Are heart transplant recipients more likely to develop skin cancer than kidney transplant recipients?

Risk of skin cancer in patients with HIV: A Danish nationwide cohort study

BACKGROUND

The risk of skin cancer in patients with HIV has not been extensively studied.

OBJECTIVE

We sought to determine the risk of skin cancer in patients with HIV and compare it with the risk in the background population.

METHODS

In a matched, nationwide, population-based cohort study, we compared the risk of skin cancer in 4280 patients with HIV from the Danish HIV cohort study with a background population cohort, according to the level of immunosuppression and route of transmission. Primary outcomes were time to first basal cell carcinoma (BCC), squamous cell carcinoma (SCC), or malignant melanoma.

RESULTS

Patients with HIV had an increased risk of BCC and SCC with incident rate ratios of 1.79 (95% confidence interval 1.43-2.22) and 5.40 (95% confidence interval 3.07-9.52), respectively, compared with the background population. We observed no increased risk of malignant melanoma. Low nadir CD4 cell count was associated with an increased risk of SCC. The increased risk of BCC among patients with HIV was restricted to men who had sex with men.

LIMITATIONS

This study was observational and included a small number of patients with melanoma.

CONCLUSION

Patients with HIV have an increased risk of BCC and SCC. Low nadir, but not current, CD4 cell count as a marker of immunosuppression was associated with an increased risk of SCC.

Cancer After Heart Transplantation: A 25-year Single-center Perspective

BACKGROUND

Cancer is a major cause of morbidity and mortality after heart transplantation.

METHODS

We studied 541 heart transplant patients from a single center over a period of 25 years, with a mean follow-up of 10.7 years. We determined incidence, type, risk factors, and prognosis for cancer after heart transplantation.

RESULTS

Cancer was diagnosed in 181 patients, at a mean of 7.7 years after transplantation. Cumulative incidence of cancer at 5, 10, and 20 years was 14%, 29%, and 60%, respectively. The most frequent cancers were spinocellular skin cancer (22%), basocellular skin cancer (19%), lung cancer (16%), lymphoma (11%) and prostate cancer (10%). Age at transplantation > 50 years (hazard ratio, 2.9; P < .001) and male recipient gender (hazard ratio, 1.7; P = .038) were significant risk factors for posttransplant malignancy on multivariate Cox proportional hazards analysis. Median patient survival after diagnosis of cancer was 2.9 years for patients with noncutaneous cancer, versus 13.1 years for patients with only skin cancer (P < .001).

Risk of skin cancer and other malignancies in kidney, liver, heart and lung transplant recipients 1970 to 2008--a Swedish population-based study

Organ transplant recipients are at increased risk of a wide range of malignancies, especially cutaneous squamous cell carcinomas (SCC). Few previous population-based studies have quantified and compared cancer risks according to graft type and with long-term follow-up. Using nationwide Swedish registers, we identified 10,476 recipients transplanted from 1970 to 2008 and followed them for cancer occurrence. Relative risks of cancer in comparison with the general population were expressed as standardized incidence ratios (SIR) and within the transplanted cohort as incidence rate ratios (IRR). During a total follow-up of 93,432 person-years, patients were diagnosed with 1,175 cancers excluding SCC, and with 2,231 SCC, SIR(cancer excl SCC) 2.4 (95% CI, 2.2-2.5); SIR(SCC) 121 (95% CI, 116-127). Cancer risks were most increased among heart and/or lung recipients SIR(cancer excl SCC) 3.3 (95% CI, 2.8-4.0); SIR(SCC) 198 (95% CI, 174-224), followed by kidney SIR(cancer excl SCC) 2.3 (95% CI, 2.1-2.4); SIR(SCC) 121 (95% CI, 116-127) and liver recipients SIR(cancer excl SCC) 2.3 (95% CI, 1.9-2.8); SIR(SCC) 32 (95% CI, 24-42). During follow-up, risk of cancer excluding SCC remained stable while risk of SCC tripled over 20 years irrespective of graft type, partly due to a subgroup of patients developing new SCCs at a rapidly increasing rate. In summary, post-transplant cancer risk varied by transplanted organ and by cancer site, with the bulk of the excess risk driven by an exceptionally high and accelerating risk of SCC. These findings underscore the importance of regular skin screening in organ transplant recipients.

Is there a role for proliferation signal/mTOR inhibitors in the prevention and treatment of de novo malignancies after heart transplantation? Lessons learned from renal transplantation and oncology

With the development of new immunosuppressive agents, the majority of transplant recipients are surviving for over a decade, and malignancy has become a major burden on long-term survival. Reducing the incidence of post-transplant malignancies is especially important in heart transplantation where the risk of malignancies is higher than in other organ transplants. Everolimus and sirolimus, the proliferation signal inhibitors (PSIs) or mammalian target-of-rapamycin (mTOR) inhibitors, now provide new strategies for immunosuppression because of their proven efficacy that translates to a reduction in doses of calcineurin inhibitors needed to prevent acute rejection. In addition, the anti-proliferative effects of this class of drugs raise the possibility that they may be effective for reducing the risk of malignancies after solid-organ transplantation. Despite the paucity of direct clinical evidence for this effect in heart transplant patients, observations from renal transplant recipients suggest that the anti-proliferative actions of PSIs/mTOR inhibitors may also protect against malignancies in heart transplant recipients. This potential for an anti-cancer effect is further supported by the emerging data on the use of PSIs/mTOR inhibitors in non-transplant oncology patients. Reviewed in this article are the incidence rates of malignancies after solid-organ transplantation, and the evidence for anti-cancer effects of PSIs/mTOR inhibitors in renal transplant recipients and in non-transplant patients. Also discussed are the implications of these observational data for future studies on the reduction of malignancies after heart transplantation.

Evaluation of Posttransplantation Malignancies Compared With De Novo Tumors

It is uncertain whether tumors arising in transplant patients resemble ones that develop de novo in pathogenesis, morphology, and behavior. This study sought to investigate some clinical, morphological, and immunohistochemical features of several posttransplantation malignancies compared with similar de novo tumors. The study group consisted of 40 malignant tumors encountered in 1350 transplant patients (1229 kidneys, 113 livers, 8 hearts) between 1986 and 2006. Tumors with 3 or more examples were compared with randomly selected controls. These included Kaposi's sarcoma (n=14); extranodal lymphoma (n=9); squamous cell carcinoma (n=6); and nodal lymphoma (n=3). The variables that were analyzed were the localization, predisposing lesions, degree of differentiation, and host response. For lymphomas, we also determined histological subtype, origin, and Ki-67 proliferation index. Most tumors (36/40, 90%) occurred in patients with renal transplants. However, the relative frequency was higher among liver transplant cases (3.53% vs 2.92% for kidney transplants). No malignancy was seen in heart transplant cases. Squamous cell carcinomas were better differentiated (P<.05) compared with controls and they were more frequently associated with precursor lesions (P<.05). Kaposi's sarcomas involved internal organs more frequently in posttransplant patients, and the Ki-67 proliferation index was higher in posttransplantation nodal lymphomas. However, these factors were not significantly different (P>.05). Our findings suggested that certain posttransplantation malignancies display unique characteristics compared with their de novo counterparts.

Azathioprine in dermatology: The past, the present, and the future

For several decades, dermatologists have utilized azathioprine to treat numerous debilitating skin diseases. This synthetic purine analog is derived from 6-mercaptopurine. It is thought to act by disrupting nucleic acid synthesis and has recently been found to interfere with T-cell activation. The most recognized uses of azathioprine in dermatology are for immunobullous diseases, generalized eczematous disorders, and photodermatoses. In this comprehensive review, the authors present recent advancements in the understanding of azathioprine and address aspects not covered in prior reviews. They (1) summarize the history of azathioprine; (2) discuss metabolism, integrating information from recent publications; (3) review the mechanism of action with attention paid to the activities of azathioprine not mediated by its 6-mercaptopurine metabolites and review new data about inhibition by azathioprine of the CD28 signal transduction pathway; (4) thoroughly examine thiopurine s-methyltransferase genetics, its clinical relevance, and interethnic variations; (5) review prior uses of azathioprine in the field of dermatology and grade the level of evidence; (6) discuss the use of azathioprine in pregnancy and pediatrics; review (7) key drug interactions and (8) adverse effects; (9) suggest a dosing and monitoring approach different from prior recommendations; and (10) explore the future of azathioprine, focusing on laboratory considerations and therapeutic application.

Reduction of immunosuppression for transplant-associated skin cancer: expert consensus survey

BACKGROUND

Reduction of immunosuppression is considered a reasonable adjuvant therapeutic strategy in solid-organ transplant recipients experiencing multiple or high-risk skin cancers. However, the literature provides no guidance about what threshold of cancer development would warrant initiation of reduction of immunosuppression.

OBJECTIVES

To develop expert consensus guidelines for initiation of reduction of transplant-associated immunosuppression for solid-organ transplant recipients with severe skin cancer.

METHODS

An expert consensus panel was convened by the International Transplant Skin Cancer Collaborative and Skin Care for Organ Transplant Patients Europe Reduction of Immunosuppression Task Force. Thirteen hypothetical patient scenarios with graduated morbidity and mortality risks were presented and mean and mode expert opinions about appropriate level of reduction of systemic immunosuppression (mild, moderate, severe) were generated.

RESULTS

Mild reduction of transplant-associated immunosuppression was considered warranted once multiple skin cancers per year developed or with individual high-risk skin cancers. Moderate reduction was considered appropriate when patients experienced > 25 skin cancers per year or for skin cancers with a 10% 3-year risk of mortality. Severe reduction was considered warranted only for life-threatening skin cancers.

CONCLUSIONS

Reduction of immunosuppression is considered a reasonable adjuvant management strategy for transplant recipients with numerous or life-threatening skin cancers. Proposed guidelines are presented for the graduated reduction of immunosuppression coincident with the increasing skin cancer risks.

Development of malignancy following lung transplantation

BACKGROUND

A substantial excess risk of certain malignancies has been demonstrated after organ transplantation. Immunosuppressive treatment to prevent allograft rejection is probably the main cause.

METHODS

We reviewed retrospectively all medical records of the 121 patients that underwent lung and heart-lung transplantation from 1992 until December 2004. We compared our results to the International Society for Heart and Lung Transplantation (ISHLT) registry data and previous reports concerning lung transplantation.

RESULTS

102 of the 121 patients survived for 3 months to 12 years. Malignancies developed in 16 patients, as follows: lymphoproliferative disorder in 3, Kaposi's sarcoma in 3, other nonmelanoma skin cancers in 7, urinary bladder transitional cel carcinoma in 3, and colon cancer in 1. Patients with malignancy were older at transplantation than those without (mean +/- SD, 54.1+/-7.8 vs. 49.5+/-14.2 years; P=0.03). Fourteen had smoked in the past. Four died of bronchiolitis obliterans. In comparison with the ISHLT, we observed more skin cancer and transitional cell carcinoma (12.8% vs. 0.7% and 3.8% vs. 0.03%, respectively) and a similar frequency of posttransplant lymphoproliferative disease.

CONCLUSIONS

We conclude that malignancy is a common complication after lung transplantation. In Israel, which is sunny most of the year, skin cancers and transitional cell carcinoma of bladder are more common. Modification of the immunosuppression late posttransplantation may reduce the risk of cancer. Patients should also be counseled to avoid sun exposure and ensure adequate hydration.

Incidence of cancer after immunosuppressive treatment for heart transplantation

Prolonged or intensive immunosuppressive therapy used after organ transplantation is complicated by an increased incidence of cancer. Striking differences in incidence are observed in heart and heart-lung transplant recipients when compared with renal transplant patients. The most significant increase was in the incidence of lymphomas in cardiac versus renal patients. Moreover, a two-fold greater increase of all neoplasms was found in cardiac recipients, with nearly a six-fold increase in visceral tumors. Several factors may account for these differences. In cardiac allograft recipients, intensive immunosuppression is frequently used to reverse acute rejection and the highest number of cardiac transplants was performed in the era of polypharmacy, usually consisting of triple therapy.

Reduction of immunosuppression for transplant-associated skin cancer: rationale and evidence of efficacy

BACKGROUND

Solid organ transplant recipients may develop numerous or life-threatening skin cancers. In addition to aggressive standard treatment of skin cancer, reduction of immunosuppression has been considered an adjuvant therapeutic strategy, albeit without direct proof of efficacy.

OBJECTIVE

To review the rationale for and evidence supporting the efficacy of reduction of immunosuppression for severe skin cancer in transplant recipients.

METHODS

Review of the literature regarding direct and indirect evidence on reduction of immunosuppression for transplant-associated skin cancer.

RESULTS

Although there are no randomized controlled trials of reduction of immunosuppression as a therapeutic intervention for transplant patients with skin cancer, multiple lines of evidence suggest that this strategy may be an effective adjuvant therapy. A randomized trial has demonstrated a lower incidence of skin cancer in transplant recipients after reduction of immunosuppression, albeit in a cohort not previously affected by skin cancer. Case series of reduction or cessation of immunosuppression demonstrate a lower incidence of skin cancer or improved outcomes of preexisting skin cancer. Lower overall immunosuppression is associated with a lower incidence of skin cancer. Multiple cancers affecting the skin have been shown to regress with reduction of immunosuppression.

CONCLUSIONS

Reduction of immunosuppression may be an effective adjuvant therapeutic strategy when confronting severe transplant-associated skin cancer. The risks of reduction of immunosuppression must be better defined, and randomized trials of this strategy are necessary.

The historical link between solid-organ transplantation, immunosuppression, and skin cancer

BACKGROUND

Skin cancers are more common in organ transplant recipients than in the general population.

OBJECTIVE

The objective of this study was establish the historical link between organ transplantation, immunosuppression, and the development of skin cancer.

METHODS

The pertinent literature in cutaneous oncology and transplantation is reviewed.

RESULTS

There is a historical link between organ transplants, immunosuppression, and the subsequent development of skin cancers.

CONCLUSIONS

Organ transplant recipients have more skin cancer than those in the general population and this is temporally related to their degree of immunosuppression.