Autoimmune thyroid disease elicited by NY-ESO-1 vaccination

Severe thyrotoxicosis induced by tislelizumab: a case report and literature review

Immune checkpoint inhibitors (ICIs) have made significant breakthroughs in the treatment of a variety of malignancies. As its use increases, the unique immune-mediated toxicity profile of ICls are becoming apparent. We report a case of immune-related endocrine adverse events (irAE) in a patient with hepatocellular carcinoma treated with anti-programmed cell death protein 1 (PD-1) (tislelizumab). Although many irAEs have been reported, few cases of severe thyrotoxicosis have been described after immunotherapy in the literature. We present the case of a 49-year-old male who experienced a Grade 3 tislelizumab-related adverse reaction according to Common Terminology Criteria for Adverse Events (CTCAE5.0) and received methylprednisolone, thiamazole, and levothyroxine sodium tablets. Early identification of irAEs, risk factors, regular monitoring, use of steroids and/or immunoglobulins, and adjuvant supportive care are critical to the clinical prognosis of patients. It should be underlined that the tumor benefits of ICI therapy outweigh the risks associated with ICI-induced endocrine disorders, and ICI treatment should not be stopped or delayed except in rare cases (adrenal crisis, severe thyrotoxicosis). The familiarity of healthcare professionals with irAEs of the thyroid when thyrotoxicosis occurs is important to facilitate an effective diagnosis and appropriate treatment of this increasingly common thyroid disorder.

The changing clinical spectrum of endocrine adverse events in cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several malignancies, improving patient survival and quality of life. Endocrinopathies have emerged as a clinically significant group of immune-related adverse events (IRAEs). Although the mechanism of ICI toxicities has not been clarified, inhibition of immune checkpoints reduces immune tolerance to autoantigens, resulting in the development of autoimmunity disorders. We report current evidence regarding endocrine IRAEs that may have diagnostic and therapeutic implications. Management should be focused on a multidisciplinary approach to reach a prompt diagnosis and an appropriate and safe treatment.

Amino acid sequence homology between thyroid autoantigens and central nervous system proteins: Implications for the steroid-responsive encephalopathy associated with autoimmune thyroiditis

•

Alpha-enolase, aldehyde reductase-I and dimethylargininase-I are SREAT autoantigens.

•

Molecular mimicry between thyroid and CNS autoantigens is hypothesized in SREAT.

•

Homology with TSH-R, Tg and TPO exists for 6, 27 and 47 of 46,809 CNS-proteins.

•

The above homologies are often in epitope-containing parts of thyroid autoantigens.

•

Most of the above proteins are expressed in CNS regions which are altered in SREAT.

A few patients with Hashimoto’s thyroiditis or Graves’ disease develop a multiform syndrome of the central nervous system (CNS) termed Hashimoto’s encephalopathy or steroid-responsive encephalopathy associated with autoimmune thyroid disease (HE/SREAT). They have high levels of thyroid autoantibodies (TgAb, TPOAb and/or TSH-R-Ab) in blood and cerebrospinal fluid. Autoantibodies against alpha-enolase, aldehyde reductase-I (AKRIA) and/or dimethylargininase-I (DDAHI), proteins expressed in the CNS among other tissues, were detected in the blood and, when searched, in the cerebrospinal fluid of HE/SREAT patients. Recently, we reported that alpha-enolase, AKRIA and DDAHI share local sequence homology with each of the three autoantigens (TgAb, TPOAb, TSH-R-Ab), often in epitope-containing segments of the thyroid autoantigens. We hypothesized that there might be additional CNS-expressed proteins homologous to thyroid autoantigens, possibly overlapping known epitopes of the thyroid autoantigens. We used bioinformatic methods to address this hypothesis.

Six, 27 and 47 of 46,809 CNS-expressed proteins share homology with TSH-R, Tg and TPO, respectively. The homologous regions often contain epitopes, and some match regions of thyroid autoantigens which have homology with alpha-enolase, AKRIA and/or DDAHI. Several of the aforementioned proteins are present in CNS areas that show abnormalities at neuroimaging in HE/SREAT patients. Furthermore, autoantibodies against some of the said six, 27 and 47 proteins were reported to be associated with a number of autoimmune diseases.

Not only we validated our hypothesis, but we think that such a variety of potential CNS targets for thyroid Ab against epitopes contained in regions that have local homology with CNS proteins may explain the polymorphic phenotypes of HE/SREAT. Only when elevated amounts of these Ab are synthesized and trespass the blood-brain barrier, HE/SREAT appears. This might explain why HE/SREAT is so relatively rare.

Distinct clinical features and prognosis between persistent and temporary thyroid dysfunctions by immune-checkpoint inhibitors

Immune-related adverse events in the thyroid glands (thyroid irAEs) during treatment with immune-checkpoint inhibitors (ICIs) are most frequent endocrine irAE. Thyroid irAE can be divided into that requiring continuous therapy for thyroid dysfunction (P-THY), and that requiring only temporal treatment (T-THY). However, predictive factors for those differential outcomes are unknown, and susceptibility of human leukocyte antigen (HLA) to thyroid irAE has never been investigated. This study aimed to elucidate clinical courses and prognosis of P-THY in comparison with T-THY in the aspect of thyroid immunity and HLA. Patients with P-THY (n = 15) that required L-T4 supplemental therapy for hypothyroidism for more than 3 months, and patients with T-THY who required no therapy or therapy within 1 month were enrolled in the study. Lower-value of TSH, higher-value of FT4, and lower value of TSH/FT4 were thought to be predictive markers to estimate P-THY. In addition, anti-thyroglobulin antibody (TgAb) levels were significantly higher in patients with P-THY than those in patients with T-THY. HLA-DPA1*01:03 and HLA-DPB1*02:01 allele, and their haplotype frequencies were significantly higher in patients with P-THY than those in controls. P-THY had better survival rate than T-THY. Pre-existing thyroid autoimmunity, the extent of thyroid dysfunction, and predisposing HLA were associated with the differential course of thyroid irAEs. It was suggested that thyroid function tests, TgAb, and HLA typing tests are useful for prediction of clinical course in thyroid irAEs.

Association between Immune Related Adverse Events and Outcome in Patients with Metastatic Renal Cell Carcinoma Treated with Immune Checkpoint Inhibitors

Simple Summary

Patients treated with immune-checkpoint inhibitors often experience a wide range of peculiar adverse events, called immune-related adverse events (irAEs). Lately, it has been described that the presence of irAEs may be associated with better clinical response to immunotherapy. The aim of our retrospective study was to observe the onset of the most common side effects and to evaluate their potential prognostic impact in a cohort of metastatic renal cell cancer patients treated with immunotherapy. We confirmed a correlation between irAEs and progression free survival in patients with cutaneous and thyroid adverse reactions as well as in patients that experienced two or more irAEs. Thus, the development of irAEs could act as a clinical marker of efficacy in metastatic renal cell patients treated with immunotherapy.

Abstract

Background: It has been reported that the occurrence of immune-related adverse events (irAEs) in oncological patients treated with immune-checkpoint inhibitors (ICIs) may be associated with favorable clinical outcome. We reported the clinical correlation between irAEs and the efficacy of ICIs in a real-world cohort of metastatic renal cell cancer (mRCC) patients. Methods: We retrospectively evaluated 43 patients with mRCC who were treated with nivolumab or with nivolumab plus ipilimumab. We considered seven specific classes of irAEs including pulmonary, hepatic, gastrointestinal, cutaneous, endocrine, rheumatological, and renal manifestations. We assessed progression-free survival (PFS) of specific irAEs classes compared to the no-irAEs group. Results: Twenty-nine out of 43 patients (67.4%) experienced a total of 49 irAEs registered. The most frequent irAE was thyroid dysfunction (n = 14). The median PFS after the beginning of therapy was significantly longer in patients with thyroid dysfunction and cutaneous reactions. In multivariate analysis, thyroid dysfunction was an independent factor for favorable outcome [HR: 0.29 (95% CI 0.11–0.77) p = 0.013]. Moreover, experiencing ≥2 irAEs in the same patient correlated in multivariate analysis with better outcome compared with none/one irAE [HR: 0.33 (95% CI 0.13–0.84) p = 0.020]. Conclusions: This retrospective study suggests an association between specific irAES (thyroid dysfunction and skin reaction) and efficacy of ICIs in metastatic RCC. Notably, multiple irAEs in a single patient were associated with better tumor response.

Predictive Biomarkers of Immune Checkpoint Inhibitors-Related Toxicities

The emergence and continuous development of immune checkpoint inhibitors (ICIs) therapy brings a revolution in cancer therapy history, but the major hurdle associated with their usage is the concomitant ICIs-related toxicities that present a challenge for oncologists. The toxicities may involve non-specific symptoms of multiple systems as for the unique mechanism of formation, which are not easily distinguishable from traditional toxicities. A few of these adverse events are self-limiting and readily manageable, but others may limit treatment, cause interruption and need to be treated with methylprednisolone or tumor necrosis factor-α (TNF-α) antibody infliximab, and even directly threaten life. Early accurate recognition and adequate management are critical to the patient's prognosis and overall survival (OS). Several biomarkers such as the expression of programmed cell death ligand 1 (PD-L1), tumor mutation burden (TMB), and microsatellite instability-high (MSI-H)/mismatch repair-deficient (dMMR) have been proved to be the predictors for anti-tumor efficacy of ICIs, but there is a gap in clinical needs for effective biomarkers that predict toxicities and help filter out the patients who may benefit most from these costly therapies while avoiding major risks of toxicities. Here, we summarize several types of risk factors correlated with ICIs-related toxicities to provide a reference for oncologists to predict the occurrence of ICIs-related toxicities resulting in a timely process in clinical practice.

Predictive and sensitive biomarkers for thyroid dysfunctions during treatment with immune-checkpoint inhibitors

Immune‐related adverse events (irAEs) are often seen during immune‐checkpoint inhibitor (ICI) treatment of various malignancies. Endocrine irAEs including thyroid dysfunctions are the most common irAEs, but their biomarkers remain unclear. In order to identify individuals who are susceptible to thyroid irAE for earlier diagnosis and appropriate follow‐up, the current study is aimed to investigate biomarkers of thyroid irAE. Herein, patients with advanced malignant diseases who received ICIs treatment were prospectively studied. Clinical and laboratory examination, thyroid function, and autoantibodies were evaluated at baseline, and every 4 wk after first treatment with ICIs. Cytokines/chemokines were measured at baseline and at 4 wk. In vivo effects of ICIs on experimental autoimmune thyroiditis were evaluated. Twenty‐six patients with malignant diseases who received ICIs treatment were enrolled in the study. Patients were divided into two groups: those who developed thyroid irAE, and those without irAEs. Comparing the two groups, early increase (≤4 wk) in serum thyroglobulin (Tg) levels and thyroid autoantibodies was seen in thyroid irAE (P < .05). Notably, higher levels of serum IL‐1β, IL‐2, and GM‐CSF at baseline, and early decrease of IL‐8, G‐CSF, and MCP‐1 were significantly associated in the development of thyroid irAE (P < .05). In vivo effects of anti‐PD‐1 antibody on deterioration of mice experimental thyroiditis were seen. In conclusion, early change in Tg, thyroid autoimmunity, and cytokine levels might indicate development of thyroid irAE. Pre‐existing thyroid autoimmunity might be involved with the development of thyroid irAE. Potential application of these factors as surrogate biomarkers for tumor therapy was indicated.

New insight in endocrine-related adverse events associated to immune checkpoint blockade

Anticancer immunotherapy, in the form of immune checkpoint inhibition, is a paradigm shift that has transformed the care of patients with different types of solid and hematologic cancers. The most notable improvements have been seen in patients with melanoma, non-small-cell lung, bladder, renal, cervical, urotherial, and colorectal cancers, Merkel cell carcinoma, and Hodgkin lymphoma. Monoclonal antibodies (mAbs) targeting immune checkpoints (i.e., anti-CTLA: ipilimumab; anti-PD-1: nivolumab, pembrolizumab; anti-PD-L1: durvalumab, atezolizumab, avelumab) unleash the immune system against tumor cells targeting mainly T cells. Treatment with immune checkpoint inhibitors (ICIs) is associated with a variety of diverse and distinct immune-related adverse events (irAEs), reflecting the mechanistic underpinning of each target (i.e., CTLA-4, and PD-1/PD-L1 network). The most frequent endocrine irAEs associated with anti-PD-1 mAb treatment are thyroid dysfunctions, whereas hypophysitis is mostly linked to anti-CTLA-4 treatment. Type 1 diabetes mellitus and adrenalitis are rare irAEs. Combination therapy (anti-CTLA-4 plus anti-PD-1/PD-L1) can be associated with an increased risk and prevalence of endocrine irAEs. In this paper we discuss the pathophysiological and clinical aspects of irAEs with specific emphasis on endocrine irAEs associated with ICIs. With a growing number of patients treated with ICIs, a tight collaboration among oncologists, endocrinologists and immunologists appears necessary when the circumstances are more challenging and for better management of severe endocrine irAEs. Further investigations are urgently needed to better understand the mechanisms by which different ICIs can induce a variety of endocrine irAEs.

Comprehensive research on thyroid diseases associated with autoimmunity: autoimmune thyroid diseases, thyroid diseases during immune-checkpoint inhibitors therapy, and immunoglobulin-G4-associated thyroid diseases

Various thyroid diseases are associated with autoimmunity. Major autoimmune thyroid diseases are Graves' disease (GD) and Hashimoto's thyroiditis (HT). Thyrotropin receptor is an autoantigen in GD, and its immunogenicity has been examined. Immune-checkpoint inhibitor (ICI) is recently widely used for treatment of malignant tumors, but cases of thyroid diseases during ICI treatment have been increasing. Thyroid diseases during ICI therapy have been investigated in immunological and clinical aspects, and their Japanese official diagnostic guidelines were established. In addition, serum and tissue immunoglobulin-G4 levels have been examined in association with clinicopathological characteristics in GD, HT, and Riedel's thyroiditis. We review these diseases associated with thyroid autoimmunity and comprehensively discuss their potential application in future research and therapeutic options.

Correlation between thyroid transcription factor-1 expression, immune-related thyroid dysfunction, and efficacy of anti-programmed cell death protein-1 treatment in non-small cell lung cancer

Background

Recent studies have suggested a correlation between immune-related thyroid dysfunction (irTD) and the superior efficacy of anti-programmed cell death protein-1 (anti-PD-1) treatment in non-small cell lung cancer (NSCLC). Embryologically, the lung and thyroid are similar in origin, and thyroid transcription factor-1 (TTF-1) expresses in both organs, including NSCLC. We explored our hypothesis that TTF-1 expression in NSCLC might correlate with irTD incidence and anti-PD-1 treatment efficacy.

Methods

We identified 132 patients with NSCLC treated with anti-PD-1 antibody at our hospital between December 2015 and June 2017. We evaluated TTF-1 expression in tumor by immunohistochemistry using a mouse monoclonal antibody (clone 8G7G3/1, 1:100, Dako). IrTD was defined as two or more successive abnormal levels of thyroid-stimulating hormone (TSH) during anti-PD-1 treatment. We retrospectively assessed correlations between TTF-1 expression in tumor, irTD incidence, and anti-PD-1 treatment efficacy.

Results

Of 132 patients, 67 (51%) and 65 (49%) were positive and negative for TTF-1, respectively. We observed irTD in 19 patients (6 positives and 13 negatives for TTF-1). The incidence of irTD was 9% and 20% in TTF-1-positive and TTF-1-negative NSCLCs, respectively (P=0.086). Particularly, in non-squamous (NSQ) cell carcinomas, the irTD incidence was significantly higher in patients negative for TTF-1 (30%) than in those positive for TTF-1 (9%; P=0.010), and TTF-1 expression was identified as a significant risk factor for irTD on multivariate logistic regression analysis [odds ratio (OR), 0.18; 95% confidence interval (CI), 0.05-0.59; P=0.005]. Furthermore, longer median progression-free survival (10.3 months) was observed in patients with TTF-1-negative NSCLC with irTD compared to those with TTF-1-positive NSCLC with irTD, TTF-1-positive NSCLC without irTD, and TTF-1-negative NSCLC without irTD (4.2, 1.4, and 2.4 months, respectively).

Conclusions

TTF-1 expression in NSCLC might correlate with irTD and anti-PD-1 treatment efficacy.

Fulminant Type 1 Diabetes Mellitus Accompanied by Positive Conversion of Anti-insulin Antibody after the Administration of Anti-CTLA-4 Antibody Following the Discontinuation of Anti-PD-1 Antibody

An 80-year-old woman with malignant melanoma received 20 cycles of anti-programmed death 1 (PD-1) antibody (nivolumab) treatment and showed normal glucose tolerance. Three weeks after switching to anti-cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) antibody (ipilimumab), her plasma glucose level was elevated to 639 mg/dL, her HbA1c was 7.7%, and her fastening serum C-peptide immunoreactivity was undetectable. Anti-glutamic acid decarboxylase and insulinoma-associated protein-2 antibodies were negative. She was diagnosed with fulminant type 1 diabetes mellitus (F1DM). Remarkably, her anti-insulin antibody was positively converted, and her Sialylated Carbohydrate Antigen, Krebs von den Lungen-6 levels increased after ipilimumab therapy. She possessed F1DM-susceptible Human Leukocyte Antigen-DR4. A fluorescence activated cell sorting analysis showed an altered T-cell population. This case of F1DM highlights specific mechanisms underlying pancreatic beta cell immunity.

Thyroid dysfunctions secondary to cancer immunotherapy

BACKGROUND

Immunotherapy is a firmly established pillar in the treatment of cancer, alongside the traditional approaches of surgery, radiotherapy, and chemotherapy. Like every treatment, also cancer immunotherapy causes a diverse spectrum of side effects, collectively referred to as immune-related adverse events.

OBJECTIVE

This review will examine the main forms of immunotherapy, the proposed mechanism(s) of action, and the incidence of thyroid dysfunctions.

METHODS

A comprehensive MEDLINE search was performed for articles published up to March 30, 2017.

RESULTS

Following the pioneering efforts with administration of cytokines such as IL-2 and IFN-g, which caused a broad spectrum of thyroid dysfunctions (ranging in incidence from 1 to 50%), current cancer immunotherapy strategies comprise immune checkpoint inhibitors, oncolytic viruses, adoptive T-cell transfer, and cancer vaccines. Oncolytic viruses, adoptive T-cell transfer, and cancer vaccines cause thyroid dysfunctions only rarely. In contrast, immune checkpoint blockers (such as anti-CTLA-4, anti-PD-1, anti-PD-L1) are associated with a high risk of thyroid autoimmunity. This risk is highest for anti-PD-1 and increases further when a combination of checkpoint inhibitors is used.

CONCLUSIONS

Cancer patients treated with monoclonal antibodies that block immune checkpoint inhibitors are at risk of developing thyroid dysfunctions. Their thyroid status should be assessed at baseline and periodically after initiation of the immunotherapy.

Thyroid Autoimmunity and Lichen

Lichen planus (LP) and lichen sclerosus (LS) are cutaneous-mucous diseases with uncertain epidemiology. Current data, which are likely to be underestimated, suggest a prevalence in the general population of 0.1-4% for cutaneous LP, 1.27-2.0% for oral LP, and 0.1-3.3% for LS. While etiology of lichen is still unknown, clinical and histological evidence show an (auto)immune pathogenesis. Association of lichen with autoimmune thyroid disease (AITD) has been investigated in few studies. This association appears better defined in the case of LS, while is more controversial for LP. In both situations, the frequency of the association is higher in females. We review the available literature on the correlation between the different types of lichen and AITD, and the literature on the genetic risk factors which are shared by both conditions. Such data suggest that a common pathogenic mechanism could be the cause for co-occurrence of lichen and AITD, at least in some patients. Additionally, analyzing literature data and in continuity with our previous work on other autoimmune diseases, we suggest that molecular mimicry could trigger both diseases, and thus explain their co-occurrence.

Certain HLA alleles are associated with stress-triggered Graves' disease and influence its course

There are no studies on HLA analysis in patients in whom Graves' disease (GD) hyperthyroidism has been preceded by ≥1 stressful event. The aim of the present study was to identify predisposing or protecting HLA alleles and their effects on the course of GD in this subset of patients. We performed serological HLA typing in 58 Caucasian patients with stress-related GD and in 130 matched healthy controls (HC). We also performed genomic HLA typing in 20/58 patients and in all HC. Five HLA alleles and three loci were more frequent in patients compared to HC: B8, Cw7, C*07, C*17, DR3, DR4, DRB1*04, and DQ2. In contrast, B14 was less frequent in patients than in HC. Depending on outcome after ATD withdrawal (remission, exacerbation on-ATD, relapse off-ATD), in patients, some alleles/loci were over-represented, while others were under-represented. Age, FT3, and FT4 fold increase over the upper normal limit at onset were different depending on the allele/locus carried. In GD patients with stress-triggered hyperthyroidism, HLA typing may be helpful in predicting the outcome of the disease after ATD withdrawal.

Ipilimumab-induced hypophysitis in melanoma patients: an Australian case series

BACKGROUND

Ipilimumab (Yervoy; Bristol-Myers Squibb) is a novel fully humanised monoclonal antibody that blocks cytotoxic T-lymphocyte antigen 4, an immune checkpoint molecule, to augment anti-tumour T-cell responses. It is associated with significant immune-related side-effects including hypophysitis.

AIM

We reviewed the clinical and biochemical characteristics of 10 patients with ipilimumab-induced hypophysitis (IH), and developed guidelines for the early detection and management of IH based on our experiences at three major teaching hospitals in Sydney.

METHODS

All patients were evaluated at the Crown Princess Mary Cancer Centre and Department of Endocrinology, Westmead Hospital, Department of Endocrinology, Royal Prince Alfred Hospital, the Melanoma Institute Australia and Macarthur Cancer Therapy Centre, Campbelltown Hospital from 2010 to 2014. Relevant data were extracted by review of medical records. Main outcome measures included clinical features, hormone profile and radiological findings associated with IH, and presence of pituitary recovery.

RESULTS

Ten patients were identified with IH. In four patients who underwent monitoring of plasma cortisol, there was a fall in levels in the weeks prior to presentation. The pituitary-adrenal and pituitary-thyroid axes were affected in the majority of patients, with the need for physiological hormone replacement. Imaging abnormalities were identified in five of 10 patients, and resolved without high-dose glucocorticoid therapy. To date, all patients remain on levothyroxine and hydrocortisone replacement, where appropriate.

CONCLUSIONS

There is significant morbidity associated with development of IH. We suggest guidelines to assist with early recognition and therapeutic intervention.

Thyrotropin Receptor Epitope and Human Leukocyte Antigen in Graves' Disease

Graves' disease (GD) is an organ-specific autoimmune disease, and thyrotropin (TSH) receptor (TSHR) is a major autoantigen in this condition. Since the extracellular domain of human TSHR (TSHR-ECD) is shed into the circulation, TSHR-ECD is a preferentially immunogenic portion of TSHR. Both genetic factors and environmental factors contribute to development of GD. Inheritance of human leukocyte antigen (HLA) genes, especially HLA-DR3, is associated with GD. TSHR-ECD protein is endocytosed into antigen-presenting cells (APCs), and processed to TSHR-ECD peptides. These peptide epitopes bind to HLA-class II molecules, and subsequently the complex of HLA-class II and TSHR-ECD epitope is presented to CD4+ T cells. The activated CD4+ T cells secrete cytokines/chemokines that stimulate B-cells to produce TSAb, and in turn hyperthyroidism occurs. Numerous studies have been done to identify T- and B-cell epitopes in TSHR-ECD, including (1) in silico, (2) in vitro, (3) in vivo, and (4) clinical experiments. Murine models of GD and HLA-transgenic mice have played a pivotal role in elucidating the immunological mechanisms. To date, linear or conformational epitopes of TSHR-ECD, as well as the molecular structure of the epitope-binding groove in HLA-DR, were reported to be related to the pathogenesis in GD. Dysfunction of central tolerance in the thymus, or in peripheral tolerance, such as regulatory T cells, could allow development of GD. Novel treatments using TSHR antagonists or mutated TSHR peptides have been reported to be effective. We review and update the role of immunogenic TSHR epitopes and HLA in GD, and offer perspectives on TSHR epitope specific treatments.

Development of thyroglobulin antibodies after GVAX immunotherapy is associated with prolonged survival

Cancer immunotherapy induces a variety of autoinflammatory responses, including those against the thyroid gland, which can be exploited to predict clinical outcomes. Considering the paucity of information about thyroid autoimmunity in patients receiving cancer vaccines, we designed our study to assess the development of thyroglobulin antibodies (TgAbs) in patients treated with GVAX (vaccine made of a tumor cell type transfected with GM-CSF) and/or ipilimumab and correlated seroconversion with survival. Using both in house and commercial ELISA assays, we measured TgAbs in patients with pancreatic (No. = 53), prostate (No. = 35) or colon (No. = 8) cancer, before and after treatment with GVAX only (No. = 34), GVAX plus ipilimumab (No. = 42) or ipilimumab (No. = 20), and correlated their levels with patient's survival, disease status and T-cell surface markers. Antibodies to thyroperoxidase, myeloperoxidase, proteinase 3, insulin and actin were also measured. TgAbs specifically developed after GVAX, independent of the underlying cancer (81% in prostate, 75% colon cancer and 76% pancreatic cancer) and co-administration of ipilimumab (75% in GVAX only and 78% in GVAX plus ipilimumab). This TgAbs seroconversion could be detected mainly by the in house assay, suggesting that the thyroglobulin epitopes recognized by the antibodies induced by GVAX are different from the epitopes seen in the classic form of Hashimoto thyroiditis. Notably, TgAbs seroconversion was associated with significantly prolonged survival (p = 0.01 for pancreas and p = 0.005 for prostate cancer). In conclusion, GVAX immunotherapy induces the appearance of TgAbs that recognize a unique antigenic repertoire and associate with prolonged survival.