Tumor Regression and Allograft Rejection after Administration of Anti-PD-1

Immunotherapy for Non-melanoma Skin Cancer

Purpose of Review

The therapeutic landscape for non-melanoma skin cancer (NMSC) has recently expanded with the development of effective and targeted immunotherapy. Here, we provide an overview of the role of immunotherapy in the management of advanced cutaneous carcinomas.

Recent Findings

Several agents were recently U.S. Food and Drug Administration (FDA)-approved for the treatment of locally advanced and metastatic cutaneous squamous cell carcinoma, Merkel cell carcinoma, and basal cell carcinoma. However, recent approvals in tissue-agnostic indications may also benefit other NMSCs including cutaneous adnexal solid tumors with high tumor mutation burdens or microsatellite instability. Furthermore, while FDA-approved indications will likely continue to expand, continued studies are needed to support the role of immunotherapy in the neoadjuvant, adjuvant, and refractory settings.

Summary

Immunotherapy is emerging as the standard of care for several advanced NMSCs not amenable to surgery and radiation. Ongoing evaluation of the clinical trial landscape is needed to optimize enrollment and ensure continued innovation.

The Correlation Between Immunohistochemistry Findings and Metastasis in Squamous Cell Carcinoma: A Review

BACKGROUND

Cutaneous squamous cell carcinoma (SCC) is the second most common type of skin cancer. Only 2% to 5% of SCCs metastasize; however, those do carry a poor prognosis. Immunohistochemistry (IHC) is widely used by pathologists to characterize skin cancers and provide clinically useful information.

OBJECTIVE

To evaluate the potential prognostic associations between IHC findings and metastasis in SCC.

METHODS

Searches were conducted in MEDLINE via PubMed for articles published between 1999 and 2019. Search criteria included key words "immunohistochemistry" and "cutaneous squamous cell carcinoma." Six hundred and fifty-three articles were returned and screened, which ultimately left 31 for inclusion in our manuscript.

RESULTS

Thirty-one articles analyzed in this review included a discussion of the expression of a particular IHC marker and the associated risk of metastasis and/or clinical utility of IHC markers in SCC, especially metastatic SCC. Markers that had several or more studies supporting clinical utility were E-cadherin, podoplanin, CD8+ T cells, PD-L1, epidermal growth factor receptor, and Cyclin D1.

CONCLUSION

Immunohistochemistry profiling of SCC may be useful in select cases when providing a prognosis remains challenging and in identification of potential therapeutic targets for high-risk or metastatic tumors.

Bilateral Corneal Graft Rejection Associated With Pembrolizumab Treatment

PURPOSE

To report the first case of corneal graft rejection presumably associated with pembrolizumab immunotherapy.

METHODS

Case report and literature review.

RESULTS

An asymptomatic 85-year-old woman with a history of bilateral penetrating keratoplasty presented for a follow-up visit with bilateral diffuse keratic precipitates and subepithelial infiltrates. There were no anterior chamber cells. Bilateral subclinical corneal graft rejection was suspected. Three months previously, pembrolizumab immunotherapy was started for a metastatic urothelial cell tumor. Corneal graft rejection was managed with topical dexamethasone drops, which were tapered slowly. Pembrolizumab treatment was continued with careful ophthalmological follow-up. Unfortunately, recurrence of corneal graft rejection was observed 8 weeks after cessation of topical dexamethasone drops. After consulting the treating oncologist, pembrolizumab treatment was stopped to prevent recurrent corneal graft rejection.

CONCLUSIONS

We report the first case of corneal graft rejection presumably associated with pembrolizumab immunotherapy. Corneal graft rejection may be successfully managed with corticosteroid therapy. However, constant vigilance and follow-up are advised because of the risk of recurrence in case of continued pembrolizumab treatment. Given the subclinical presentation, baseline ophthalmological screening is advised in all corneal graft patients after initiating immune checkpoint inhibitor therapy.

Successful Treatment of In-Transit Metastatic Melanoma in a Renal Transplant Patient With Combination T-VEC/Imiquimod Immunotherapy

In the era of immunotherapy for cancer, solid organ transplant patients who go on to develop metastatic or locally advanced melanoma offer particularly difficult challenges. New approaches are needed for these patients. We present a case of in-transit metastatic melanoma in a renal transplant patient. The patient was initially managed with talimogene laherparepvec (T-VEC) injections alone with continued local progression. Addition of topical imiquimod 5% cream to intralesional T-VEC resulted in a rapid and dramatic response, with complete clearance of the cutaneous in-transit metastases and without any sign of organ rejection. In solid organ transplant patients who lack surgical options and are not eligible for treatment with a BRAF inhibitor, and for whom treatment with checkpoint inhibitors present risk of organ rejection, T-VEC either alone or in combination with topical imiquimod should be considered for patients with locally advanced disease. This combination should be a consideration, with close observation, in patients with a history of organ transplantation and immunosuppression.

The Outcomes of Systemic Treatment in Recurrent Hepatocellular Carcinomas Following Liver Transplants

BACKGROUND

Treatment of hepatocellular carcinoma (HCC) recurrences following liver transplant (LT) is challenging. Most clinical trials of systemic therapies for advanced HCC excluded patients with any history of organ transplant. We aimed to assess the outcomes in using various systemic therapies in patients with post-LT recurrence.

METHODS

Consecutive patients with HCC and recurrences following LT at a large tertiary centre from 2005 to 2018 were reviewed. Overall survival (OS), response rates and adverse events (AEs) were analysed.

RESULTS

Forty-three consecutive patients with a recurrence of HCC following LT were identified from 2005 to 2018. Median OS from diagnosis of recurrence was 17 months (CI 11.3, 22.7). Early recurrence within 12 months of transplant was associated with a significantly worse median survival of 10 months (CI 8.5, 11.4) compared to 26 months (CI 18.8, 33.2) when recurrences occurred after 12 months from transplant (p < 0.001) with a hazard ratio of 0.104 (log-rank test, p < 0.001). A total of 41 patients had received systemic therapies and 79.1% of them were on sorafenib as the first-line treatment. Among these patients treated with sorafenib, median OS from recurrence was 14 months (CI 7.3, 20.7). Hand-foot syndrome (34.7%) was most common among AEs followed by diarrhoea (26.7%). Overall, AEs led to dose interruptions in 8.8% of patients. Notably, 47.1% of patients received subsequent lines of systemic therapies after sorafenib.

CONCLUSIONS

Early recurrence within 1 year from transplant was the most significant risk factor. Treatment efficacy and adverse events and tolerability of sorafenib were comparable with those in the setting of advanced HCC without transplant.

High numbers of programmed cell death-1-positive tumor infiltrating lymphocytes correlate with early onset of post-transplant lymphoproliferative disorder

Post-transplant lymphoproliferative disorder (PTLD) is a life-threatening complication of transplantation. In addition to reactivation of Epstein-Barr virus in immunocompromised patients, impaired tumor immunity is suggested to be a risk factor for PTLD. However, it remains unclear whether immune suppressive tumor-infiltrating lymphocytes (TILs) correlate with the occurrence or prognosis of PTLD. We analyzed TILs in 26 patients with PTLD to elucidate the clinicopathological significance of the expression of PD-1 and FoxP3, which are associated with exhausted T-cells and regulatory T-cells (Tregs), respectively. Numbers of PD-1⁺ TILs in the PTLD specimens were significantly higher in patients who developed PTLD early after transplantation (P = 0.0040), while numbers of FoxP3⁺ TILs were not (P = 0.184). There was no difference in overall response rate regardless of the expression of PD-1 or FoxP3. FoxP3^high patients tended to have a shorter time to progression compared with FoxP3^low patients, especially in the case of FoxP3^high patients with diffuse large B-cell lymphoma-subtype PTLD (P = 0.011), while PD-1^high patients did not. These results suggest that T-cell exhaustion may be mainly associated with PTLD development, while immune suppression by Tregs may be dominant in enhanced progression of PTLD following disease occurrence.

High-Risk Cutaneous Squamous Cell Carcinoma of the Head and Neck: A Clinical Review

BACKGROUND

Given the rapidly evolving nature of the field, the current state of "high-risk" head and neck cutaneous squamous cell carcinoma (HNcSCC) is poorly characterized.

METHODS

Narrative review of the epidemiology, diagnosis, workup, risk stratification, staging and treatment of high-risk HNcSCC.

RESULTS

Clinical and pathologic risk factors for adverse HNcSCC outcomes are nuanced (e.g., immunosuppression and perineural invasion). Frequent changes in adverse prognosticators have outpaced population-based registries and the variables they track, restricting our understanding of the epidemiology of HNcSCC and inhibiting control of the disease. Current heterogeneous staging and risk stratification systems are largely derived from institutional data, compromising their external validity. In the absence of staging system consensus, tumor designations such as "high risk" and "advanced" are variably used and insufficiently precise to guide management. Evidence guiding treatment of high-risk HNcSCC with curative intent is also suboptimal. For patients with incurable disease, an array of trials are evaluating the impact of immunotherapy, targeted biologic therapy, and other novel agents.

CONCLUSION

Population-based registries that broadly track updated, nuanced, adverse clinicopathologic risk factors, and outcomes are needed to guide development of improved staging systems. Design and development of randomized controlled trials (RCTs) in advanced-stage HNcSCC populations are needed to evaluate (1) observation, sentinel lymph node biopsy, or elective neck dissection for management of the cN0 neck, (2) indications for surgery plus adjuvant radiation versus adjuvant chemoradiation, and (3) the role of immunotherapy in treatment with curative intent. Considering these knowledge gaps, the authors explore a potential high-risk HNcSCC treatment framework.

Application of Immune Checkpoint Inhibitors in Solid Organ Transplantation Recipients: A Systematic Review

BACKGROUND

Solid organ transplantation (SOT) is a treatment method for end-stage organ diseases and improve their life quality, while using long-term immunosuppressant drugs (ISD) is needed to suppress the function of the immune system. Immune checkpoint inhibitors (ICIs) are a class of anti-tumor drugs that kill tumors by activating the autoimmune system. The primary objective of our systematic review is to investigate the risk factors for organ rejection and the efficacy of ICIs in solid organ transplantation recipients (SOTRs).

METHODS

We searched four databases to find relevant articles up to January 2021. A total of 61 articles involving 106 SOTRs met the screening criteria and were included in our systematic review. The collected data were statistical described, and the risk factors were analyzed by logistic regression.

RESULTS

Forty-four patients (41.5%) developed host-versus-graft response (HVGR) after ICIs. mTOR inhibitors (pre-ICIs) (p = 0.069, OR = 0.377, 95% CI 0.132-1.078) and calcineurin inhibitors (post-ICIs) (p = 0.056, OR = 0.375, 95%CI 0.137-1.025) may help reduce the incidence of HVGR. Hormones (pre-ICIs) (p = 0.026, OR = 3.150, 95%CI 1.150-8.628) and anti-metabolites (pre-ICIs) (p = 0.022, OR = 3.214, 95%CI 1.185-8.720) may adversely affect the efficacy of ICIs. Only 35.6% of patients both responded well to ICIs treatment and did not develop HVGR.

CONCLUSIONS

Our systematic review summarizes the use of ICIs in SOTRs and evaluates the efficacy of ICIs and the risk factors that induce HVGR. Through risk factor analysis, we found that mTOR inhibitors and calcineurin inhibitors may help to reduce the occurrence of HVGR; hormones and anti-metabolic drugs may have adverse effects on the efficacy of ICIs. In addition, there is a contradictory relationship between the occurrence of HVGR and the efficacy of ICIs.

Changes in cancer incidence and outcomes among kidney transplant recipients in the United States over a thirty-year period

Recipients of kidney transplants have elevated cancer risk compared with the general population. Improvements over time in transplant care and cancer treatment may have affected incidence and outcomes of cancer among recipients of kidney transplant. To evaluate this, we used linked United States transplant and cancer registry data to study 101,014 adult recipients of kidney transplants over three decades (1987-1996, 1997-2006, 2007-2016). Poisson regression was used to assess trends in incidence for cancer overall and seven common cancers. Associations of cancer with risk of death-censored graft failure (DCGF) and death with functioning graft (DWFG) were evaluated with Cox regression. We also estimated absolute risks of DCGF and graft failure following cancer for recipients transplanted in 2007-2016. There was no significant change in the incidence of cancer overall or for six common cancers in recipients across the 1987-2016 period. Only the incidence of prostate cancer significantly decreased across this period after multivariate adjustment. Among recipients of kidney transplants with non-Hodgkin lymphoma, there were significant declines over time in elevated risks for DCGF and DWFG but no significant changes for other combined cancers. For recipients transplanted in the most recent period (2007-2016), risks following cancer diagnosis remained high, with 38% experiencing DWFG and 14% graft failure within four years of diagnosis. Absolute risk of DWFG was especially high following lung cancer (78%), non-Hodgkin lymphoma (38%), melanoma (35%), and colorectal cancer (49%). Thus, across a 30-year period in the United States, there was no overall change in cancer incidence among recipients of kidney transplants. Despite improvements for non-Hodgkin lymphoma, cancer remains a major cause of morbidity and mortality.

Nivolumab for Metastatic Urothelial Cancer in a Renal Allograft Recipient With Subsequent Graft Rejection and Treatment Complete Remission: A Case Report

Immune checkpoint inhibitors (ICIs) expanded the therapeutic options for several cancers. However, whether some special groups of patients including those with organ transplantation can receive ICIs remains unclear. In this report we presented an interesting case. A 54-year-old woman underwent kidney transplantation, developed metastasis 7 years after operation of the bladder tumor. Her disease progressed after chemotherapy and radiotherapy. Anti-PD-1 immunotherapy was then considered. After two cycles of nivolumab immunotherapy, the patient’s renal function declined rapidly. Acute allograft rejection was considered. There was no significant decrease in creatinine after glucocorticoid pulse therapy. Third course of nivolumab was given, and regularly hemodialysis was simultaneously conducted. Two weeks later, the patient showed left abdominal pain. CT scan revealed a reduction in tumor burden, while enlarged volume of kidney graft. Immunotherapy stopped. Two months after the third course, CT demonstrated a complete remission to immunotherapy. 23 months after the third course, CT showed that the swelling transplanted kidney was smaller than previous, and no recurrence was observed.

Reconsidering Dexamethasone for Antiemesis when Combining Chemotherapy and Immunotherapy

Whether the immune suppressive action of glucocorticoid steroids, such as dexamethasone, might reduce the benefits of cancer immunotherapy has long been a concern. Observations that established tumor regressions in response to immune checkpoint inhibitors (ICIs) often persist, despite the use of steroids to mitigate ICI-related autoimmune breakthrough, are not sufficiently reassuring, because these observations do not address the potential blunting of immune priming at the initiation of ICI therapy. With increasing indications for ICI in combination with chemotherapy, this issue merits reconsideration. Professional society guidance advises that dexamethasone should be used as first-line prophylaxis for nausea and vomiting in patients receiving ICI and highly emetogenic chemotherapy combination regimens. Here, we review the availability of data on this subject and propose an alternative approach focused on the adoption of steroid minimization or sparing for prophylaxis of nausea until the underlying immune biology is better understood.

Cutaneous Squamous Cell Carcinoma in the Age of Immunotherapy

Cutaneous squamous cell carcinoma (cSCC) is the second most prevalent skin cancer globally. Because most cSCC cases are manageable by local excision/radiotherapy and hardly become life-threatening, they are often excluded from cancer registries in most countries. Compared with cutaneous melanoma that originates from the melanin-producing, neural crest-derived epidermal resident, keratinocyte (KC)-derived cancers are influenced by the immune system with regards to their pathogenetic behaviour. Congenital or acquired immunosurveillance impairments compromise tumoricidal activity and raises cSCC incidence rates. Intriguingly, expanded applications of programmed death-1 (PD-1) blockade therapies have revealed cSCC to be one of the most amenable targets, particularly when compared with the mucosal counterparts arisen in the esophagus or the cervix. The clinical observation reminds us that cutaneous tissue has a peculiarly high immunogenicity that can evoke tumoricidal recall responses topically. Here we attempt to redefine cSCC biology and review current knowledge about cSCC from multiple viewpoints that involve epidemiology, clinicopathology, molecular genetics, molecular immunology, and developmental biology. This synthesis not only underscores the primal importance of the immune system, rather than just a mere accumulation of ultraviolet-induced mutations but also reinforces the following hypothesis: PD-1 blockade effectively restores the immunity specially allowed to exist within the fully cornified squamous epithelium, that is, the epidermis.

Utility of Serial Donor-derived Cell-free DNA Measurements for Detecting Allograft Rejection in a Kidney Transplant Recipient After PD-1 Checkpoint Inhibitor Administration

Background.

Donor-derived cell-free DNA (dd-cfDNA) is a useful biomarker of rejection that originates from allograft cells undergoing injury. Plasma levels <1% in kidney transplant recipients have a high negative predictive value for active allograft rejection. The utility of this biomarker in kidney transplant recipients receiving immune checkpoint inhibitor therapy is unknown.

Methods.

We describe a case in which serial dd-cfDNA monitoring facilitated the use of immune checkpoint inhibitor therapy, which is known to be associated with high rates of rejection, in a kidney transplant recipient with metastatic cancer.

Results.

A 72-y-old man with end-stage kidney disease secondary to autosomal dominant polycystic kidney disease underwent living unrelated kidney transplant in December 2010. His immunosuppression regimen included tacrolimus, mycophenolate, and prednisone. In July 2017, he presented with metastatic cutaneous squamous cell carcinoma. After his disease progressed through radiation therapy and cetuximab, he received pembrolizumab (antiprogrammed cell death protein 1). His dd-cfDNA level was undetectable at baseline, then increased during treatment but remained <1%. This trend, despite fluctuations in serum creatinine levels during therapy, allowed for continuation of pembrolizumab and successful treatment of his metastatic cancer without clinically evident allograft rejection. After discontinuation of pembrolizumab, dd-cfDNA levels fell below the level of detection. Genetic analysis of the cutaneous squamous cell carcinoma demonstrated a genetic profile distinct from the dd-cfDNA, indicating that tumor lysis did not impact increases in dd-cfDNA.

Conclusions.

Serial dd-cfDNA measurements may provide a useful, noninvasive biomarker for detecting allograft injury that may facilitate the use of immunomodulatory therapies in organ transplant recipients with cancer.

Safe Administration of Cemiplimab to a Kidney Transplant Patient with Locally Advanced Squamous Cell Carcinoma of the Scalp

Immunotherapies directed at T-cell activation through antibodies targeting checkpoint proteins, such as programmed cell death 1 (PD1), are rapidly becoming the new standard of care in the treatment of several malignancies. Cemiplimab is a monoclonal antibody targeting PD1 that has recently emerged as a highly active treatment for locally advanced and metastatic cutaneous squamous cell carcinoma (CSCC). Patients who have received an organ transplant (OTRs) have been traditionally excluded from clinical trials with checkpoint inhibitors (CIs), given concerns for organ rejection. Renal transplant recipients (RTRs) are more likely to develop cancers than the general population, and skin cancers are among the most frequent malignancies. We report the case of a 72-year-old man with a history of a kidney transplant who presented with a rapidly growing, locally advanced squamous cell carcinoma (SCC) of the scalp that recurred within four weeks from surgical resection. The patient was able to safely receive ten cycles of cemiplimab so far with significant clinical benefit, and no issues with his kidney function, while continuing immunosuppression with low dose prednisone alone. An ongoing clinical trial (NCT04339062) is further exploring the safety of CIs in patients with metastatic CSCC who have previously received allogeneic hematopoietic stem cell transplant or a kidney transplant.

Association of Immunosuppression With Outcomes of Patients With Cutaneous Squamous Cell Carcinoma of the Head and Neck

Importance

Patients with immunosuppression have a higher incidence of cutaneous squamous cell carcinoma (cSCC) and often present with more aggressive, multifocal disease.

Objectives

To determine the risks for mortality in patients with cSCC and immunosuppression compared with nonimmunosuppression and to compare the difference in mortality risk based on the cause of immunocompromise.

Design, Setting, and Participants

This retrospective cohort study of patients with cSCC of the head and neck recruited participants from a tertiary cancer care center. Patients who underwent no treatment, wide local excision, or biopsy of the lesions were eligible for inclusion from January 1, 1995, to September 30, 2015. Data were analyzed from March 21, 2018, to April 4, 2019.

Exposures

Immunocompromise, defined as having solid organ transplant, stem cell transplant, hematopoetic malignant disease, autoimmune disease requiring treatment with immunosuppressive therapy, type 1 or 2 diabetes treated with insulin, HIV or AIDS, or other hematoproliferative disorder.

Main Outcomes and Measures

Patients were divided into 2 groups according to their immune status (immunosuppression vs no immunosuppression). The primary outcome measure was disease-specific survival. A Cox proportional hazards regression model was used to determine the association of immune status with disease outcome.

Results

A total of 796 patients (680 men [85.4%]; median age, 69 [range, 27-98] years), including 147 with and 649 without immunosuppression (IS and non-IS groups, respectively), constituted the final cohort. In the IS group, 77 (52.4%) had diabetes, 39 (26.5%) had lymphoma or leukemia, 25 (17.0%) had an organ or stem cell transplant, and 3 (2.0%) had HIV. Five-year disease-specific survival was 68.2% in the IS group compared with 84.1% in the non-IS group (difference, 15.9%; 95% CI, 3.5%-27.4%). Immunosuppression was independently associated with worse disease-specific survival (hazard ratio, 2.32; 95% CI, 1.53-3.50).

Conclusions and Relevance

This study's findings suggest that immunosuppression is independently associated with a worse outcome in cSCC, with a 2.32 times increased risk of disease-specific death after adjusting for age, history of skin cancer, recurrent or persistent disease status, disease stage, and treatment.

Immune Checkpoint Inhibitors in Transplantation-A Case Series and Comprehensive Review of Current Knowledge

Cancer is a leading cause of morbidity and deaths in solid organ transplant recipients. In immunocompetent patients, cancer prognosis has been dramatically improved with the development of immune checkpoint inhibitors (ICI), as programmed cell death protein 1/programmed death-ligand 1 and cytotoxic T lymphocyte-associated antigen 4 inhibitors, that increase antitumor immune responses. ICI has been developed outside of the scope of transplantation because of the theoretical risk of graft rejection, which has later been confirmed by the publication of several cases and small series. The use of ICI became unavoidable for treating advanced cancers including in organ transplant patients, but their management in this setting remains highly challenging, as to date no strategy to adapt the immunosuppression and to prevent graft rejection has been defined. In this article, we report a monocentric series of 5 solid organ transplant recipients treated with ICI and provide a comprehensive review of current knowledge of ICI management in the setting of solid organ transplantation. Strategies warranted to increase knowledge through collecting more exhaustive data are also discussed.

A multi-center study on safety and efficacy of immune checkpoint inhibitors in cancer patients with kidney transplant

Immune checkpoint inhibitors (ICIs) are widely used for various malignancies. However, their safety and efficacy in patients with a kidney transplant have not been defined. To delineate this, we conducted a multicenter retrospective study of 69 patients with a kidney transplant receiving ICIs between January 2010 and May 2020. For safety, we assessed the incidence, timing, and risk factors of acute graft rejection. For efficacy, objective response rate and overall survival were assessed in cutaneous squamous cell carcinoma and melanoma, the most common cancers in our cohort, and compared with stage-matched 23 patients with squamous cell carcinoma and 14 with melanoma with a kidney transplant not receiving ICIs. Following ICI treatment, 29 out of 69 (42%) patients developed acute rejection, 19 of whom lost their allograft, compared with an acute rejection rate of 5.4% in the non-ICI cohort. Median time from ICI initiation to rejection was 24 days. Factors associated with a lower risk of rejection were mTOR inhibitor use (odds ratio 0.26; 95% confidence interval, 0.09-0.72) and triple-agent immunosuppression (0.67, 0.48-0.92). The objective response ratio was 36.4% and 40% in the squamous cell carcinoma and melanoma subgroups, respectively. In the squamous cell carcinoma subgroup, overall survival was significantly longer in patients treated with ICIs (median overall survival 19.8 months vs. 10.6 months), whereas in the melanoma subgroup, overall survival did not differ between groups. Thus, ICIs were associated with a high risk of rejection in patients with kidney transplants but may lead to improved cancer outcomes. Prospective studies are needed to determine optimal immunosuppression strategies to improve patient outcomes.

Toxicities from immunotherapy: From clinical trials to real-world clinical practice

In recent years, immunotherapy has become an important pillar of cancer treatment, with high response rates regardless of tumour histology or baseline mutations. However, immune activation associated with check-point inhibitors is not selective and a large variety of immune-related adverse events have been associated with anti-PD1, anti-PD-1/L-1 and anti-CTLA-4 agents. Though diagnosis and treatment of these toxicities have been established according to the recommendations from clinical trials and in line with the autoimmune disorders that they mimic, increasing real-world data is coming up showing that these adverse events may have differential characteristics and management, especially in terms of the use of corticoids, second-line treatments, salvage therapy for life-threatening cases and reintroduction of immunotherapy. Herein we present a comprehensive review of current recommendations and real-world data on the main immune-related adverse events of immunotherapy.

Immune Checkpoint Blockade in Advanced Cutaneous Squamous Cell Carcinoma: What Do We Currently Know in 2020?

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer that predominantly arises in chronically sun-damaged skin. Immunosuppression, genetic disorders such as xeroderma pigmentosum (XP), exposure to certain drugs and environmental noxae have been identified as major risk factors. Surgical removal of cSCC is the therapy of choice and mostly curative in early stages. However, a minority of patients develop locally advanced tumors or distant metastases that are still challenging to treat. Immune checkpoint blockade (ICB) targeting CTLA-4, PD-L1 and PD-1 has tremendously changed the field of oncological therapy and especially the treatment of skin cancers as tumors with a high mutational burden. In this review, we focus on the differences between cSCC and cutaneous melanoma (CM) and their implications on therapy, summarize the current evidence on ICB for the treatment of advanced cSCC and discuss the chances and pitfalls of this therapy option for this cancer entity. Furthermore, we focus on special subgroups of interest such as organ transplant recipients, patients with hematologic malignancies, XP and field cancerization.

Solid organ transplantation worsens the prognosis of patients with cutaneous squamous cell carcinoma of the head and neck region-Comparison between solid organ transplant recipients and immunocompetent patients

BACKGROUND

Cutaneous squamous cell carcinoma of the head and neck (CSCC-HN) appears to behave more aggressively in immunosuppressed patients. We aimed to investigate this hypothesis by comparing solid organ transplant recipients (SOTR) with CSCC-HN to immunocompetent patients.

METHODS

A retrospective comparative study was conducted for SOTR and immunocompetent patients who were treated for CSCC-HN.

RESULTS

A total of 177 SOTR and 157 immunocompetent patients with CSCC-HN were included. Lymph node metastases were more common in the SOTR group (9% vs 3%), and distant metastases occurred only in SOTR (3% of patients). SOTR had a higher rate of recurrences (19% vs 10%), which were mostly regional (7%) and distant (3%). The 2-year disease-specific survival of SOTR was lower (93% vs 100%).

CONCLUSIONS

SOTR with CSCC-HN has significantly worse outcomes compared to immunocompetent patients. Solid-organ transplantation should be regarded as a negative prognostic factor in patients with CSCC-HN.

Safety and Efficacy of Immune Checkpoint Inhibitors for Patients With Metastatic Urothelial Carcinoma and End-Stage Renal Disease: Experiences From Real-World Practice

BACKGROUND

Immune checkpoint inhibitors (ICIs) are used widely for treating metastatic urothelial carcinoma (mUC). In practical settings, evidence is lacking on the efficacy of ICIs in some difficult-to-treat patients, such as those with end-stage renal disease (ESRD). Herein, we evaluate the safety and efficacy of ICIs for patients with mUC and ESRD.

METHODS

For this retrospective study, patients with mUC who were given ICIs at Kaohsiung Chang Gang Memorial Hospital and Linkou Chang Gung Memorial Hospital between April 2016 and November 2019 were consecutively enrolled. All clinicopathologic data, treatment responses, and adverse events were recorded. The immune-related adverse events (AEs), objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) were compared between ESRD and non-ESRD groups.

RESULTS

In total, 129 patients with mUC were enrolled, with 11 patients categorized as the ESRD group. Among these patients with ESRD receiving ICIs, 7 of 11 (63.6%) had high-grade (grade ≥3) AEs, chiefly hematologic toxicity. Some rarely encountered AEs were noted, including toxic epidermal necrolysis, tuberculosis reactivation, ascites, and cytokine release syndrome. Patients in the ESRD group had numerically higher ORR (54.5% vs. 28.8%, p = 0.09), PFS (7.1 vs. 3.5 months, p = 0.42), and OS (not reached vs. 15.4 months) than the non-ESRD group. A multivariate Cox regression model demonstrated that leukocytosis (hazard ratio [HR]: 2.63; 95% confidence interval [CI]: 1.23-5.63; p = 0.01) and neutrophil-to-lymphocyte ratio (HR 2.91; 95% CI: 1.30-6.53; p = 0.01) were independent prognostic factors.

CONCLUSION

Administration of ICIs in patients with mUC and ESRD demonstrated a modest antitumor activity, and should be used with caution for increasing risk of hematologic toxicity.

Melanoma in Solid Organ Transplant Recipients

In this review, we analyze the 3 clinical scenarios related to the development of melanoma in solid organ transplant recipients: melanoma in patients with a history of the tumor prior to a transplant, de novo melanoma following a transplant, and melanoma of donor origin. The main factors to consider in organ-transplant candidates with a history of melanoma are tumor stage, presence or absence of residual disease, and time from diagnosis to transplantation. Solid organ transplant recipients have a greater risk of melanoma than immunocompetent individuals. Mortality is also higher in this population, especially in patients with advanced melanoma, as treatment is especially challenging. Clinical history and physical examination provide the most useful information for preventing donor-to-recipient transmission of melanoma. Donor-derived melanoma has a very poor prognosis.

Molecular Insights in Transmission of Cancer From an Organ Donor to Four Transplant Recipients

Organ donors are systematically screened for infection, whereas screening for malignancy is less rigorous. The true incidence of donor-transmitted malignancies is unknown due to a lack of universal tumor testing in the posttransplant setting. Donor-transmitted malignancy may occur even when not suspected based on donor or recipient factors, including age and time to cancer diagnosis. We describe the detection of a gastrointestinal adenocarcinoma transmitted from a young donor to 4 transplant recipients. Multidimensional histopathologic and genomic profiling showed a CDH1 mutation and MET amplification, consistent with gastric origin. At the time of writing, one patient in this series remains alive and without evidence of cancer after prompt organ explant after cancer was reported in other recipients. Because identification of a donor-derived malignancy changes management, our recommendation is to routinely perform short tandem repeat testing (or a comparable assay) immediately upon diagnosis of cancer in any organ transplant recipient. Routine testing for a donor-origin cancer and centralized reporting of outcomes are necessary to establish a robust evidence base for the future development of clinical practice guidelines.

Evaluation of Checkpoint Inhibitors in Cancer Patients With End-stage Renal Disease on Hemodialysis: Case Series and Review of the Literature

Checkpoint inhibitors (CPIs) have become standard of care for multiple types of malignancies and while end-stage renal disease is not a contraindication, these patients are frequently excluded from clinical trials. As a result, there is limited data regarding the safety and efficacy of CPI use in this patient population. In this case series, we report outcomes and adverse events in 8 patients on hemodialysis treated with CPIs. Treatment was overall well-tolerated with adverse events in 3 of 8 (37.5%) patients, with 1 (12.5%) having a grade 4 adverse event, which is comparable to the rate reported in literature for the overall population receiving CPI. No treatment related deaths were seen. Because of small sample size, efficacy data is limited. Further studies are needed in this patient population to elucidate the true incidence of adverse events and antitumor activity.

How to make the best use of immunotherapy as first-line treatment of advanced/metastatic non-small-cell lung cancer

Antibodies that target programmed death 1 (PD-1) or its ligand [programmed death ligand 1 (PD-L1)] have become a mainstay of first-line treatment of advanced/metastatic non-small-cell lung cancer (NSCLC) without targetable genetic alterations. In this review, we summarize results from recent clinical trials that have evaluated the anti-PD-1 antibodies pembrolizumab and nivolumab and the anti-PD-L1 antibodies atezolizumab and durvalumab as first-line treatment as monotherapy and in combination with chemotherapy, other immunotherapies, and antiangiogenesis agents. We discuss factors that may influence treatment selection, including patient baseline clinical and demographic characteristics, tumor histology, and biomarkers such as PD-L1 expression and tumor mutation burden. While immunotherapy has become a central component of first-line treatment of most patients with advanced NSCLC, important questions remain about how treatment should be managed for individual patients.

Kidney retransplantation after anti-programmed cell death-1 (PD-1)-related allograft rejection

In this report, we describe the first kidney retransplantation performed after anti-programmed cell death-1 (PD-1)-related allograft rejection. In 2014, we administered pembrolizumab (anti-PD-1) for ~9 months to a 57-year-old kidney transplant recipient with metastatic cutaneous squamous cell carcinoma (CSCC). The patient experienced both a complete antitumor response and T cell-mediated allograft rejection requiring reinitiation of hemodialysis. Four-and-a-half years after initiating pembrolizumab, the patient remained without evidence of CSCC relapse and received a kidney transplant from a living-unrelated donor. Ten-and-a-half months after kidney retransplantation, the allograft is functioning well and the patient's CSCC remains in remission. This case illustrates the potential for PD-1 blockade to bring about durable immune-mediated tumor control in chronically immunosuppressed patients, and begins to address the feasibility of kidney retransplantation in patients who have previously received immune checkpoint inhibitor therapy for cancer. Results from this and future cases may help elucidate mechanisms of antitumor immunity and allograft tolerance, and inform updates to transplant decision models. Our report also underscores the need for clinical trials testing novel immunotherapy combinations in solid organ transplant recipients designed to uncouple antitumor and anti-allograft immunity.

Duodenal eosinophils as predictors of symptoms in coeliac disease: a comparison of coeliac disease and non-coeliac dyspeptic patients with controls

Introduction: Duodenal eosinophilia is a key feature of functional dyspepsia, particularly in those with early satiety. Duodenal eosinophilia is also recognised in coeliac disease, although its relevance to symptoms is not understood. We aimed to determine if duodenal eosinophilia is present in patients with coeliac disease presenting with dyspepsia, and whether other histological characteristics were associated with clinical features on presentation.Methods: The coeliac study population comprised 61 patients with a new presentation of coeliac disease to a single centre from 2003 to 2013. A standard symptom assessment was documented for all patients. The control population (55 adults) presenting for endoscopy without coeliac disease was drawn from the same centre with similar demographics for age and gender. Duodenal biopsies from both groups were assessed for eosinophil counts and histological features.Results: Dyspepsia was present in 18.0% of coeliac patients and early satiety in 24.6%. The eosinophil counts were significantly higher in the stomach (12.1/mm² vs. 4.0/mm², p < .001) and duodenum (60.4/mm² vs. 18.0/mm², p < .001) of coeliac patients compared with controls. There was no significant difference in the mean duodenal eosinophil count in coeliac disease with and without early satiety (55.4/mm² vs. 66.9/mm², p = .51). Duodenal eosinophilia was not associated with the severity of coeliac enteropathy. The degree of villous atrophy was associated with iron deficiency at presentation (p = .01), but not symptoms.Conclusions: Although duodenal eosinophil counts are higher in coeliac disease than controls, we were not able to demonstrate an association with presenting symptoms or markers of disease severity.

Pembrolizumab-induced severe rejection and graft intolerance syndrome resulting in renal allograft nephrectomy

INTRODUCTION

Pembrolizumab is a selective anti-programmed cell death protein-1 (PD-1) humanized monoclonal antibody that inhibits PD-1 activity by binding to the PD-1 receptor that is found on activated T-cells. The goal of the treatment is to allow the immune system to target and destroy cancer cells by preventing cancer cells from binding to PD-1 receptors, leading to decreased tumor growth. The activation of T-cells by pembrolizumab not only leads to the destruction of malignant cells but also attacks the donor alloantigens that are present in a renal transplant, resulting in graft rejection.

CASE REPORT

We present a case of a 46-year-old African American female with history of renal transplant who was treated with pembrolizumab for stage IV B endometrial adenocarcinoma and experienced renal transplant rejection and severe graft intolerance syndrome.Management and outcome: Due to ongoing graft intolerance, a transplant nephrectomy was performed. Allograft pathology was consistent with non-viable kidney with tubulitis, interstitial fibrosis and necrosis consistent with transplant rejection without any evidence of malignancy.

DISCUSSION

As emphasized in our case, there is a very high risk of graft rejection in patients who need to be placed on immunomodulators such as pembrolizumab, so the risk versus benefit needs to be assessed and discussed. Our case is unique because pembrolizumab not only caused graft rejection but also severe graft intolerance syndrome which led to transplant nephrectomy. Further guidelines are needed in renal transplant patients requiring PD-1 inhibitors to establish the ideal treatment plan of immunosuppression management and anti-cancer treatments.

Treatment approaches in immunosuppressed patients with advanced cutaneous squamous cell carcinoma

Immunosuppression, both iatrogenic and disease-related, is associated with a greatly increased incidence of cutaneous SCC (cSCC) and with aggressive cSCC and worse disease outcomes. Consequently, rapid access to skin cancer services and prudent surgical choices, such as circumferential margin assessment, is essential when treating advanced cSCC in an immunosuppressed patient. For high-risk cancers and control of cSCC multiplicity, additional strategies should be actively considered within the multidisciplinary clinical care team. These include minimization or revision of immunosuppressive medications, systemic chemoprevention (including retinoids, nicotinamide, capecitabine) and adjuvant therapies such as radiotherapy. Unfortunately, there is a relative paucity of good evidence for many of these treatments in the immunosuppressed. Systemic treatments for metastatic cSCC are often contraindicated in organ transplant recipients, notably checkpoint inhibitor immunotherapy. There are also toxicity concerns with some conventional chemotherapies and EGFR inhibitors. Until recently, clinical trials have largely excluded immunosuppressed individuals. Development of more effective treatment for advanced cSCC in this high-risk group and prospective clinical trials are now research priorities.

Side effect management during immune checkpoint blockade using CTLA-4 and PD-1 antibodies for metastatic melanoma - an update

CTLA-4 and PD-1 play a key role in tumor-induced downregulation of lymphocytic immune responses. Immune checkpoint inhibitors have been shown to alter the immune response to various cancer types. Anti-CTLA-4 and anti-PD-1 antibodies affect the interaction between tumor, antigen-presenting cells and T lymphocytes. Clinical studies of the anti-CTLA-4 antibody ipilimumab and the anti-PD-1 antibodies nivolumab and pembrolizumab have provided evidence of their positive effects on overall survival in melanoma patients. Combined treatment using ipilimumab and nivolumab has been shown to achieve five-year survival rates of 52 %. Such enhancement of the immune response is inevitably associated with adverse events. Knowledge of the spectrum of side effects is essential, both in terms of prevention and management. Adverse events include colitis, dermatitis, hypophysitis, thyroiditis, hepatitis and other, less common autoimmune phenomena. In recent years, considerable progress has been made in the detection and treatment of the aforementioned immune-related adverse events. However, early diagnosis of rare neurological or cardiac side effects, which may be associated with increased mortality, frequently pose a challenge. The present update highlights our current understanding as well as new insights into the spectrum of side effects associated with checkpoint inhibitors and their management.

The successful use of pembrolizumab in a renal transplant recipient with metastatic melanoma

We report a case in which a renal transplant recipient with metastatic melanoma had an excellent response to treatment with second line programmed cell death protein 1 (PD-1) inhibitor therapy, pembrolizumab. Acute cellular allograft rejection on initiation of PD-1 inhibitor was successfully reversed with methylprednisolone. By converting the patient to sirolimus and giving predose prednisolone, pembrolizumab was continued with stable renal function and an excellent oncological response. This case supports the efficacy of PD-1 inhibitors in patients who are chronically immunosuppressed, and suggests an approach to maintain transplant function.

Immune checkpoint inhibitors to treat cutaneous malignancies

As the incidence of cutaneous malignancies continues to rise and their treatment with immunotherapy expands, dermatologists and their patients are more likely to encounter immune checkpoint inhibitors. While the blockade of immune checkpoint target proteins (cytotoxic T-lymphocyte-associated protein-4, programmed cell death-1, and programmed cell death ligand-1) generates an antitumor response in a substantial fraction of patients, there is a critical need for reliable predictive biomarkers and approaches to address refractory disease. The first article of this Continuing Medical Education series reviews the indications, efficacy, safety profile, and evidence supporting checkpoint inhibition as therapeutics for metastatic melanoma, cutaneous squamous cell carcinoma, and Merkel cell carcinoma. Pivotal studies resulting in the approval of ipilimumab, pembrolizumab, nivolumab, cemiplimab, and avelumab by regulatory agencies for various cutaneous malignancies, as well as ongoing clinical research trials, are discussed.

Immune Checkpoint Inhibitors in Patients with Recurrent Hepatocellular Carcinoma after Liver Transplantation: A Case Report and Literature Review

BACKGROUND

Immune checkpoint modulators, such as the programmed death protein-1 (PD-1)/programmed death ligand-1 (PD-L1) inhibitor, cytotoxic T-Lymphocyte-associated antigen 4 (CTLA-4) inhibitor have been investigated with encouraging results for hepatocellular carcinoma (HCC). However, the safety of this strategy in patients with previous liver transplantation (LT) is not well studied.

OBJECTIVE

To explore the safety and feasibility of immune checkpoints inhibitors in recurrent and metastatic HCC patients on a background of LT.

METHODS

A case of recurrent, refractory, metastatic HCC after LT, where PD-1 inhibitor was initiated, was described and related literature was reviewed.

RESULTS

There was complete remission in lung metastases and the partial radiological response of metastatic retroperitoneal lymph node to the drug with no liver graft rejection after 13 cycles of PD- 1 inhibitor injection. PD-1inhibitor, at least in this patient, was verified to play an important role in controlling tumor progression and prolonging patient survival.

CONCLUSION

This novel drug might be a useful method to allow doctors to guarantee a better chance for long-term survival in recurrent, metastatic HCC patients with the previous LT. However, it should be used with caution in allograft recipients due to the risk of acute graft rejection, further larger, prospective studies are needed to determine optimal immunomodulatory therapy to achieve optimal anti-tumor efficacy with transplant liver preservation.

Recent and Emerging Therapies for Cutaneous Squamous Cell Carcinomas of the Head and Neck

OPINION STATEMENT

Cutaneous squamous cell carcinoma (cSCC) of the head and neck is typically managed with Mohs Micrographic Surgery (MMS) for cosmetic reasons. MMS also improves oncologic outcomes for high-risk tumors. Patients with certain high-risk subsets of the disease also benefit from adjuvant radiation therapy. The PD-1 inhibitor, cemiplimab, was recently approved for treatment of locally advanced and metastatic cSCC unamenable to curative surgery or radiation therapy after the drug demonstrated encouraging, durable response rates. Cemiplimab and other systemic immunotherapies are now being evaluated in clinical trials in the neoadjuvant and adjuvant settings as well. Localized immunotherapies are also being studied, including oncolytic viruses such as talimogene laherparepvec, a modified herpes simplex virus previously approved for the treatment of advanced cutaneous melanoma. Most importantly, multidisciplinary care is crucial in optimizing outcomes for patients with high-risk cSCC of the head and neck.

Cutaneous Squamous Cell Carcinoma: From Biology to Therapy

Cutaneous squamous cell carcinoma (CSCC) is the second most frequent cancer in humans and its incidence continues to rise. Although CSCC usually display a benign clinical behavior, it can be both locally invasive and metastatic. The signaling pathways involved in CSCC development have given rise to targetable molecules in recent decades. In addition, the high mutational burden and increased risk of CSCC in patients under immunosuppression were part of the rationale for developing the immunotherapy for CSCC that has changed the therapeutic landscape. This review focuses on the molecular basis of CSCC and the current biology-based approaches of targeted therapies and immune checkpoint inhibitors. Another purpose of this review is to explore the landscape of drugs that may induce or contribute to the development of CSCC. Beginning with the pathogenetic basis of these drug-induced CSCCs, we move on to consider potential therapeutic opportunities for overcoming this adverse effect.

Cutaneous squamous cell carcinoma in the organ transplant recipient

One in twenty solid organ transplant recipients (SOTRs) will develop a highly morbid or fatal cutaneous carcinoma after transplantation. The majority of these cases develop on the head and neck and may require intervention on the part of dermatology, dermatologic surgery, otolaryngology, transplant medicine, radiation oncology, and medical oncology. In this review, we discuss the problem of cutaneous squamous cell carcinoma (cSCC) in SOTRs as well as the prognostic factors and management strategies to care for this population.

In Situ Immune Profiling of Heart Transplant Biopsies Improves Diagnostic Accuracy and Rejection Risk Stratification

Recognizing that guideline-directed histologic grading of endomyocardial biopsy tissue samples for rejection surveillance has limited diagnostic accuracy, quantitative, in situ characterization was performed of several important immune cell types in a retrospective cohort of clinical endomyocardial tissue samples. Differences between cases were identified and were grouped by histologic grade versus clinical rejection trajectory, with significantly increased programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cells suppressed in clinically evident rejections, especially cases with marked clinical-histologic discordance. Programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cell proportions are also significantly higher in "never-rejection" when compared with "future-rejection." These findings suggest that in situ immune modulators regulate the severity of cardiac allograft rejection.

Programmed T cell differentiation: Implications for transplantation

While T cells play a critical role in protective immunity against infection, they are also responsible for graft rejection in the setting of transplantation. T cell differentiation is regulated by both intrinsic transcriptional pathways as well as extrinsic factors such as antigen encounter and the cytokine milieu. Herein, we review recent discoveries in the transcriptional regulation of T cell differentiation and their impact on the field of transplantation. Recent studies uncovering context-dependent differentiation programs that differ in the setting of infection or transplantation will also be discussed. Understanding the key transcriptional pathways that underlie T cell responses in transplantation has important clinical implications, including development of novel therapeutic agents to mitigate graft rejection.

Autoimmune diseases and immune-checkpoint inhibitors for cancer therapy: review of the literature and personalized risk-based prevention strategy

Patients with cancer and with preexisting active autoimmune diseases (ADs) have been excluded from immunotherapy clinical trials because of concerns for high susceptibility to the development of severe adverse events resulting from exacerbation of their preexisting ADs. However, a growing body of evidence indicates that immune-checkpoint inhibitors (ICIs) may be safe and effective in this patient population. However, baseline corticosteroids and other nonselective immunosuppressants appear to negatively impact drug efficacy, whereas retrospective and case report data suggest that use of specific immunosuppressants may not have the same consequences. Therefore, we propose here a two-step strategy. First, to lower the risk of compromising ICI efficacy before their initiation, nonselective immunosuppressants could be replaced by specific selective immunosuppressant drugs following a short rotation phase. Subsequently, combining ICI with the selective immunosuppressant could prevent exacerbation of the AD. For the most common active ADs encountered in the context of cancer, we propose specific algorithms to optimize ICI therapy. These preventive strategies go beyond current practices and recommendations, and should be practiced in ICI-specialized clinics, as these require multidisciplinary teams with extensive knowledge in the field of clinical immunology and oncology. In addition, we challenge the exclusion from ICI therapy for patients with cancer and active ADs and propose the implementation of an international registry to study such novel strategies in a prospective fashion.

Use of Ipilimumab and Pembrolizumab in Metastatic Melanoma in a Combined Heart and Kidney Transplant Recipient: A Case Report

New therapeutic agents such as checkpoint inhibitors are promising strategies in the treatment of metastatic melanoma. Transplant recipients are generally at higher risk of malign diseases. Limited data are available for the use and safety of these agents in this population. We describe a patient who had a stable transplant function over years after a combined heart and kidney transplantation. Immunosuppressive medications included tacrolimus and azathioprine and were later switched to sirolimus and azathioprine. Metastatic melanoma was diagnosed; after detailed explanation of the potential risk, the patient was initially treated with the anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4) antibody ipilimumab but experienced an acute kidney graft rejection and rapid progression. Rejection therapy with high-dose corticosteroids was successful, and kidney function was stabilized. Because of the urgent request of the patient for additional therapy, he received a PD-1 inhibitor. Acute kidney graft rejection resulted, with indication for acute dialysis. He developed severe candida pneumonia and died despite extensive antimicrobial therapy. Checkpoint inhibitors have become the standard in a broad entity of tumors. Organ transplant patients are at higher risk of developing malignant diseases. Limited data are available for the use of checkpoint inhibitors in this subgroup, and the use of checkpoint inhibitors is associated with a high risk of graft rejection.

Immune Checkpoint Inhibitor Nephrotoxicity: Update 2020

Immune checkpoint inhibitors (ICPIs) have transformed the landscape of oncology, but are associated with a variety of autoimmune adverse events, including AKI. ICPI-associated AKI (ICPI-AKI) is emerging as an increasingly frequent cause of AKI in patients with cancer, and poses unique diagnostic and management challenges to clinicians who care for these patients. In this review, we describe the incidence and risk factors for ICPI-AKI, including proton pump inhibitor use, CKD, and combination immunotherapy. We discuss the limitations of the various definitions used for ICPI-AKI in prior studies, and propose a novel classification system (definite, probable, and possible ICPI-AKI) that recognizes the diagnostic uncertainty inherent in many cases. We discuss the key clinicopathologic features and treatment strategies for ICPI-AKI, including the role of kidney biopsy versus empirical treatment with steroids. We also explore the under-studied area of ICPI use in the setting of solid organ transplantation, where nephrologists and oncologists must balance the risk of rejection versus treating the underlying malignancy. Finally, we summarize existing data on the role of ICPI rechallenge after an episode of ICPI-AKI.

The Safety and Efficacy of Checkpoint Inhibitors in Transplant Recipients: A Case Series and Systematic Review of Literature

Limited data exist on safety and efficacy of immune checkpoint inhibitors (ICIs) among organ transplant recipients. The objective of this study was to report a case series of two patients with renal transplant who received treatment with an ICI and to conduct a pooled analysis of published cases to describe the safety and efficacy of ICIs in organ transplant patients. A systematic search in the Google Scholar and PubMed databases was carried out to include all the published cases of organ transplant patients who received treatment with ICIs including programmed cell death protein 1 (PD-1), programmed death-ligand 1, or cytotoxic lymphocyte antigen-4 inhibitors since their inscription to January 31, 2019. In the present series of two cases with renal allografts who received pembrolizumab, one patient with squamous cell carcinoma of the skin experienced complete response (CR), whereas another patient with melanoma had a mixed response. Both patients experienced allograft rejection, but graft was salvaged. The pooled analysis of 64 patients published in literature showed that overall allograft rejection rate is 41% in organ transplant recipients following ICI therapy. The graft rejection rate was 44% (17/39) for renal, 39% (7/19) for liver, and 20% (1/5) for cardiac allografts. The highest risk was seen among patients who were treated with PD-1 inhibitors, 20/42 (48%)-13/24 (54%) on nivolumab and 7/18 (39%) on pembrolizumab. The risk was lowest with ipilimumab, 23% (3/13). The overall response rate (CR + partial response [PR]) was 20% with ipilimumab, 26% with nivolumab, and 53% with pembrolizumab, whereas disease control rate (CR + PR + stable disease) was 35% with ipilimumab, 37% with nivolumab, and 53% with pembrolizumab. None of the variables including age, gender, type of cancer, type of allograft, type of immunosuppression, time since transplantation to initiation of ICI, and prior history of rejection were significantly associated with the transplant rejection on univariate analysis. The efficacy of ICI among patients with organ transplant appears promising, warranting testing in prospective clinical trials. The risk of rejection and allograft loss is considerable; therefore, the risk and alternative form of therapies should be thoroughly discussed with the transplant patients prior to initiating ICI therapy. IMPLICATIONS FOR PRACTICE: Transplant recipients are at higher risk of developing cancers. Although immune checkpoint inhibitors have been shown to improve the outcome in more than one cancer type, transplant recipients were excluded from these trials. Most of the data on the safety and efficacy of immune checkpoint inhibitors in transplant patients are based upon case series and case reports. The pooled data from these reports suggest that anti-programmed death-ligand 1 inhibitors have reasonable safety and efficacy among organ transplant patients, which warrants testing in clinical trials.

Liver transplantation for hepatocellular carcinoma: Management after the transplant

Hepatocellular carcinoma (HCC) is an increasingly common indication for liver transplantation (LT) in the United States and in many parts of the world. In the last decade, significant work has been done to better understand how to risk stratify LT candidates for recurrence of HCC following transplant using a combination of biomarker and imaging findings. However, despite the high frequency of HCC in the LT population, guidance regarding posttransplant management is lacking. In particular, there is no current evidence to support specific post-LT surveillance strategies, leading to significant heterogeneity in practices. In addition, there are no current recommendations regarding recurrence prevention, including immunosuppression regimen or secondary prevention with adjuvant chemotherapy. Finally, guidance on treatment of disease recurrence is also lacking and there is significant controversy about the use of immunotherapy in transplant recipients due to the risk of rejection. Thus, outcomes for patients with recurrence are poor. This paper therefore provides a comprehensive review of the current literature on post-LT management of patients with HCC and identifies gaps in our current knowledge that are in urgent need of further investigation.