Knowledge domains and emerging trends in immune-related adverse events from immune checkpoint inhibitors: A bibliometrics and visualized analysis

Objective

The primary objective of this paper is to investigate the research hotspots and future trends of immune-related adverse events induced by immune checkpoint inhibitors, offering valuable insights for researchers in this field.

Methodology

Using the visual analysis software, this study conducted quantitative statistics and visualization research on the relevant literature concerning immune-related adverse events caused by immune checkpoint inhibitors in the Web of Science Core Collection Database. By evaluating the publication trends, countries, institutions, keywords, research status, cited documents, and document co-citations, among several others, the discussion revolved around the hot spots and future development trends in this field and provided references for future research.

Findings and conclusions

A total of 514 English articles were included, and the top three countries in the research field at the time of this study were the United States, Japan, and China. More specifically, the University of Texas MD Anderson Cancer Center, Dana-Farber Cancer Institute, and Massachusetts General Hospital have been the top three research institutes with more than 10 publications. The frequency of keyword use linked to immune-related adverse events caused by immune checkpoint inhibitors in literature research has been steadily growing over the years. Additionally, the research with respect to the disease focuses on melanoma, cell lung cancer, hepatocellular carcinoma, and breast cancer. In the context of drugs, cancer-related research has mainly focused on the combined use of nivolumab, pembrolizumab, ipilimumab, and immune checkpoint inhibitors. Meanwhile, research on adverse events has delved into the immune checkpoint inhibitors causing vitiligo, thyroid dysfunction, pancreatitis, cholangitis, and rheumatism. Related studies cover acute arthritis, myositis, acute kidney injury, as well as the combination therapy of immune checkpoint inhibitors and docetaxel, management of irAEs in cancer immunotherapy, and biomarkers of immune adverse reactions of immune checkpoint inhibitors. Finally, case report studies of immune adverse reactions caused by immune checkpoint inhibitors could serve as research hotspots in the future.

Targeting post-translational modifications of Foxp3: a new paradigm for regulatory T cell-specific therapy

A healthy immune system is pivotal for the hosts to resist external pathogens and maintain homeostasis; however, the immunosuppressive tumor microenvironment (TME) damages the anti-tumor immunity and promotes tumor progression, invasion, and metastasis. Recently, many studies have found that Foxp3+ regulatory T (Treg) cells are the major immunosuppressive cells that facilitate the formation of TME by promoting the development of various tumor-associated cells and suppressing the activity of effector immune cells. Considering the role of Tregs in tumor progression, it is pivotal to identify new therapeutic drugs to target and deplete Tregs in tumors. Although several studies have developed strategies for targeted deletion of Treg to reduce the TME and support the accumulation of effector T cells in tumors, Treg-targeted therapy systematically affects the Treg population and may lead to the progression of autoimmune diseases. It has been understood that, nevertheless, in disease conditions, Foxp3 undergoes several definite post-translational modifications (PTMs), including acetylation, glycosylation, phosphorylation, ubiquitylation, and methylation. These PTMs not only elevate or mitigate the transcriptional activity of Foxp3 but also affect the stability and immunosuppressive function of Tregs. Various studies have shown that pharmacological targeting of enzymes involved in PTMs can significantly influence the PTMs of Foxp3; thus, it may influence the progression of cancers and/or autoimmune diseases. Overall, this review will help researchers to understand the advances in the immune-suppressive mechanisms of Tregs, the post-translational regulations of Foxp3, and the potential therapeutic targets and strategies to target the Tregs in TME to improve anti-tumor immunity.

The immunoregulation effect of tumor microenvironment in pancreatic ductal adenocarcinoma

Pancreatic cancer has the seventh highest death rate of all cancers. The absence of any serious symptoms, coupled with a lack of early prognostic and diagnostic markers, makes the disease untreatable in most cases. This leads to a delay in diagnosis and the disease progresses so there is no cure. Only about 20% of cases are diagnosed early. Surgical removal is the preferred treatment for cancer, but chemotherapy is standard for advanced cancer, although patients can eventually develop drug resistance and serious side effects. Chemoresistance is multifactorial because of the interaction among pancreatic cancer cells, cancer stem cells, and the tumor microenvironment (TME). Nevertheless, more pancreatic cancer patients will benefit from precision treatment and targeted drugs. This review focuses on the immune-related components of TME and the interactions between tumor cells and TME during the development and progression of pancreatic cancer, including immunosuppression, tumor dormancy and escape. Finally, we discussed a variety of immune components-oriented immunotargeting drugs in TME from a clinical perspective.

Nobel Prize for immune checkpoint inhibitors, understanding the immunological switching between immunosuppression and autoimmunity

INTRODUCTION

Immune checkpoint inhibitors (ICIs) are a revolutionary form of immunotherapy in cancer. However, the percentage of patients responding to therapy is relatively low, while adverse effects occur in a large number of patients. In addition, the therapeutic mechanisms of ICIs are not yet completely described.

AREAS COVERED

The initial view (articles published in PubMed, Scopus, Web of Science, etc.) was that ICIs increase tumor-specific immunity. Recent data (collected from the same databases) suggest that the ICIs pharmacotherapy actually extends beyond the topic of immune reactivity, including additional immune pathways, such as disrupting immunosuppression and increasing tumor-specific autoimmunity. Unfortunately, there is no clear delimitation between these specific autoimmune reactions that are therapeutically beneficial, and nonspecific autoimmune reactions/toxicity that can be extremely severe side effects.

EXPERT OPINION

Immune checkpoint mechanisms perform a non-selective immune regulation, maintaining a dynamic balance between immunosuppression and autoimmunity. By blocking these mechanisms, ICIs actually perform an immunological reset, decreasing immunosuppression and increasing tumor-specific immunity and predisposition to autoimmunity. The predisposition to autoimmunity induces both side effects and beneficial autoimmunity. Consequently, further studies are necessary to maximize the beneficial tumor-specific autoimmunity, while reducing the counterproductive effect of associated autoimmune toxicity.

Seronegative autoimmune enteropathy with duodenal sparing and colonic clues in an adult female

Autoimmune enteropathy (AIE) is a rare immune disorder of the gut seldom found in adults and characterized by uncontrollable diarrhea resulting in malabsorption. While AIE is known to be pan-enteric, virtually all cases have presented with altered duodenal histology following known patterns with or without macroscopic change. We describe a unique case of seronegative AIE lacking typical duodenal manifestations in a 43-year-old female. To our knowledge, this is the first report of AIE lacking usual duodenal histologic changes, which resulted in missed diagnosis for years. Ultimately, crypt epithelial apoptosis, mononuclear inflammation of the lamina propria, and goblet cell loss of intestinal mucosa besides the duodenum clinched the diagnosis of AIE. Colonic histologic abnormalities consistent with AIE in the setting of diarrhea with malnutrition despite duodenal sparing should prompt suspicion for AIE given the pan-enteric nature of this disease.

Varied functions of immune checkpoints during cancer metastasis

Immune checkpoints comprise diverse receptors and ligands including costimulatory and inhibitory molecules, which play monumental roles in regulating the immune system. Immune checkpoints retain key potentials in maintaining the immune system homeostasis and hindering the malignancy development and autoimmunity. The expression of inhibitory immune checkpoints delineates an increase in a plethora of metastatic tumors and the inhibition of these immune checkpoints can be followed by promising results. On the other hand, the stimulation of costimulatory immune checkpoints can restrain the metastasis originating from diverse tumors. From the review above, key findings emerged regarding potential functions of inhibitory and costimulatory immune checkpoints targeting the metastatic cascade and point towards novel potential Achilles’ heels of cancer that might be exploited therapeutically in the future.

Targeting tumors with IL-21 reshapes the tumor microenvironment by proliferating PD-1intTim-3-CD8+ T cells

The lack of sufficient functional tumor-infiltrating lymphocytes in the tumor microenvironment (TME) is one of the primary indications for the poor prognosis of patients with cancer. In this study, we developed an Erbitux-based IL-21 tumor-targeting fusion protein (Erb-IL21) to prolong the half-life and improve the antitumor efficacy of IL-21. Compared with Erb-IL2, Erb-IL21 demonstrated much lower toxicity in vivo. Mechanistically, Erb-IL21 selectively expanded functional cytotoxic T lymphocytes but not dysfunctional CD8+ T cells in the TME. We observed that the IL-21-mediated antitumor effect largely depended on the existing intratumoral CD8+ T cells, instead of newly migrated CD8+ T cells. Furthermore, Erb-IL21 overcame checkpoint blockade resistance in mice with advanced tumors. Our study reveals that Erb-IL21 can target IL-21 to tumors and maximize the antitumor potential of checkpoint blockade by expending a subset of tumor antigen-specific CD8+ T cells to achieve effective tumor control.

Tumor-infiltrating immune cells in hepatocellular carcinoma: Tregs is correlated with poor overall survival

Systematic interrogation of tumor-infiltrating immune cells (TIICs) is key to the prediction of clinical outcome and development of immunotherapies. However, little is known about the TIICs of hepatocellular carcinoma (HCC) and its impact on the prognosis of patients and potential for immunotherapy. We applied CIBERSORT of 1090 tumors to infer the infiltration of 22 subsets of TIICs using gene expression data. Unsupervised clustering analysis by 22 TIICs revealed 4 clusters of tumors, mainly defined by macrophages and T cells, with distinct prognosis and associations with immune checkpoint molecules, including PD-1, CD274, CTLA-4, LAG-3 and IFNG. We found tumors with decreased number of M1 macrophages or increased regulatory T cells were associated with poor prognosis. Based on the multivariate Cox analysis, a nomogram was also established for clinical application. In conclusion, composition of the TIICs in HCC was quite different, which is an important determinant of prognosis with great potential to identify candidates for immunotherapy.

Acute liver injury in the context of immune checkpoint inhibitor-related colitis treated with infliximab

Background

Immune checkpoint inhibitors (ICPIs), used to treat different advanced malignancies, are associated with a wide range of immune-related adverse reactions (irAEs) that deserve close monitoring of patients. Gastrointestinal reactions and hepatotoxicity may occur, which warrant careful evaluation to confirm the etiology and attribution to ICPIs as these events could affect future management.

Case presentation

We describe a case of a patient with prostate adenocarcinoma, treated with dual ICPIs comprised of ipilimumab and nivolumab, who developed elevated liver enzymes in the context of infliximab therapy prescribed to treat gastrointestinal irAE from his ICPIs. The patient’s grade 3 colitis became steroid-refractory, requiring a one-time infusion of infliximab, a biologic agent used commonly in inflammatory bowel disease, as a rescue therapy, to which he responded. The patient subsequently developed liver injury. This presented a diagnostic dilemma involving differential diagnoses of hepatotoxicity due to ICPI or infliximab exposure. A careful review of the clinical history, evaluation of the chronology of events, and exclusion of other causes of acute hepatitis were employed to make the final diagnosis of this event as infliximab-associated hepatotoxicity.

Conclusion

ICPIs such as CTLA-4 and PD-1 inhibitors have the potential to cause both gastrointestinal reactions and hepatotoxicity. An additional confounding factor in our patient’s case was the exposure to infliximab used to manage an established irAE that developed after the last exposure to ICPIs. The clinical history and data supported infliximab-associated hepatotoxicity, rather than an irAE. With the increasing application of ICPIs for different cancers, in conjunction with potential risks for irAE, the liver profile should be closely monitored during treatment with ICPI as well as with anti-TNF-α agents in this patient population.

Combination Immunotherapy Approaches for Pancreatic Cancer Treatment

Pancreatic ductal adenocarcinoma is a lethal malignant disease with a very low medium survival. Currently, metastatic pancreatic cancer poorly responds to conventional treatments and exhibits an acute resistance to most chemotherapy. Few approaches have been shown to be effective for metastatic pancreatic cancer treatment. Novel therapeutic approaches to treat patients with pancreatic adenocarcinoma are in great demand. Last decades, immunotherapies have been evaluated in clinical trials and received great success in many types of cancers. However, it has very limited success in treating pancreatic cancer. As pancreatic cancer poorly responds to many single immunotherapeutic agents, combination immunotherapy was introduced to improve efficacy. The combination therapies hold great promise for enhancing immune responses to achieve better therapeutic effects. This review summarizes the existing and potential combination immunotherapies for the treatment of pancreatic cancer.

Regulatory T-cells promote hepatitis B virus infection and hepatocellular carcinoma progression

Regulatory T-cells (Tregs), known for their immune suppressive function, have been reported in higher numbers, with activated phenotypes and greater potency, in hepatitis B virus (HBV)-related liver diseases than in normal conditions. The numbers, phenotypes, and function of intrahepatic and/or tumor-infiltrating Tregs in HBV-related liver diseases also differ from those of Tregs in the peripheral blood. By inhibiting the function of effector T-cells (Teffs), Tregs play a substantial role in the formation and maintenance of the liver's suppressive microenvironment, which might account for the progression of HBV-related hepatitis and hepatocellular carcinoma (HCC). In acute hepatitis B virus infection, Tregs can safeguard the liver from damage at the cost of prolonged antiviral processes, which results in chronic HBV infection in the liver. Furthermore, Tregs play a role in the development of cirrhosis, the transformation of cirrhosis to HCC, and the progression and metastasis of HCC. Higher levels of Tregs in the peripheral blood and/or tumor sites signify a poorer prognosis in HBV-related liver conditions, and observational data from mouse models and human patients support the theory that depleting Tregs may be therapeutic in HBV-related liver diseases by inducing antiviral and antitumor immunity.

Predictors of tumor-infiltrating lymphocyte efficacy in melanoma

In the past decades, the increasing knowledge in cellular immunology and tumor-host immune interactions, led to the development of immunotherapy approaches. Immunotherapy, based on adoptive cell transfer of ex vivo activated and expanded tumor-infiltrating T lymphocytes (TILs), has shown promising clinical results in patients with metastatic melanoma. TIL therapy yields response rates of around 50% and significant survival benefit in refractory melanoma patients, even after failing other immunotherapies, such as checkpoint inhibitors or cytokine-based therapy. Identifying predictors of TIL efficacy and detection of TIL subsets with specific reactivity against the patient's tumor might be an important milestone toward further improvement of clinical responses and prolonged survival.

When it is not inflammatory bowel disease: differential diagnosis

PURPOSE OF REVIEW

Inflammatory bowel diseases (IBDs) represent a heterogeneous entity whose diagnosis is sometimes difficult to ascertain. Many pathological processes may mimic IBD phenotypes. Among the classical differential diagnoses are enteric infections and infestations as well as drug toxicity. However, recently, more specific differential diagnoses have been included, including monogenic causes of gastrointestinal tract inflammation, particularly in young children. The purpose of the present review is to describe the differential diagnosis of IBD, putting it in a specific clinical and demographic context. This differential diagnosis will be discussed specifically for young children, elderly patients, and immunosuppressed patients.

RECENT FINDINGS

We will focus on the most recent findings and concepts, including monogenic diseases in young children, diverticular disease-associated colitis in elderly patients, and toxic colitis in patients receiving immunosuppressants such as mycophenolate mofetil or biologics such as ipilimumab.

SUMMARY

The aim of this review is to alert the clinician dealing with IBD, concerning a series of specific diagnoses that should be recognized because they may require specific treatment, different from the ones of classical idiopathic IBD.

Systematic Review: Surgery for Patients with Metastatic Melanoma during Active Treatment with Ipilimumab

Studies of ipilimumab have shown improved overall survival in patients with metastatic cutaneous melanoma. As a result, use of ipilimumab in patients with Stage IV melanoma is rapidly increasing. Patients with Stage IV melanoma often require urgent operations for complications from metastases, but little is known about the safety of surgical intervention for patients receiving ipilimumab. We performed a systematic review of the literature using PubMed. Our search terms were melanoma and ipilimumab. We excluded foreign language articles, review articles, and those not addressing cutaneous melanoma. We identified 194 publications matching the search criteria. Only six of those met the inclusion criteria. In these six publications, seven patients who had undergone surgical intervention during treatment with ipilimumab were described. There were no documented surgical complications. We reviewed our institutional experience and identified an additional three patients. No postoperative complications could be attributed directly to ipilimumab. There are limited data on the safety of surgical intervention during treatment with ipilimumab. Preliminary reports suggest there is no reason to withhold or delay surgery for patients receiving ipilimumab therapy.

Ipilimumab-induced acute severe colitis treated by infliximab

Ipilimumab (anti-CTLA-4 antibody) is a new tool for the treatment of metastatic melanoma patients that has led to an improvement in survival rates worldwide. New types of toxicities have been described with ipilimumab called 'immune-related adverse events' or irAEs. Here, we report an acute and steroid resistant case of ipilimumab-induced colitis treated with infliximab in a melanoma stage IV AJCC patient. The patient presented with acute grade 3 diarrhea after the second perfusion of ipilimumab. After the administration of intravenous steroids, the patient continued to have grade 2 diarrhea with erythematous mucous with several ulceration sites on rectosigmoidoscopy. Infliximab perfusion (5 mg/kg) was performed and resulted in resolution of symptoms within 2 days with complete healing was observed by rectal sigmoidoscopy on day 7. After failure of two further lines of chemotherapy, the patient died 10 months after the diagnosis of stage IVM1C melanoma. Treatment algorithms exist for the management of these digestive adverse events; however, some points remain unclear. No predictive marker for the occurrence of this digestive toxicity has been validated to date. Modes of administration of steroids and dosage are not clearly defined, except in cases of acute abdomen; surgery is difficult to propose for patients with a poor prognosis. Infliximab is another option for the treatment of steroid-resistant ipilimumab-induced colitis but its use in metastatic melanoma raises questions of its possible impact on the evolution of cancer. We reviewed at least 19 cases published of infliximab administration for ipilimumab-mediated colitis. Unfortunately, tolerance and cancer evolution have scarcely been reported. Thus, because more patients are being treated with CTLA-4 blockade, management of ipilimumab-induced colitis requires further studies.

PD-1 identifies the patient-specific CD8⁺ tumor-reactive repertoire infiltrating human tumors

Adoptive transfer of tumor-infiltrating lymphocytes (TILs) can mediate regression of metastatic melanoma; however, TILs are a heterogeneous population, and there are no effective markers to specifically identify and select the repertoire of tumor-reactive and mutation-specific CD8⁺ lymphocytes. The lack of biomarkers limits the ability to study these cells and develop strategies to enhance clinical efficacy and extend this therapy to other malignancies. Here, we evaluated unique phenotypic traits of CD8⁺ TILs and TCR β chain (TCRβ) clonotypic frequency in melanoma tumors to identify patient-specific repertoires of tumor-reactive CD8⁺ lymphocytes. In all 6 tumors studied, expression of the inhibitory receptors programmed cell death 1 (PD-1; also known as CD279), lymphocyte-activation gene 3 (LAG-3; also known as CD223), and T cell immunoglobulin and mucin domain 3 (TIM-3) on CD8⁺ TILs identified the autologous tumor-reactive repertoire, including mutated neoantigen-specific CD8⁺ lymphocytes, whereas only a fraction of the tumor-reactive population expressed the costimulatory receptor 4-1BB (also known as CD137). TCRβ deep sequencing revealed oligoclonal expansion of specific TCRβ clonotypes in CD8⁺PD-1⁺ compared with CD8⁺PD-1- TIL populations. Furthermore, the most highly expanded TCRβ clonotypes in the CD8⁺ and the CD8⁺PD-1⁺ populations recognized the autologous tumor and included clonotypes targeting mutated antigens. Thus, in addition to the well-documented negative regulatory role of PD-1 in T cells, our findings demonstrate that PD-1 expression on CD8⁺ TILs also accurately identifies the repertoire of clonally expanded tumor-reactive cells and reveal a dual importance of PD-1 expression in the tumor microenvironment.

Early administration of infliximab for severe ipilimumab-related diarrhea in a critically ill patient

OBJECTIVE

To report a case of ipilimumab-associated life-threatening diarrhea responding quickly to a single dose of infliximab.

CASE SUMMARY

A 67-year-old man presented 3 weeks after his second dose of ipilimumab with severe diarrhea, acute kidney injury, and hypotension. After 2 days of high-dose corticosteroids and supportive care, he continued to have 2.8 L of stool output per day (grade 4 National Cancer Institute Common Terminology Criteria for Adverse Events). The patient was transferred to the medical intensive care unit requiring endotracheal intubation because of concerns of worsening mental status, metabolic acidosis, and increased work of breathing, with a serum bicarbonate concentration of <5 mmol/L. Despite aggressive fluid resuscitation and a sodium bicarbonate infusion, he remained hypotensive and hyponatremic with persistent premature ventricular contractions. On the evening of day 3, infliximab (5 mg/kg) was given, resulting in a rapid decrease in diarrhea. After 48 hours, the acidosis was corrected and electrolytes, renal function, and fluid status were improving. At discharge, diarrhea, acute kidney injury, and acidosis had resolved, and he was discharged on a slow steroid taper.

DISCUSSION

Autoimmune colitis is a described immune-related adverse event of ipilimumab. Prompt recognition, initiation of steroids, and supportive therapy are key to the management of diarrhea. Infliximab should be considered early in steroid-nonresponsive or life-threatening diarrhea.

CONCLUSION

Infliximab is a life-saving intervention in patients with ipilimumab-induced diarrhea.

Ipilimumab-induced colonic perforation

Biologic immune modulators such as ipilimumab have demonstrated the efficacy against metastatic melanoma. We present a recent case of a 52-year-old male who initially developed mild colitis following the initiation of ipilimumab treatment for metastatic melanoma. Despite initial improvement with immediate cessation of drug and initiation of high-dose steroid therapy his clinical condition worsened and the patient presented to our facility in extremis from colonic perforation. Following an extended right hemicolectomy his postoperative period was extended due to continued symptomatic enteritis. After 3 weeks colonoscopy revealed that the autoimmune event had begun to subside;  his condition improved, resulting in discharge. We discuss this particular side effect with respect to ipilimumab adjuvant therapy in melanoma.

Mitigating the toxic effects of anticancer immunotherapy

Advances in our understanding of the regulatory mechanisms of the immune system have led to the development of novel approaches for cancer therapy, including inhibition of immune checkpoints with anti-CTLA-4 and anti-PD-1 antibodies. An increasing number of immunomodulatory treatments are under investigation, and are beginning to show promise in clinical trials. As more-effective therapies become available based on modulation of the immune system in order to trigger or enhance antitumour immune responses, clinicians will need to become familiar with recognizing and controlling the adverse effects arising from immune therapy. This Review describes the toxicity profiles for various anticancer therapies based on the use of agents that block immune checkpoints, immunostimulatory agents, and adoptive T-cell therapy (that is, infusion of modified autologous T cells). The management of patients receiving these treatments presents unique challenges for clinicians. Nevertheless, many of the adverse effects associated with these treatments are reversible and can be managed with supportive care either with or without cessation of therapy. This final point is extremely important given the continued development of new cancer immunotherapies, and the importance of safe and effective use of existing effective FDA-approved agents.

Immune-mediated adverse events associated with ipilimumab ctla-4 blockade therapy: the underlying mechanisms and clinical management

Immunomodulation with the anti-CTLA-4 monoclonal antibody ipilimumab has been shown to extend overall survival (OS) in previously treated and treatment-naive patients with unresectable stage III or IV melanoma. Blockade of CTLA-4 signaling with ipilimumab prolongs T-cell activation and restores T-cell proliferation, thus amplifying T-cell-mediated immunity and the patient's capacity to mount an effective antitumor immune response. While this immunostimulation has unprecedented OS benefits in the melanoma setting, it can also result in immune-mediated effects on various organ systems, leading to immune-related adverse events (irAEs). Ipilimumab-associated irAEs are common and typically low grade and manageable, but can also be serious and life threatening. The skin and gastrointestinal tract are most frequently affected, while hepatic, endocrine, and neurologic events are less common. With proper management, most irAEs resolve within a relatively short time, with a predictable resolution pattern. Prompt and appropriate management of these irAEs is essential and treatment guidelines have been developed to assist oncologists and their teams. Implementation of these irAE management algorithms will help ensure that patients are able to benefit from ipilimumab therapy with adequate control of toxicities.

The price of tumor control: an analysis of rare side effects of anti-CTLA-4 therapy in metastatic melanoma from the ipilimumab network

Background

Ipilimumab, a cytotoxic T-lymphocyte antigen-4 (CTLA-4) blocking antibody, has been approved for the treatment of metastatic melanoma and induces adverse events (AE) in up to 64% of patients. Treatment algorithms for the management of common ipilimumab-induced AEs have lead to a reduction of morbidity, e.g. due to bowel perforations. However, the spectrum of less common AEs is expanding as ipilimumab is increasingly applied. Stringent recognition and management of AEs will reduce drug-induced morbidity and costs, and thus, positively impact the cost-benefit ratio of the drug. To facilitate timely identification and adequate management data on rare AEs were analyzed at 19 skin cancer centers.

Methods and Findings

Patient files (n = 752) were screened for rare ipilimumab-associated AEs. A total of 120 AEs, some of which were life-threatening or even fatal, were reported and summarized by organ system describing the most instructive cases in detail. Previously unreported AEs like drug rash with eosinophilia and systemic symptoms (DRESS), granulomatous inflammation of the central nervous system, and aseptic meningitis, were documented. Obstacles included patientś delay in reporting symptoms and the differentiation of steroid-induced from ipilimumab-induced AEs under steroid treatment. Importantly, response rate was high in this patient population with tumor regression in 30.9% and a tumor control rate of 61.8% in stage IV melanoma patients despite the fact that some patients received only two of four recommended ipilimumab infusions. This suggests that ipilimumab-induced antitumor responses can have an early onset and that severe autoimmune reactions may reflect overtreatment.

Conclusion

The wide spectrum of ipilimumab-induced AEs demands doctor and patient awareness to reduce morbidity and treatment costs and true ipilimumab success is dictated by both objective tumor responses and controlling severe side effects.

CTLA-4 blockade with ipilimumab: long-term follow-up of 177 patients with metastatic melanoma

PURPOSE

Treatment with ipilimumab can cause objective tumor responses in patients with metastatic melanoma. We have treated 177 evaluable patients in three clinical trials and have long-term follow-up to evaluate the durability of responses.

EXPERIMENTAL DESIGN

Patients with metastatic melanoma were treated in three trials from 2002 to 2005. In protocol 1, 56 patients received ipilimumab with gp100 peptides. In protocol 2, 36 patients received ipilimumab with interleukin-2. In protocol 3, 85 patients received ipilimumab with intrapatient dose-escalation and were randomized to receive gp100 peptides. We have analyzed their long-term follow-up and survival data.

RESULTS

With median follow-up for protocols 1, 2, and 3 being 92, 84, and 71 months, median survival was 14, 16, and 13 months with 5-year survival rates being 13%, 25%, and 23%, respectively. Patients in protocol 2 had a 17% complete response (CR) rate, compared with 7% in protocol 1 and 6% in protocol 3. These CR rates are higher than previously reported for the same trials because some patients who eventually became complete responders had continual tumor regression months to years after therapy. All but one of the 15 complete responders are ongoing at 54+ to 99+ months.

CONCLUSIONS

This report provides the longest follow-up of patients with melanoma treated with ipilimumab and shows that ipilimumab can induce durable, potentially curative tumor regression in a small percentage of patients with metastatic melanoma. The combination of ipilimumab and interleukin-2 seems to have an increased CR rate, but this needs to be tested in a randomized trial.

Regulatory T cell: a protection for tumour cells

Characterized by immunosuppression regulatory T cells (Tregs) play a key role in maintaining immune tolerance. A growing number of tumours have been found with Tregs accumulating in microenvironment and patients with high density of Tregs in tumour stroma get a worse prognosis, which suggests that Tregs may inhibit anti-tumour immunity in stroma, resulting in a poor prognosis. In this paper, we demonstrate the accumulation of Tregs in tumour stroma and the possible suppressive mechanisms. We also state the immunotherapy that has being used in animal and clinical trials.

Novel treatments for metastatic cutaneous melanoma and the management of emergent toxicities

The last 12 months have seen the beginning of a new era in the treatment options available for patients with metastatic cutaneous melanoma, a disease previously characterised by its poor prognosis and limited treatment options. Two mechanistically diverse agents have now demonstrated an overall survival benefit in different patient subgroups and further clinical trials are ongoing with emerging single agents and novel combinations. The first agent to demonstrate an overall survival benefit was the CTLA-4 antibody, ipilimumab, illustrating the importance of the immune system and immunomodulation in melanoma tumorigenesis. The second group of agents to show a survival benefit were the selective BRAF inhibitors, vemurafenib and GSK2118436, in patients who are BRAF V600 mutation positive. In addition, in the same BRAF mutant patient population, MEK inhibitors also show promising results and are currently under investigation in later stage trials. Although ipilimumab, BRAF and MEK inhibitors are just passing through the clinical trials arena, their use will rapidly become more widespread. Along with their significant clinical benefits, there are also unique adverse events related to these agents. Although the majority are mild and can be managed with supportive treatment, some toxicities require special management strategies. We outline up-to-date clinical development and management guidelines for ipilimumab, as well as the BRAF and MEK inhibitors.

Current and planned multicenter trials for patients with primary or metastatic melanoma

Multicenter clinical trials have established new standards of care in the surgical and medical management of malignant melanoma. They have led to the testing of new therapies and improved outcomes for patients with loco-regional and distant disease. Many pressing questions remain, however, and additional multicenter trials are currently underway to address them. The purpose of this review is to summarize relevant ongoing and planned multicenter trials that have and continue to define current melanoma management.

Immunotherapy for metastatic solid cancers

After decades of research on solid tumor immunology, immunotherapy has shown effectiveness in patients with metastatic solid cancers. Immune modulators such as IL-2 and anti-CTLA-4 can mediate tumor regression in patients with metastatic melanoma and renal cancer, two tumor types that appear exceptional in their ability to spontaneously harbor endogenous antitumor immune cells. The responses can be long lasting, but the number of patients who benefit from these molecules remains limited. Combinations of these agents with cytotoxic and biologic agents are being investigated as a means to increase response rates and in an attempt to broaden application to other cancer types. Rare responses to cancer vaccines suggest that a better understanding of the underlying biology and mechanism of actions may lead to wider application in the future. The most effective form of immunotherapy thus far, capable of eradicating large tumor burdens in melanoma patients, is the ACT of TIL given to patients after lymphodepletion. As an alternative, lymphocytes engineered to recognize tumor-associated antigens can be safely infused to patients. With this approach, tumor regression is now being reported for cancers other than melanoma, but success remains constrained by the identification of antigens expressed with high specificity by cancer cells and not by normal tissues.

Braking bad: blockade of inhibitory pathways improves interleukin-15 therapy

Blockade of the CTLA-4 and PD-1 inhibitory pathways in T cells via the administration of neutralizing antibodies at the time of interleukin (IL)-15 therapy markedly enhanced the survival of tumor-bearing mice as compared with those receiving IL-15 alone or IL-15 in combination with just one of the antibodies.

Vaccines and immunotherapeutics for the treatment of malignant disease

The employment of the immune system to treat malignant disease represents an active area of biomedical research. The specificity of the immune response and potential for establishing long-term tumor immunity compels researchers to continue investigations into immunotherapeutic approaches for cancer. A number of immunotherapeutic strategies have arisen for the treatment of malignant disease, including various vaccination schemes, cytokine therapy, adoptive cellular therapy, and monoclonal antibody therapy. This paper describes each of these strategies and discusses some of the associated successes and limitations. Emphasis is placed on the integration of techniques to promote optimal scenarios for eliminating cancer.

Sentinel lymph node biopsy for melanoma: indications and rationale

BACKGROUND

The disease status of regional lymph nodes is the most important prognostic indicator for patients with melanoma. Sentinel lymph node biopsy (SLNB) was developed as a technique to surgically assess the regional lymph nodes and spare node-negative patients unnecessary and potentially morbid complete lymphadenectomies.

METHODS

We reviewed the literature on SLNB for cutaneous melanoma to provide insight into the rationale for the current widespread use of SLNB.

RESULTS

Multiple studies show that the status of the SLN is an important prognostic indicator. Those with positive SLNs have significantly decreased disease-free and melanoma-specific survival compared with those who have negative SLNs. In the Multicenter Selective Lymphadenectomy Trial I (MSLT-I), in which patients with intermediate-thickness melanoma were randomized to SLNB (and immediate completion lymphadenectomy if the SLN was positive) vs observation (and a lymphadenectomy only after presenting with clinically evident recurrence), the 5-year survival rate was 72.3% for patients with positive sentinel nodes and 90.2% for those with negative sentinel nodes (P < .001). Although overall survival was not increased in patients who underwent SLNB compared with those who were randomized to observation, patients who underwent SLNB had a significantly increased 5-year disease-free survival rate compared with those who underwent observation alone (78.3% in the biopsy group and 73.1% in the observation group; P = .009). For those with nodal metastases, patients who underwent SLNB and immediate lymphadenectomy had an increased overall 5-year survival rate compared with those who had lymphadenectomy only after presenting with clinically evident disease (72.3% vs 52.4%; P = .004). Moreover, other studies show that for patients with thin melanomas <or= 1.0 mm, the overall survival rate is significantly worse for those with positive SLNs compared to those with negative SLNs. For thin melanomas, Breslow depth >or= 0.76 mm and increased mitotic rate have been shown to be associated with an increased incidence of SLN metastases.

CONCLUSIONS

SLNB provides important prognostic and staging data with minimal morbidity and can be used to identify regional node-negative patients who would not benefit from a complete nodal dissection. In our opinion, SLNB should be performed on most patients (with acceptable surgical and anesthesia risk) who have melanomas with a Breslow depth >or= 0.76 mm.

T-regulatory cell modulation: the future of cancer immunotherapy?

T-regulatory cells suppress anti-tumour immunity in cancer patients and in murine tumour models. Furthermore, their activity is likely to have an effect on the effectiveness of immunotherapeutic treatments for cancer. Here we describe the current status of developing clinical strategies for modulating Treg activity in cancer patients.

Monoclonal antibodies in the treatment of pancreatic cancer

Human pancreatic cancer is a malignant disease with almost equal incidence and mortality. Effective diagnostic and therapeutic strategies are still urgently needed to improve its survival rate. With advances in structural and functional genomics, recent work has focused on targeted molecular therapy using monoclonal antibodies. This review summarizes the target molecules on the tumor cell surface and normal tissue stroma, which are related to pancreatic cancer oncogenesis, tumor growth or resistance to chemotherapy, as well as molecules involved in regulating inflammation and host immunoresponses. Targeted molecules include cell-surface receptors, such as the EGF receptor, HER2, death receptor 5 and IGF-1 receptor. Effects of monoclonal antibodies against these target molecules alone or in combination with chemotherapy, small-molecule signal transduction inhibitors, or radiation therapy are also discussed. Also discussed are the use of toxin or radioisotope conjugates, and information relating to the use of these targeting agents in pancreatic cancer clinical trials. Although targeted molecular therapy with monoclonal antibodies has made some progress in pancreatic cancer treatment, especially in preclinical studies, its clinical application to improve the survival rate of pancreatic cancer patients requires further investigation.