were concordant in 82.4% (κ = 0.635, P < .001).

CONCLUSION

HT was present in 50% of children with DTC. Patients with DTC and HT presented with smaller tumors compared to non-HT patients. No significant differences in other markers of disease aggressiveness were found between the two groups.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Is there a correlation between thyroiditis and thyroid cancer?

BACKGROUND

In the past few decades, the incidence of thyroid cancer has increased significantly all over the world. In the same period, there also seems to have been an increase in the incidence of Hashimoto's Thyroiditis-the most common inflammatory autoimmune thyroid disease. Several studies have linked thyroiditis to thyroid cancer.

METHODS

In our study, we examined 2304 cases of thyroid surgery collected over a 12-year period starting from 2004. In 2090 cases (90.7%) out of our sample, it has been possible to compare the presence, or lack thereof, of thyroiditis by means of a histological diagnosis post-surgery; 214 (9.3%) cases were excluded from our study due to insufficient data. We then divided the different histological classifications into two groups. Group A included all the benign histological classifications and Group B included all the malignant histological classifications. In each group, we then assessed the presence, or lack thereof, of thyroiditis in order to evaluate if thyroiditis can be linked to a higher incidence of thyroid cancer.

RESULTS

Data analysis showed a higher incidence of thyroiditis in Group B, 36.4% (malignant pathology report), than in Group A, 32.4% (benign pathology report), but no statistically significant difference emerged between those two groups (P > 0.05).

CONCLUSIONS

Our conclusion was that a correlation between thyroiditis and a higher incidence of thyroid cancer is still undefined.

Chronic lymphocytic thyroiditis is associated with invasive characteristics of differentiated thyroid carcinoma in children and adolescents

BACKGROUND

The association between chronic lymphocytic thyroiditis (CLT) and thyroid cancer is an interesting topic. The aim of the present study was to evaluate if demographic and histological characteristics as well as the long-term outcome of thyroid cancer was different in children and adolescents with and without CLT.

METHODS

The medical records of children and adolescents (≤21 years old) were reviewed. The following data were recorded: gender, year and age at diagnosis, family history of thyroid cancer, history of external radiation therapy, histological type (papillary and variants, follicular and variants), tumour size, multifocality, infiltration of thyroid parenchyma or surrounding soft tissues, vascular invasion, presence of lymph node and distant metastases. Information about the presence of TgAb and TPOAb was also collected.

RESULTS

One hundred eight children and adolescents (median age 19.0, interquartile range 4.0 years) were diagnosed with differentiated thyroid carcinoma (DTC); 31 patients (28.7%) presented histological characteristics compatible with CLT. Infiltration of thyroid parenchyma was more frequent in patients with CLT compared to patients without (74.2% vs 48.1% respectively, P=0.024). Familial papillary thyroid carcinoma (PTC) was more frequent in patients with CLT compared to those without CLT (20.7% vs 2.8% respectively, P=0.009). There was no better outcome with respect to the presence of CLT or not.

CONCLUSIONS

Children and adolescents with CLT present more frequently familial PTC as well as thyroid cancer with invasive characteristics.

Infiltration of a mixture of immune cells may be related to good prognosis in patients with differentiated thyroid carcinoma

OBJECTIVE

Immune responses against differentiated thyroid carcinomas (DTC) have long been recognized. We aimed to investigate the role of immune cell infiltration in the progression of DTC.

DESIGN

We studied 398 patients - 253 with papillary and 13 with follicular thyroid cancers, as well as 132 with nonmalignant tissues.

PATIENTS AND MEASUREMENTS

Immune cell infiltration was identified using CD3, CD4, CD8, CD20, CD68 and FoxP3 immunohistochemical markers. In addition, we assessed colocalization of CD4 and IL-17 to identify Th17 lymphocytic infiltration and colocalization of CD33 and CD11b to identify infiltration of myeloid-derived suppressor cells (MDSC).

RESULTS

Immune cells infiltrated malignant tissues more often than benign lesions. The presence of chronic lymphocytic thyroiditis (CLT) concurrent to DTC, CD68+, CD4+, CD8+, CD20+, FoxP3+ and Th17 lymphocytes but not MDSCs was associated with clinical and pathological features of lower tumour aggressiveness and a more favourable patient outcome. A log-rank test confirmed an association between concurrent CLT, tumour-associated macrophage infiltration, and CD8+ lymphocytes and an increased in disease-free survival, suggesting that evidence of these immune reactions is associated with a favourable prognosis.

CONCLUSION

Our data suggest that the tumour or peri-tumoural microenvironment may act to modify the observed pattern of immune response. Immune cell infiltration and the presence of concurrent CLT helped characterize specific tumour histotypes associated with favourable prognostic features.

Well-differentiated thyroid carcinoma with concomitant Hashimoto's thyroiditis present with less aggressive clinical stage and low recurrence

Papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) are the most common differentiated thyroid cancers. Previous studies report that Hashimoto's thyroiditis (HT) concomitant with PTC is unusual and improves prognosis compared to classical PTC. Few previous studies address FTC concomitant with HT. In this study, we retrospectively analyzed data from one institution and compared clinical presentations and results of treatment of PTC and FTC with and without HT. In addition, studies comparing presentation and long term follow-up prognosis in classical PTC and FTC were conducted. A total of 1,788 PTC patients and 209 FTC patients underwent thyroidectomy with or without lymph node dissection and follow-up at Chang Gung Medical Center in Linkou, Taiwan. All thyroid carcinomas were pathologically classified according to World Health Organization criteria. Histological patterns of PTC were categorized as classical PTC, or PTC with HT. Follicular thyroid carcinoma patients were categorized as FTC or FTC with HT. The dataset contained a total of 1,703 PTC cases categorized as classical PTC, 85 cases of PTC with HT, 201 cases of FTC and eight cases of FTC with HT. Analysis of Classification of Malignant Tumors (TNM) stage revealed a higher percentage of classical PTC in stage IV than HT group (12.03% vs. 4.70%). Mean tumor size of classical PTC was larger than HT group. Although 42.3% of FTC cases presented with distant metastases, no cases of FTC with HT presented with distant metastasis. Cancer-specific mortality was higher in classical PTC group than in PTC with HT. There was 53.2% of FTC without HT assigned recurrent status, and six of them died of thyroid cancer. No cancer mortality or recurrence in HT with FTC. PTC and FTC with HT presented with better clinical stage and better prognosis after same therapeutic modality. In conclusions, both PTC and FTC with HT have less aggressive clinical presentation and better prognosis.

Increased numbers of tumor-lysing monocytes in cancer patients

Lymphatic infiltration is a well known phenomenon in different tumors including endocrine malignancies. However, little is known about the role of antigen-presenting cells and T cell activation in this context. The aim of our study was to investigate the quantity and function of CD14+/CD56+ monocytes in tumor patients including endocrine malignancies. First, these cells were characterized in peripheral blood of endocrine and non-endocrine cancer patients as well as in tumor tissue samples. Cancer patients had in mean 3.7 times more CD14+/CD56+ monocytes in the peripheral blood compared to healthy controls (p≤0.0001), while the highest frequencies were seen in patients with heavy tumor load. Importantly, these cells additionally expressed several NK cell markers. A proof of CD14+/CD56+ infiltrations into papillary thyroid carcinoma was shown by immunohistochemical analyses. Functional analyses revealed an apoptosis inducing capacity in vitro after IFN-α re-stimulation. Our data indicate the importance of tumor-lysing monocytes in antitumor immunity.

Clinical and pathological implications of concurrent autoimmune thyroid disorders and papillary thyroid cancer

Cooccurrences of chronic lymphocytic thyroiditis (CLT) and thyroid cancer (DTC) have been repeatedly reported. Both CLT and DTC, mainly papillary thyroid carcinoma (PTC), share some epidemiological and molecular features. In fact, thyroid lymphocytic inflammatory reaction has been observed in association with PTC at variable frequency, although the precise relationship between the two diseases is still debated. It also remains a matter of debate whether the association with a CLT or even an autoimmune disorder could influence the prognosis of PTC. A better understanding about clinical implications of autoimmunity in concurrent thyroid cancer could raise new insights of thyroid cancer immunotherapy. In addition, elucidating the molecular mechanisms involved in autoimmune disease and concurrent cancer allowed us to identify new therapeutic strategies against thyroid cancer. The objective of this article was to review recent literature on the association of these disorders and its potential significance.

Coexistence of chronic lymphocytic thyroiditis is associated with lower recurrence rates in patients with papillary thyroid carcinoma

OBJECTIVE

The effect of coexistent chronic lymphocytic thyroiditis (CLT) on prognosis in papillary thyroid carcinoma (PTC) patients remains controversial. We evaluated the influence of coexistent CLT on prognostic outcome and the association of coexistent CLT with clinicopathological parameters.

DESIGN

A retrospective study with a median follow-up of 70 months.

PATIENTS AND MEASUREMENTS

Patients with PTC who underwent total thyroidectomy followed by (131)I remnant ablation between 1995 and 2003 at Asan Medical Center, Seoul, Korea were enrolled. CLT was diagnosed histopathologically.

RESULTS

Among 1441 patients, 214 (14.9%) had coexistent CLT. A greater female preponderance was noted in the patients with CLT compared with those without CLT (P < 0.01). Mean tumour size in the patients with CLT was smaller than that in patients without CLT (2.0 +/- 1.2 vs. 2.2 +/- 1.4 cm; P = 0.02). One hundred and fifty-one (12.3%) patients without CLT had recurrence, whereas 14 (7.1%) patients with CLT had recurrence during the follow-up period (P = 0.016). In patients with cervical lymph node metastases, those with coexistent CLT showed a significantly lower recurrence rate than those without CLT (P = 0.012). However, this association was lost on multivariate analysis adjusting for other clinicopathological predictors for recurrence.

CONCLUSIONS

In this study, CLT was commonly associated with PTC and was associated with smaller size of the primary tumour at presentation. CLT was also associated with a reduced risk of recurrence during follow-up, although this was not significant after adjustment for other prognostic factors.

Carcinoma de tireóide na infância e adolescência

Aproximadamente 10% das neoplasias de tireóide aparecem abaixo dos 21 anos e representam 3% das neoplasias da infância, com predomínio em meninas (2F:1M). São papilíferos em 90% casos e mais freqüentemente bilaterais, multifocais e de maior dimensão. Invasão de cápsula e metástases ganglionar ou pulmonar são mais freqüentes que no adulto. O efeito carcinogênico da radiação é especialmente importante na criança pré-púbere. Em 5% dos casos de PTC existe história familial. Genes como o RET/PTC, RAS e BRAF estão habitualmente envolvidos na gênese do processo. A apresentação clínica pode ser nódulo cervical (90% casos) sem que represente um fator de pior prognóstico. O US e a PAAF são procedimentos diagnósticos valiosos. O tratamento deve ser cirúrgico (tireoidectomia total com esvaziamento ganglionar) seguido de PCI e radioterapia ablativa. A substituição com L-tiroxina deve objetivar a supressão crônica do TSH. O prognóstico ao longo prazo é melhor que no adulto. A quantificação da Tg plasmática também é útil na detecção da doença residual.

Carcinome de la thyroïdeet thyroïdite de Hashimoto

OBJECTIVES

To study of the association between thyroid carcinoma and Hashimoto's thyroiditis (HT).

MATERIAL AND METHODS

[corrected] Retrospective study of 78 patients undergoing surgery between 2001 and 2002, with a pathological diagnosis of Hashimoto's thyroiditis. The clinical data and complementary tests performed before surgery are reported.

RESULTS

The mean age was 44.6 years, with 77 females and only one male. There were 12 cases of thyroid cancer associated with HT, mostly with the nodular form, with 11 papillary carcinoma (14.1%) and one non-hodgkin B lymphoma of the thyroid. Tumor size varied from 4 to 60 mm with a mean of 26 mm. There was one microcancer (size<10 mm).

CONCLUSIONS

We did not find an increased incidence of thyroid cancer associated with this highly selected population of HT patients.

Lymphocytic infiltration in pediatric thyroid carcinomas

Lymphocytic thyroiditis has been associated with an increase in the incidence of thyroid papillary carcinoma in some reports, mostly series of both adults and children. Relatively little is written about thyroiditis and follicular carcinomas. We have seen several cases of pediatric follicular thyroid carcinomas, that had an associated lymphocytic infiltrate, which led us to examine all primary malignant thyroid neoplasms in our surgical files from 1984 through 2000 to examine this relationship. We also investigated the nature of the lymphocytic infiltrate with routine immunohistochemistry. Ten patients (five male, five female, ages 4.5-21 years of age) had a thyroid carcinoma resection, six (three males and three females) with papillary carcinoma and four patients (two males and two females) with low-grade follicular carcinoma. Seven samples (one male had two cases with tumor) from patients who had a papillary carcinoma resection with tissue blocks available were identified (one patient had slides but no blocks), as were all four patients with a follicular carcinoma. The thyroid of all patients with a follicular carcinoma contained a lymphocytic infiltrate; only four of the seven papillary carcinoma samples had an associated lymphoid infiltrate. In all cases with a lymphoid infiltrate, the infiltrate was present in both lobes (both adjacent and separate from the tumor). B lymphocytes were present in the lymphoid infiltrate of three of four patients with follicular carcinomas and in 1 of 3 cases of papillary carcinomas. T cells were dispersed throughout all the tumors with lymphoid infiltrates. We conclude that pediatric follicular carcinomas have an associated lymphocytic infiltrate in the tumor and/or adjacent thyroid, more commonly than papillary carcinomas.

Prospective pilot study of recombinant granulocyte-macrophage colony-stimulating factor and interferon-gamma in patients with inoperable hepatocellular carcinoma

Interferon (IFN)-gamma and Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) enhance tumor immunogenicity. The authors assessed tolerability and effectiveness of a combination therapy of these recombinant human (rh) cytokines in patients with inoperable hepatocellular carcinoma (HCC). In a monocentric, open, nonrandomized pilot study, rhGM-CSF (5 microg/kg qd, Monday and Tuesday) and rhIFN-gamma (100 microg qd, Wednesday and Thursday) were subcutaneously administered in 9-week cycles. Primary objective was survival, as secondary outcomes volumetric changes of tumor mass and biologic parameters reflecting systemic immunologic or local tumor responses were measured. Only patients with complete response (CR), partial response (PR), or stable disease (SD) proceeded to new treatment cycles. Fifteen patients (median 63 years, range 46-74 years, all men) were enrolled. Survival after the first cycle was 80% with SD in 9 of 15 patients (60%). PR was detected in one patient after the second cycle. Two patients finished five treatment cycles. Overall survival at 26 and 52 weeks was 40% and 20%, respectively. Median survival in patients with inducible HLA-DR on hepatoma cells (40%) was increased (42 weeks, 27-100) as compared with HLA-DR negative cases (60%; 13 weeks, 8-23; p < 0.0001), and a control group (p = 0.01). Parameters reflecting systemic immunomodulatory activities were not associated with clinical outcome. In 13 of 15 patients (87%), adverse events were reported, all less than grade 2 and none requiring therapy discontinuation. Immunotherapeutic approaches hold promise to prolong survival in selected patients with advanced HCC who respond by enhanced tumor immunogenicity.

The association between chronic lymphocytic thyroiditis and thyroid tumors

An association between lymphocytic thyroiditis and thyroid papillary carcinoma is still controversial. To assess the relationship, a histopathologic analysis of surgically resected thyroid tumors together with the frequency and severity of chronic lymphocytic infiltration of the thyroid among patients with follicular adenoma, follicular carcinoma, and papillary carcinoma was performed. The prevalence of lymphocytic infiltrate, which is indicative of autoimmune thyroiditis, was significantly higher in patients with papillary carcinoma (58%) than in patients with follicular carcinoma (20%) or follicular adenoma (14%). The lymphocytic infiltration within the tumor compared with the severity of thyroiditis in the nontumorous tissue. Therefore, the association between chronic lymphocytic thyroiditis and papillary carcinoma was confirmed. The possibility that an immunologic mechanism involved in the pathogenesis of papillary carcinoma stimulates lymphocytic infiltration in the thyroid tissue through an autoimmune mechanism is suggested.

Lack of IFN-gamma-mediated induction of the class II transactivator (CIITA) through promoter methylation is predominantly found in developmental tumor cell lines

Downregulation of major histocompatibility complex (MHC) molecules by tumor cells impairs cellular immune recognition and contributes to inefficient cell-mediated tumor eradication. Low or lack of expression of MHC molecules is frequently observed in early developmental or embryonically derived tumor cells. Considering the central role of the class II transactivator (CIITA) in MHC class II- and class I-mediated antigen presentation, we compared the induction of CIITA by interferon-gamma (IFN-gamma) in a diverse panel of developmental and more differentiated tumor cell lines. In contrast to the more differentiated tumor cell lines, none of the developmental tumor cell lines were capable of expressing CIITA after treatment with IFN-gamma. Remarkably, in transient transfection assays, CIITA promoter IV (CIITA-PIV) was found to be induced by IFN-gamma. Southern blot analysis of genomic DNA obtained from the developmental tumor cell lines indicated that the absence of endogenous CIITA induction was due to methylation of the CIITA-PIV region. Exposure to 5-azacytidine restored induction of CIITA and congruent HLA-DRA expression in these cells. The observation that only developmental tumor cell lines, originating from various tissues, employ methylation to silence CIITA expression may reflect the natural status of CIITA expression during early development rather than oncogenic transformation.

Anaplastic thyroid cancer with transient thyrotoxicosis: case report and literature review

A 55-year-old woman with anaplastic thyroid carcinoma presented with hyperthyroidism and neck swelling, hoarseness, and cervical lymphadenopathy. On physical examination, she was found to be clinically hyperthyroid with an enlarged, nontender multinodular goitre. Her serum thyroid hormone levels confirmed hyperthyroidism and technetium-99m pertechnetate scan failed to visualize the thyroid gland. Open biopsy showed an invasion of the thyroid gland by anaplastic thyroid carcinoma. The thyrotoxic phase lasted 60 days with predominantly increased thyroxine level and triiodothyronine/thyroxine (T3/T4) ratio decreased below 15. The thyrotoxic period was followed by subclinical hyperthyroidism and hypothyroidism which continued until she died of lung metastasis.

Influence of lymphocytic thyroiditis on the prognostic outcome of patients with papillary thyroid carcinoma

Both the association between lymphocytic thyroiditis (LT) and papillary thyroid carcinoma (PTC), and the prognostic significance of lymphocytic infiltrate in patients with thyroid malignancy, remain controversial. We examine the above relationships by retrospectively reviewing our series of patients treated for differentiated nonmedullary thyroid carcinoma at University of California-San Francisco over a 25-yr period (1970-1995). Of the 631 patients with complete data for analysis, 128 patients (20.3%) showed concomitant histologic evidence of LT and 503 patients (79.7%) had no evidence of LT. Prognostic outcome was assessed using Kaplan-Meier survival plots and analysis of risk factors by Cox's proportional-hazard modeling. The cohort with LT revealed a higher frequency of PTC (97.7% vs. 87.3%) and female patients (85.2% vs. 66.8%), a lower frequency of extrathyroidal invasion (7.8% vs. 23.3%) and nodal metastases (25.8% vs. 43.3%), and absence of distant metastases (0% vs. 4.8%), respectively, compared with those without LT. At initial surgery, a significantly greater proportion of patients with LT belonged to lower pathological tumor-node-metastasis stages, compared with those without LT (stage 1, 86.7% vs. 73%; stage 2, 4.7% vs. 8.3%; stage 3, 8.6% vs. 15.3%; and stage 4, 0% vs. 3.4%). Over a mean +/- SE follow-up period of 11.1 +/- 0.4 yr, patients with LT had significantly lower cancer recurrence rate (6.3% vs. 24.1%; P < 0.0001) and cancer mortality rate (0.8% vs. 8.0%; P = 0.001), respectively, compared with those without LT. In summary, our series showed a relatively common occurrence of LT in patients with PTC, and we believed that lymphocytic infiltration developed mainly in response to the tumor itself. We also found a more favorable course of PTC in the presence of LT; this supports the hypothesis that lymphocytic infiltration represents a form of immune reaction to control tumor growth and proliferation.

Lack of class II transactivator causes severe deficiency of HLA-DR expression in small cell lung cancer

Small cell lung cancer (SCLC) is characteristically not associated with tumour-infiltrating lymphocytes. Since SCLC has been reported to show marked reduction of class I HLA, the reduced expression has been considered a means of escaping anti-cancer immunity. However, HLA-DR expressed in cancer cells is now known to contribute to anti-cancer immunity. To clarify the difference in HLA-DR expression between SCLC and non-small cell lung cancer (NSCLC), and the mechanism, the expression and the cis- and trans-acting factors involved were investigated. HLA-DR was not immunohistochemically detected in any SCLC and could not be induced by interferon gamma (IFN-gamma) in any SCLC cell line, whereas HLA-DR was expressed to varying degrees and was easily induced in NSCLC. SCLC cell lines lacked class II transactivator (CIITA) even after IFN-gamma induction, whereas NSCLC cell lines expressed CIITA. The other class II HLA-specific transcription factors were expressed and genomic DNA of HLA-DR, including the promoter, was conserved well both in SCLC and in NSCLC cell lines. CIITA transfection improved the expression of HLA-DR in SCLC. In conclusion, the lack of CIITA results in severe deficiency of HLA-DR expression in SCLC. Since CIITA has also been reported to induce class I HLA, CIITA transfection might make it possible to establish effective anti-cancer immunotherapy against SCLC through the up-regulation of class I and class II HLA.

Coexistent thyroiditis is associated with lower tumour stage in thyroid carcinoma

BACKGROUND

Microsatellite instability (MSI) is a new mechanism described in carcinogenesis of several tumours and seems to predispose for cancer in some chronic inflammatory diseases. As thyroiditis is thought to be both the cause and the consequence of thyroid carcinoma, it was the aim of this retrospective study to investigate the epidemiology and the influence of a coexistent thyroiditis on prognosis and clinicopathological parameters in an iodine-deficient area.

METHODS

The grade of lymphocytic infiltration (LI) of 153 thyroid carcinomas was determined in paraffin-embedded tissues: G0 = no LI, G1 = peritumoral LI, G2 = peritumoral LI with follicle, G3 = diffuse LI. A non-radioactive PCR-based screening method was used for detection of MSI.

RESULTS

Twenty-seven (17.7%) out of 153 carcinomas were accompanied by thyroiditis (G1, 16; G2, 5; G3, 6). Ten cases fulfilled the criteria necessary for diagnosing Hashimoto's thyroiditis. Nine out of 10 (90%) Hashimoto's cases and 16 out of 17 (94%) other thyroiditis cases were associated with a significantly (chi2 < 0.01) lower pT stage (pT1, pT2) than cases without thyroiditis. No statistical association was found by comparing multifocality or sclerosing variants with the grade of lymphocytic infiltration. MSI was detected neither in patients with severe inflammation nor in the absence of thyroiditis.

CONCLUSIONS

MSI does not seem to play a role in the pathogenesis of thyroid carcinoma. Coexistent thyroiditis is associated with a lower pT stage and thus could be an indicator of a better prognosis.

Aberrantly expressed cytokeratin 1, a tumor-associated autoantigen in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is a somewhat puzzling disease, combining a propensity to metastasize with an indolent clinical course. The often pronounced T cell-dominated inflammatory infiltrate seen in PTC tumors has prompted us to search for signs of a tumor-induced immune response. In previous studies, we have demonstrated large tumor-specific deposits of IgG and complement in PTC tissue and isolated a putative target antigen. This investigation examines the presence of autoantibodies to cytokeratin 1, a high m.w. cytokeratin normally expressed only in suprabasal keratinocytes, in the serum and tumor tissue of PTC patients. Using immunoprecipitation and Western blot, cytokeratin 1-reactive autoantibodies were demonstrated in 80% of the PTC sera tested, and tumor-derived antibodies were shown to precipitate cytokeratin 1. Using immunohistochemistry, cytokeratins 1 and 10 were found in a large proportion of PTC tumors (39/44) but were absent from normal thyrocytes of most PTC-bearing glands. Our results indicate that this protein is expressed aberrantly in neoplastic cells and is immunogenic in this context.

Tumor-specific deposition of immunoglobulin G and complement in papillary thyroid carcinoma

Despite its predilection for multifocal growth and regional metastasis, papillary thyroid carcinoma (PTC) is a clinically indolent malignancy with an exceptionally favorable long-term prognosis. Together with the often striking inflammatory reaction present in PTC, its quiescent behavior has been suggested to reflect the activation of a tumor-induced immune response. To examine this possibility, we have studied the deposition of immunoglobulins and complement in PTC tissue. Samples from 70 cases of neoplastic and autoimmune thyroid diseases, including PTC (n = 41), follicular, anaplastic, and medullary carcinomas (n = 12), follicular adenoma (n = 6), Graves' disease (n = 8), and Hashimoto's thyroiditis (n = 3) were analyzed immunohistochemically. Cellular deposits of immunoglobulin G (IgG), particularly subclasses IgG1 and IgG4, and complement factors C3d, C4d, and C5 were shown in up to 80% of the PTC cases, whereas the other thyroid diseases studied showed little or no cellular deposition. Nonneoplastic tissue of PTC-containing thyroid glands (n = 22) lacked staining for IgG in 50% of the cases, and 82% were devoid of complement. The results suggest a tumor-specific immune response in PTC with activation of the classical complement cascade.

HLA-DR expression and lymphocytic infiltration in metastatic and non-metastatic papillary carcinoma of the thyroid

Thyrocyte HLA-DR expression in association with lymphocytic infiltration has been demonstrated in autoimmune diseases of the thyroid. HLA-DR expression has been noted both in association with lymphocytic infiltration and in its absence. However, no prognostic significance was attributed to these findings. The purpose of this study on papillary carcinoma of the thyroid was to examine how tumour behaviour relates independently to HLA-DR expression and lymphocytic infiltration. Fifty patients with papillary carcinoma with known metastatic status were examined for HLA-DR expression utilizing the immunoperoxidase conjugated indirect method. The patients were divided into three groups: no metastases (n = 16), regional lymph node metastases only (n = 25), and distant haematogenous metastases (n = 9). Overall HLA-DR expression was noted in 6, 36 and 55% of the respective groups. Tumour HLA-DR expression without lymphocytic infiltration was noted in 0, 4 and 33% of the respective groups. Tumour HLA-DR expression with lymphocytic infiltration occurred in 6, 32 and 22% of the respective groups. From these findings we conclude that HLA-DR expression with lymphocytic infiltration occurs more frequently than HLA-DR expression in the absence of infiltration. The concurrence of HLA-DR expression and lymphocytic infiltration is most commonly associated with regional lymph node metastasis. HLA-DR expression in the absence of lymphocytic infiltration occurs in tumours with distant haematogenous metastases and is an uncommon feature of tumours that have not metastasized or have metastasized only to lymph nodes. Tumour HLA-DR expression in the absence of lymphocytic infiltration may indicate the potential for more aggressive behaviour.

Association of chronic lymphocytic thyroiditis and thyroid papillary carcinoma. A study of surgical cases among Japanese, and white and African Americans

BACKGROUND

An association between lymphocytic thyroiditis and thyroid papillary carcinoma is still controversial. To determine a definite statistical relation, a histopathologic study was performed on tissues from in three races, because there is a racial and age-related difference in the susceptibility to thyroiditis.

METHODS

The prevalence and severity of thyroiditis combined with adenomatous goiter, follicular adenoma, or papillary carcinoma was defined by examination of surgically resected materials from Japanese (626 patients), and white and African Americans (330 and 90 patients, respectively).

RESULTS

The prevalence of lymphocytic infiltrates, which are indicative of autoimmune thyroiditis, was significantly higher in patients with papillary carcinoma than in patients with adenomatous goiter or follicular adenoma among Japanese females (63.0%) and males (50.0%), white females (76.0%), and African American females (46.2%). Lymphocyte infiltration into the follicular adenoma or papillary carcinoma correlated with the severity of combined thyroiditis.

CONCLUSION

An association between chronic lymphocytic thyroiditis and papillary carcinoma was confirmed in the Japanese, and white and African American populations. The possibility of autoimmune thyroiditis as a predisposing factor for papillary thyroid carcinoma, is suggested.

HLA-D Antigen Expression and Langerhans' Cell Infiltrates in Thyroid Tumors

Papillary carcinomas (PCs) of thyroid are among the most common but least aggressive human malignancies. The factors explaining the indolence of these tumors are unknown but host-tumor immune interactions may play a role. This study was designed to determine if there is morphologic evidence of these. Frozen tissues collected from 21 PCs, 4 follicular adenomas (FAs), 4 follicular carcinomas (FCs), and 11 nodular hyperplasias (NHs) were stained immunohistochemically for HlLA-D antigens, lymphocyte, and macrophage markers; results were graded numerically. Paraffin-embedded tumors (35 PCs, 10 FAs, and 10 FCs) were stained for 5-100 protein to detect Langerhans' cells (LCs). Diffuse staining for HLA-D antigens and heavy mononuclear infiltrates were found more commonly in PCs compared to follicular neoplasms (FNs) or NHs. No consistent relationship was found between lymphocyte/macrophage infiltrates and expression of HLA-D antigens. The largest number of LCs was in PCs (median 11.8 cells/standard microscopic field [c/smf]), fewer cells were found in FA (3.7 c/smf), and the least in FC (0.05 c/smf). Features of host-tumor interaction including HLA-D expression and infiltrates with lymphocyte macrophages and LC are more strongly expressed in PC than other tumors. This may play a role in explaining their biological behavior.

T lymphocytes, CD68-positive cells and vascularisation in thyroid carcinomas

Immunohistochemical detection and quantification of CD3- and CD45RO-positive lymphocytes and CD68-positive cells in 75 thyroid carcinomas of follicular cell origin revealed rising levels for these parameters associated with dedifferentiation. A parallel trend towards reduction of vascularisation, determined as CD31-positive blood vessels, with decreasing differentiation became evident, statistically only significant when well-differentiated follicular and anaplastic carcinomas were compared. Positive correlations could be demonstrated between the density of CD68-, CD3-, and CD45RO-positive cells as well as between the density of CD68-, and CD3-, and CD45RO-positive cells and vascularisation. These correlations were expected, as the interaction of CD68-positive cells and T lymphocytes results in the production of angiogenesis factors, ultimately leading to better vascularisation of the tumour. Nevertheless, the tumour cells themselves are variously capable of producing angiogenic substances. The obvious lack of positive correlation between the density of tumour-infiltrating cells determined in this study and vascularisation, despite reduced vascularisation in less differentiated tumours that contained increasing numbers of tumour-infiltrating cells, seems to be due to functional heterogeneity of morphologically similar tumours.

Pediatric thyroid cancer after the Chernobyl disaster. Pathomorphologic study of 84 cases (1991-1992) from the Republic of Belarus

BACKGROUND

During the initial period after the Chernobyl accident, large amounts of radioactive iodine were released in fallout, resulting in serious exposure to the thyroid gland in the residents of areas around the nuclear power station. Beginning in 1990, a definite increase in the incidence of thyroid cancer was noted in children of the Republic of Belarus.

METHODS

Morphologic and clinical features of 84 cases of post-Chernobyl thyroid carcinoma in Belarussian children from 5 to 14 years of age are reported. The latent period for tumor development was 4-6 years, with a mean of 5.8 years.

RESULTS

Papillary carcinoma was found in 83 patients and medullary carcinoma in one. Besides typical papillary carcinoma (14%), solid (34%), follicular (33%), mixed (10%), and diffuse sclerosing (9%) variants were observed. The follow-up period ranged from 8 months to 2.5 years. One patient died, local recurrence developed in 2, and cervical lymph node metastases developed in 10. To date, the incidence of local recurrence or metastatic disease after surgery was significantly higher in patients 5-8 years of age and in residents of areas nearest to the Chernobyl station.

CONCLUSIONS

Post-Chernobyl pediatric thyroid carcinoma is characterized by a short latency, a higher proportion of tumors arising in young children, and an almost equal sex ratio. Microscopically, these tumors were usually aggressive, often demonstrating intraglandular tumor dissemination (92%), thyroid capsular and adjacent soft tissue invasion (89%), and cervical lymph node metastases (88%). Papillary carcinoma was diagnosed in 99% of cases, with an unusually high frequency of solid growth patterns. Morphologic changes in nonneoplastic thyroid tissue were present in 90% of the glands, and the most specific findings were vascular changes and perifollicular fibrosis.

Carcinoma of the thyroid at a young age--a review of 23 patients

Twenty-three children and adolescents with thyroid carcinoma who were 20 years old or younger at the time of initial treatment were followed for a mean time of 9.5 years. Of the tumours, 21 were papillary and two follicular carcinomas. The majority (91%) of the 23 cases showed extra-thyroidal extension of the tumour. An association with chronic thyroiditis was observed in 30% of the cases. There was no history of irradiation of the head and neck in any patients. Relapse occurred in eight patients, lung metastases in two and local recurrences in six; one patient died from lung metastases 3 months after initial treatment. Male patients, advanced stage of tumour, less differentiated histological features and DNA aneuploidy were associated with a higher frequency of relapse. The prognosis of thyroid carcinomas in children and adolescents is not so good as is generally believed.

Expression of MHC class II antigens in human lung cancer cells

Surgical specimens of lung cancers were examined immunopathologically for the expression of major histocompatibility complex class II (MHC-II) antigens in the tumor cells and their relationship to the lymphocytic infiltration. A lymphocytic infiltrate was frequently observed in the tumor tissue, though its intensity differed among the various histological types. MHC-II antigens were often demonstrated in tumors with a lymphocytic infiltrate. They were detected predominantly in the cytoplasm of tumor cells and to a lesser extent on the cell membranes. The emergence of the MHC-II-positive tumor cells was closely related to a local infiltration by lymphocytes including interferon-gamma (IFN-gamma)-producing T-cells. On the basis of the histological findings, an in vitro experiment was carried out. Four types of lung cancer cells were incubated with recombinant IFN-gamma in order to induce MHC-II antigens. MHC-II antigens (HLA-DR as well as HLA-DQ and HLA-DP antigens) were elicited in three cancer cell lines depending on the concentration of IFN-gamma. Immunoelectron microscopic study revealed that they were expressed on the surface of the cell membrane, though to a lesser extent than in the cytoplasm. It was considered that MHC-II antigens could be induced in some tumor cells in the immunological environment where IFN-gamma was secreted from T-cells and concentrated locally.

The utility of some modern techniques in understanding thyroid pathology

A number of evaluating techniques have moved from the research laboratory into the purview of the diagnostic pathologist and have been applied to the analysis of thyroid lesions. Some of these have already proved diagnostically and prognostically useful, whereas some have produced insights into pathogenesis of specific thyroid lesions and disorders. Rapid proliferation and application of these techniques should allow for increased understanding of human thyroid disease in the near future.

Diffuse sclerosing variant of papillary carcinoma of the thyroid. A histopathological study of four cases

We present four cases of an unusual diffuse sclerosing variant of papillary carcinoma of the thyroid occurring in Japanese women ranging in age from 17 to 42 years. Macroscopically, both lobes of the thyroid were involved, being diffusely enlarged and firm. Histologically, the tumor was characterized by squamous metaplasia of tumor cells, numerous psammoma bodies, extensive stromal fibrosis, severe lymphocytic infiltration with formation of lymph follicles, and thin bundles of smooth muscle cells in the fibrous stroma. The tumor islands were located mainly within the dilated lymphatic vessels and the metastatic tumor involved the bilateral cervical lymph nodes in all cases. It is assumed that papillary carcinoma of this type invades the thyroid lymphatics during the early stage and, without forming nodular lesions, disseminates to both lobes with extensive metastasis to the cervical lymph nodes. It should be noted that papillary carcinoma of this type often suggests chronic thyroiditis clinically because of the symmetrical enlargement of the thyroid and frequent positive anti-thyroid antibodies in the serum. Some workers have reported the prognosis to be unfavorable because of extensive lymphatic involvement, but the prognosis of this variant has not yet been defined.