High azathioprine dose and lip cancer risk in liver, heart, and lung transplant recipients: A population-based cohort study

Azathioprine for people with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is an immune-mediated, chronic, inflammatory demyelinating disease of the central nervous system, impacting around 2.8 million people worldwide. Characterised by recurrent relapses or progression, or both, it represents a substantial global health burden, affecting people, predominantly women, at a young age (the mean age of diagnosis is 32 years). Azathioprine is used to treat chronic inflammatory and autoimmune diseases, and it is used in clinical practice as an off-label intervention for MS, especially where access to on-label disease-modifying treatments (DMTs) for MS is limited. Given this, a review of azathioprine's benefits and harms would be timely and valuable to inform shared healthcare decisions.

OBJECTIVES

To evaluate the benefits and harms of azathioprine (AZA) for relapsing and progressive multiple sclerosis (MS), compared to other disease-modifying treatments (DMTs), placebo or no treatment. Specifically, we will assess the following comparisons. AZA compared with other DMTs or placebo as first-choice treatment for relapsing forms of multiple sclerosis AZA compared with other DMTs or placebo for relapsing forms of MS when switching from another DMT AZA compared with other DMTs or placebo as first-choice treatment for progressive forms of MS AZA compared with other DMTs or placebo for progressive forms of MS when switching from another DMT SEARCH METHODS: We conducted an extensive search for relevant literature using standard Cochrane search methods. The most recent search date was 9 August 2023.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) lasting 12 months or more that compared azathioprine versus DMTs, placebo or no intervention in adults with MS. We considered evidence from non-randomised studies of interventions (NRSIs) as these studies may provide additional evidence not available from RCTS. We excluded cluster-randomised trials, cross-over trials, interrupted time series, case reports and studies of within-group design with no control group.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. There were three outcomes we considered to be critical: disability, relapse and serious adverse events (SAEs, as defined in the studies). We were also interested in other important outcomes: quality-of-life (QoL) impairment (mental score), short-term adverse events (gastrointestinal disorders), long-term adverse events (neoplasms) and mortality.

MAIN RESULTS

We included 14 studies: eight RCTs (1076 participants included in meta-analyses) and six NRSIs (1029 participants). These studies involved people with relapsing and progressive MS. Most studies included more women (57 to 83%) than men, with participants' average age at the onset of MS being between 29.4 and 33.4 years. Five RCTs and all six NRSIs were conducted in Europe (1793 participants); two RCTs were conducted in the USA (126 participants) and one in Iran (94 participants). The RCTs lasted two to three years, while NRSIs looked back up to 10 years. Four studies received some funding or support from commercial interests and five were funded by government or philanthropy; the other five provided no information about funding. There are three ongoing studies. Comparison groups included other DMTs (interferon beta and cyclosporine A), placebo or no treatment. Below, we report on azathioprine as a 'first choice' treatment compared to interferon beta for people with relapsing MS. None of the studies reported on any critical or important outcome for this comparison for progressive MS. No study was retrieved comparing azathioprine to placebo or other DMTs for either relapsing or progressive MS. Furthermore, the NRSIs did not provide information not already covered in the RCTs. Azathioprine as a first-choice treatment compared to other DMTs (specifically, interferon beta) for relapsing MS - The evidence is very uncertain about the effect of azathioprine on the number of people with disability progression over two years compared to interferon beta (risk ratio (RR) 0.19, 95% confidence interval (CI) 0.02 to 1.58; 1 RCT, 148 participants; very low certainty evidence). - Azathioprine may decrease the number of people with relapses over a one- to two-year follow-up compared to interferon beta (RR 0.61, 95% CI 0.43 to 0.86; 2 RCTs, 242 participants; low-certainty evidence). - Azathioprine may result in a possible increase in the number of people with SAEs over two years in comparison with interferon beta (RR 6.64, 95% CI 0.35 to 126.27; 1 RCT, 148 participants; low-certainty evidence). - The evidence is very uncertain about the effect of azathioprine on the number of people with the short-term adverse event of gastrointestinal disorders over two years compared to interferon beta (RR 5.30, 95% CI 0.15 to 185.57; 2 RCTs, 242 participants; very low certainty evidence). We found no evidence comparing azathioprine to other DMTs for QoL impairment (mental score), long-term adverse events (neoplasms) or mortality.

AUTHORS' CONCLUSIONS

Azathioprine has been proposed as an alternative treatment for MS when access to approved, on-label DMTs is limited, especially in resource-limited settings. The limited evidence available suggests that azathioprine may result in a modest benefit in terms of relapse frequency, with a possible increase in SAEs, when compared to interferon beta-1b, for people with relapsing-remitting multiple sclerosis. The evidence for the effect on disability progression and short-term adverse events is very uncertain. Caution is required in interpreting the conclusions of this review since our certainty in the available evidence on the benefits and harms of azathioprine in multiple sclerosis is low to very low, implying that further evidence is likely to change our conclusions. An important limitation we noted in the available evidence is the lack of long-term comparison with other treatments and the failure of most studies to measure outcomes that are important to people with multiple sclerosis, such as quality of life and cognitive decline. This is especially the case in the evidence relevant to people with progressive forms of multiple sclerosis.

Clinical Characteristics and Outcomes of Generalized Myasthenia Gravis in Malaysia: A Single-Center Experience

BACKGROUND AND PURPOSE

Myasthenia gravis (MG) is clinically heterogeneous and can be classified into subgroups according to the clinical presentation, antibody status, age at onset, and thymic abnormalities. This study aimed to determine the clinical characteristics and outcomes of generalized MG (GMG) patients based on these subgroups.

METHODS

Medical records of MG patients from 1976 to 2023 were reviewed retrospectively. Patients with pure ocular MG were excluded. Data on demographic, clinical characteristics, laboratory features, and outcomes were analyzed.

RESULTS

This study included 120 GMG patients. There was a slight preponderance of female patients over male patients (male:female ratio=1:1.3), with the age at onset exhibiting a bimodal distribution. Female patients peaked at a lower age (21-30 years) whereas male patients peaked at a higher age (61-70 years). Most (92%, 105 of 114) patients had positive anti-acetylcholine receptor antibodies. Five patients were also tested for anti-muscle-specific tyrosine kinase antibodies, with two showing positivity. Thymectomy was performed in 62 (52%) patients, of which 30 had thymoma, 16 had thymic hyperplasia, 7 had an involuted thymus, and 6 had a normal thymus. There were significantly more female patients (68% vs. 45%, p=0.011) with early-onset disease (<50 years old) and thymic hyperplasia (33% vs. 0%, p<0.025). Most (71%) of the patients had a good outcome based on the Myasthenia Gravis Foundation of America postintervention status. GMG patients with early-onset disease had a significantly better outcome than patients with a late onset in univariate (58% vs. 37%, p=0.041) and multivariate (odds ratio=4.68, 95% confidence interval=1.17-18.64, p=0.029) analyses.

CONCLUSIONS

Female patients with early-onset MG and thymic hyperplasia had significantly better outcomes, but only early-onset disease was independently associated with a good outcome. These findings are comparable with those of other studies.

Anti-inflammatory Therapy for Sarcoidosis

Over 50% of patients with sarcoidosis will require anti-inflammatory therapy at some point in their disease course. Indications for therapy are to improve health-related quality of life, prevent or arrest organ dysfunction (or organ failure) or avoid death. Recently published treatment guidelines recommended a stepwise approach to therapy however there are some patients for whom up front combination or more intense therapy maybe reasonable. The last decade has seen an explosion of studies and trials evaluating novel therapeutic agents and treatment strategies. Currently available anti-inflammatory therapies and several novel therapies are discussed here.

A review of heart transplant immunosuppressants and nonmelanoma skin cancer

Heart transplant recipients experience high rates of skin cancer, likely due to greater length or dosage of immunosuppression. We review the impact of immunosuppressive medications on development of nonmelanoma skin cancer (NMSC) in heart transplant recipients. The authors searched keywords "heart transplant" and "nonmelanoma skin cancer" on PubMed in October 2022 for eligible articles available in English. Articles were selected for inclusion based on relevance to heart transplantation and NMSC. If any cited articles within included articles were related to our search they were also included. Of the 29 identified articles, 18 met the inclusion criteria with a total of 11,699 patients. Two studies found that tacrolimus and azathioprine increased the risk of NMSC. Five studies demonstrated that tacrolimus, everolimus, sirolimus, azathioprine and mycophenolate mofetil decreased the risk of NMSC. Three studies described that cyclosporine, tacrolimus, everolimus, sirolimus, azathioprine, mycophenolate mofetil and prednisone had no significant association with the development in NMSC. Two studies did not specify the correlation between immunosuppressant use and NMSC development. Ten studies did not discuss the association of immunosuppressants use with the development of NMSC. Our review highlights the commonly used immunosuppressive drugs that can impact the development of NMSC in heart transplant recipients. A management strategy in immunosuppression-associated skin cancers may ultimately involve adjusting the immunosuppressive regimen. This review serves as a summary of the most commonly used immunosuppressive drugs in heart transplant patients and their tumorigenic mechanisms to guide recommendations for dermatologic follow-up in heart transplant recipients.

HIV-associated photodermatitis in African populations

Photosensitive dermatoses are seen in 5% of HIV-infected persons. These include drug- and chemical-induced photoallergic and phototoxic reactions, chronic actinic dermatitis of HIV, photo lichenoid drug eruptions, and porphyria. Data on photodermatitis in HIV are limited to case reports and series. The pathogenesis is not completely understood and includes a th2 phenotype in HIV which results in impaired barrier function and resultant allergen sensitisation as well as immune dysregulation. The objective of this manuscript is to review the literature on the clinical phenotype, pathogenesis, role of photo and patch testing, outcomes, and treatment of photodermatitis in HIV in an African population.

Gastrointestinal and Pancratohepatobiliary Cancers: A Comprehensive Review on Epidemiology and Risk Factors Worldwide

A significant number of cancer cases are afflicted by gastrointestinal cancers annually. Lifestyle and nutrition have a huge effect on gastrointestinal function, and unhealthy habits have become quite widespread in recent decades, culminating in the rapid growth of gastrointestinal cancers. The most prevalent cancers are lip and mouth cancer, esophageal cancer, gastric cancer, liver and bile duct cancer, pancreatic cancer, and colorectal cancer. Risk factors such as red meat consumption, alcohol consumption, tea, rice, viruses such as Helicobacter pylori and Ebstein Bar Virus (EBV), along with reduced physical activity, predispose the gastrointestinal tract to damage and cause cancer. According to the rapid increase of cancer incidence and late diagnosis of gastrointestinal malignancies, further epidemiological researches remain necessary in order to make appropriate population-based preventive policies. In this study, we reviewed clinical symptoms, risk factors, preventative measures, as well as incidence and mortality rates of gastrointestinal malignancies worldwide with focus on Iranian population.

Malignancy Risk Associated with Mycophenolate Mofetil or Azathioprine in Patients with Fibrotic Interstitial Lung Disease

Some of these results were presented in abstract form at the 2021 American Thoracic Society International Conference, May 2021.

Malignancy among adult heart transplant recipients following patient-tailored dosing of anti-thymocyte globulin: a retrospective, nested case-control study of individualized dosing

Post-transplant malignancy is diagnosed in approximately 18% of heart transplant patients and is a leading cause of death post-transplant. One modifiable risk factor is the type and amount of immunosuppression received. Contemporary rabbit anti-thymocyte globulin (rATG) dosing strategy using T-cell-guided dosing, and its effect on malignancy in heart transplant patients is unclear. This was a single-center, retrospective chart review of heart transplant recipients receiving rATG for induction. Patients diagnosed with malignancy post-transplant were matched 1:2 to controls using a nested case-control design. The primary endpoint was to determine the relative risk of rATG exposure with the actual incidence of malignancy post-transplant. The secondary endpoint was the impact of maintenance immunosuppression on malignancy risk. Of the 126 patients included in the study, 25 developed malignancy and were matched to 50 control patients. The median cumulative rATG dose in milligrams (mg) between groups was 365 mg in malignancy cases and 480 mg in controls (OR 0.90, 95% CI 0.75-1.08, P = 0.28). In both the univariate and multivariable analysis, there was no statistically significant difference in malignancy risk found with any maintenance immunosuppressant. The results of this study showed that patient-tailored rATG dosing strategies may not be associated with malignancy development as previously thought.

The role of drugs and selected dietary factors in cutaneous squamous cell carcinogenesis

Cutaneous squamous cell carcinoma represents the second most common non-melanoma skin cancer and its incidence increases worldwide. This review provides an overview of selected exogenous risk factors for cutaneous squamous cell carcinoma, which include drugs (azathioprine, calcineurin inhibitors, hydrochlorothiazide, angiotensin-converting-enzyme inhibitors) and few dietary factors (fat meet, whole milk products, arsenic) to better understand squamous skin cancer etiopathogenesis. Ingredients such as leafy vegetables, nuts, fish, caffeine, niacin are preventive factors for cutaneous squamous cell cancer. The heart transplant recipients have an increased risk of squamous cell carcinoma development than kidney or liver transplant ones and switching photosensitizing azathioprine to mycophenolate mofetil can reduce the incidence of cutaneous squamous cell carcinoma. The great attention should be paid to early change of cardiac photosensitizing antihypertensive drugs to non-photosensitizing ones among patients with a history of prior skin cancers and among organ transplant recipients. Based on current knowledge that ultra-violet radiation is the main risk factor for squamous cell carcinoma development, promotion of the skin self-examination, photoprotection, tanning bed avoidance and early skin cancer diagnosis is important for this tumour prevention.

Risk of Rare Cancers Among Solid Organ Transplant Recipients

BACKGROUND

Immunosuppressed solid organ transplant recipients (SOTRs) have elevated rates of certain rare cancers caused by viruses. Evaluating risk of rare cancers among SOTRs may provide etiological clues for additional cancers linked to poor immunity and viral infections.

METHODS

We performed a cohort study of 262 455 SOTRs (1987-2014) from the US SOTR registry linked to 17 population-based cancer registries. First cancers in SOTRs were categorized using an established classification scheme based on site and histology. Standardized incidence ratios (SIRs) compared risk in SOTRs with the general population. We used Poisson regression to calculate incidence rate ratios according to immune-related SOTR characteristics, including time since transplant (ie, duration of immunosuppression). All statistical tests were 2-sided.

RESULTS

We examined 694 distinct cancer subtypes, with 33 manifesting statistically significantly elevated SIRs (Bonferroni P < 7.2 × 10-5). All 33 are rare (incidence <6 per 100 000 person-years) and several have known viral etiology (eg, Merkel cell carcinoma: SIR = 24.7, 95% confidence interval [CI] = 20.8 to 29.1). Additional cancers that were increased include squamous cell carcinomas of the lip (SIR range = 18.3-19.8), eye and adnexa (SIR = 13.8, 95% CI = 7.9 to 22.3), salivary gland (SIR = 9.3, 95% CI = 6.1 to 13.5), and nasal cavity and sinuses (SIR = 4.5, 95% CI = 2.8 to 6.8); sebaceous adenocarcinoma (SIR = 34.3, 95% CI = 26.3 to 44.0); malignant fibrous histiocytoma (15.4); and subtypes of bladder, kidney, lung, and colon cancer (SIR range = 3.2-13.3). Incidence of several cancers increased over time since transplant (Ptrend < .05), including squamous cell carcinomas of the lip, salivary gland, and anogenital sites.

CONCLUSIONS

SOTRs experience elevated rates of several rare cancers. Because some of these cancers exhibit aggressive behavior with poor outcomes, it is important to further characterize the role of immunity and the potential involvement of oncogenic viruses to improve prevention and treatment.

Post-transplant malignancy in solid organ transplant recipients in Ireland, The Irish Transplant Cancer Group

OBJECTIVE

Solid organ transplant recipients are at increased risk of cancer compared to the general population. To date, this risk in Ireland has not been investigated. We conducted a national registry study of cancer incidence following solid organ transplantation.

METHODS

National centers for solid organ transplantation supplied their respective registry databases to cross-reference with episodes of malignancy from the National Cancer Registry Ireland (NCRI) between 1994 and 2014. Standardized incidence of cancer post-transplant was compared to the general population by means of standardized incidence ratios (SIRs), and between solid organ transplant types by incidence rate ratios.

RESULTS

A total of 3346 solid organ transplant recipients were included in this study. Kidney transplant recipients constituted the majority of participants (71.2%), followed by liver (16.8%), heart (6.4%), and lung (5.6%) transplants. The most common cancers within the composite of all transplant recipients included the following (SIR [95% CI]): squamous and basal cell carcinoma (20.05 [17.97, 22.31] and 7.16 [6.43, 7.96], respectively), non-Hodgkin lymphoma (6.23 [4.26, 8.59]), and renal cell carcinoma (3.36 [1.96, 5.38]).

CONCLUSIONS

This study reports the incidence of cancer following solid organ transplantation in Ireland. These results have significant national policy implications for surveillance, and early diagnosis in this patient group.

Risk of lip cancer after solid organ transplantation in the United States

Solid organ transplant recipients have an increased risk of lip cancer, but the reasons are uncertain. Using data from the Transplant Cancer Match Study, we describe the epidemiology of lip cancer among 261 500 transplant recipients in the United States. Two hundred thirty-one lip cancers were identified, corresponding to elevated risks for both invasive and in situ lip cancers (standardized incidence ratios of 15.3 and 26.2, respectively). Invasive lip cancer incidence was associated with male sex (adjusted incidence rate ratio [aIRR] 2.01, 95% CI 1.44-2.82), transplanted organ (0.33, 0.20-0.57, for liver transplants and 3.07, 1.96-4.81, for lung transplants, compared with kidney transplants), and racial/ethnic groups other than non-Hispanic whites (0.09, 0.04-0.2). In addition, incidence increased with age and during the first 3 years following transplant, and was higher in recipients prescribed cyclosporine/azathioprine maintenance therapy (aIRR 1.79, 95% CI 1.09-2.93, compared with use of tacrolimus/mycophenolate mofetil) and following a diagnosis of cutaneous squamous cell carcinoma (4.21, 2.69-0.94). The elevation in lip cancer incidence is consistent with an effect of immunosuppression. Notably, the very strong associations with white race and history of prior skin cancer point to an important role for ultraviolet radiation exposure, and cyclosporine and azathioprine may contribute as photosensitizing or DNA damaging agents.

Longitudinal immunosuppression data can minimize misclassification bias in solid organ transplantation cohorts

BACKGROUND

Most cohort studies investigating the effect of immunosuppression on transplant outcomes use drugs at first hospital discharge. We evaluated the extent of drug exposure misclassification and its impact on outcome prediction.

METHODS

We retrospectively collected longitudinal immunosuppression data, at discharge and at 1, 5, 10, and 15 years after transplantation, and outcomes for solid organ transplant recipients 1984-2006 (n = 3133). We compared the risk of death from exposure to individual immunosuppressive drugs (cyclosporine, tacrolimus, azathioprine, and mycophenolate) and dual therapies, as defined by discharge only vs longitudinal immunosuppression data, using adjusted Cox proportional hazards models.

RESULTS

During a median follow-up of 5.2 years, immunosuppressive drugs were altered for 947 (30%) recipients and 955 recipients died. Longitudinal receipt of cyclosporine and azathioprine were associated with an increased risk (HR 1.41, 95% CI 1.07-1.89, and HR 1.34, 95% CI 1.00-1.80), and mycophenolate with a reduced risk (HR 0.35, 0.16-0.78), of death. Recipients on mycophenolate and tacrolimus dual therapy had a lower risk of death compared to those on azathioprine and cyclosporine dual therapy (HR 0.30, 0.10-0.93). The increased risk of death associated with the receipt of cyclosporine or azathioprine was not shown in the analyses based on drugs allocated at discharge, and all of the associations between immunosuppressive regimens and death were strengthened in the analyses based on longitudinal immunosuppression data.

CONCLUSIONS

Cohort findings based on immunosuppressive drugs allocated at discharge should be interpreted with caution due to potential exposure misclassification. The use of granular, longitudinal data on immunosuppressive regimens could improve prediction.

Characteristics of non-melanoma skin cancers of the cutaneous perioral and vermilion lip treated by Mohs micrographic surgery

BACKGROUND

The lip and surrounding perioral region are susceptible to non-melanoma skin cancer, but the distribution of basal cell and squamous cell carcinoma on the cutaneous and vermilion lips has not been fully elucidated.

OBJECTIVE

To investigate the distribution of cutaneous and vermilion lip non-melanoma skin cancer and to better describe risk factors, anatomic location, treatment characteristics and oncologic outcomes.

METHODS

A retrospective comparative case series of patients undergoing Mohs micrographic surgery (MMS) at a single academic centre for lip and perioral basal cell and squamous cell carcinoma was performed over a 5-year period. Demographics, medical comorbidities, surgical characteristics and recurrence status were extracted.

RESULTS

Forty-five vermilion and 116 cutaneous lip cancers were identified. Basal cell carcinoma (BCC) was more common in the cutaneous perioral region, while squamous cell carcinoma (SCC) was more common on the vermilion lip (P < 0.001). BCCs were more common on the upper vermilion lip and SCCs were more common on the lower vermilion lip (P < 0.001). Within the cutaneous perioral region, both BCCs and SCCs were more common on the upper perioral surface (P = 0.002). Male gender was associated with lower lip SCC (P = 0.015). Smoking, immunosuppression, anticoagulant use and hydrochlorothiazide use were not associated with cancer type or location. Recurrences were rare, but more common in vermilion lip cancers (6.6%) compared to perioral cutaneous cancers (0.8%). Outcomes for all groups were similar; BCCs of the vermilion lip had significantly greater mean MMS stages (P < 0.001) as did SCCs (P = 0.05).

CONCLUSION

Basal cell carcinoma is more commonly encountered on the cutaneous lip, whereas SCC is more common on the vermilion lip. Within the vermilion lip, BCC favours the upper lip, while SCC favours the lower lip. Within the cutaneous perioral region, both BCC and SCC favour the upper cutaneous tissue. Early stage lip cancers are curable by Mohs micrographic surgery with rare recurrences.

Etiology of increased cancer incidence after solid organ transplantation

Over the past decades, there has been an encouraging increase in survival after solid organ transplantation. However, with longer life spans, more transplant recipients are at risk of dying with functioning grafts from illnesses such as cancer and cardiovascular conditions. Malignancy has emerged as an important cause of death in transplant recipients and is expected to become the leading cause of death in transplanted patients within the next decade. While it is known that solid organ transplant recipients have a three to five-fold increased risk of developing cancer compared with the general population, the mechanisms that lead to the observed excess risk in transplant recipients are less clear. This review explores the etiology of the increased cancer incidence in solid organ transplant including the effect of immunosuppressants on immunosurveillance and activation of oncogenic viruses, and carcinogenic effects of these medications; the role of chronic stimulation of the immune system on the development of cancer; and the impact of pre-existing cancer risk factors and factors related to end-stage organ disease on the cancer excess incidence in solid organ transplant recipients.

The 2018 ISHLT/APM/AST/ICCAC/STSW recommendations for the psychosocial evaluation of adult cardiothoracic transplant candidates and candidates for long-term mechanical circulatory support

The psychosocial evaluation is well-recognized as an important component of the multifaceted assessment process to determine candidacy for heart transplantation, lung transplantation, and long-term mechanical circulatory support (MCS). However, there is no consensus-based set of recommendations for either the full range of psychosocial domains to be assessed during the evaluation, or the set of processes and procedures to be used to conduct the evaluation, report its findings, and monitor patients' receipt of and response to interventions for any problems identified. This document provides recommendations on both evaluation content and process. It represents a collaborative effort of the International Society for Heart and Lung Transplantation (ISHLT) and the Academy of Psychosomatic Medicine, American Society of Transplantation, International Consortium of Circulatory Assist Clinicians, and Society for Transplant Social Workers. The Nursing, Health Science and Allied Health Council of the ISHLT organized a Writing Committee composed of international experts representing the ISHLT and the collaborating societies. This Committee synthesized expert opinion and conducted a comprehensive literature review to support the psychosocial evaluation content and process recommendations that were developed. The recommendations are intended to dovetail with current ISHLT guidelines and consensus statements for the selection of candidates for cardiothoracic transplantation and MCS implantation. Moreover, the recommendations are designed to promote consistency across programs in the performance of the psychosocial evaluation by proposing a core set of content domains and processes that can be expanded as needed to meet programs' unique needs and goals.

Long-term Change in the Risk of Skin Cancer After Organ Transplantation: A Population-Based Nationwide Cohort Study

Importance

The high risk of skin cancer after organ transplantation is a major clinical challenge and well documented, but reports on temporal trends in the risk of posttransplant cutaneous squamous cell carcinoma (SCC) are few and appear contradictory.

Objective

To study temporal trends for the risk of skin cancer, particularly SCC, after organ transplantation.

Design, Setting, and Participants

Population-based, nationwide, prospective cohort study of 8026 patients receiving a kidney, heart, lung, or liver transplant in Norway from 1968 through 2012 using patient data linked to a national cancer registry. The study was conducted in a large organ transplantation center that serves the entire Norwegian population of approximately 5.2 million.

Exposures

Receiving a solid organ transplant owing to late-stage organ failure, followed by long-term immunosuppressive treatment according to graft-specific treatment protocols.

Main Outcomes and Measures

Occurrence of first posttransplant SCC, melanoma, or Kaposi sarcoma of the skin. Risk of skin cancer was analyzed using standardized incidence ratios (SIRs) and, for SCC, multivariable Poisson regression analysis of SIR ratios, adjusting for 5-year time period of transplantation, different follow-up time, age, sex, and type of organ.

Results

The study cohort included 8026 organ transplant recipients, 5224 men (65.1%), with a mean age at transplantation of 48.5 years. Median follow-up time was 6.7 years per recipient; total follow-up time, 69 590 person-years. The overall SIRs for SCC, melanoma, and Kaposi sarcoma were 51.9 (95% CI, 48.4-55.5), 2.4 (95% CI, 1.9-3.0), and 54.9 (95% CI, 27.4-98.2), respectively. In those who underwent transplantation in the 1983-1987 period, the unadjusted SIR for SCC was 102.7 (95%, 85.8-122.1), declining to 21.6 (95% CI, 16.8-27.0) in those who underwent transplantation in the 2003-2007 period. Adjusting for different follow-up times and background population risks, as well as age, graft organ, and sex, a decline in the SIR for SCC was found, with SIR peaking in patients who underwent transplantation in the 1983-1987 period and later declining to less than half in patients who underwent transplantation in the 1998-2002, 2003-2007, and 2008-2012 periods, with the relative SIRs being 0.42 (95% CI, 0.32-0.55), 0.31 (95% CI, 0.22-0.42), and 0.44 (95% CI, 0.30-0.66), respectively.

Conclusions and Relevance

The risk of SCC after organ transplantation has declined significantly since the mid-1980s in Norway. Less aggressive and more individualized immunosuppressive treatment and close clinical follow-up may explain the decline. Still, the risk of SCC in organ transplant recipients remains much higher than in the general population and should be of continuous concern for dermatologists, transplant physicians, and patients.