Malignancy after renal transplantation: incidence and role of type of immunosuppression

Prevalence of Post-Heart Transplant Malignancies: A Systematic Review and Meta-Analysis

The prevalence of different cancers after heart transplant (HT) is unclear due to small and conflicting prior studies. Herein, we report a systematic review and meta-analysis to highlight the prevalence and pattern of malignancies post-HT. We conducted an extensive literature search on PubMed, Scopus, Cochrane databases for prospective or retrospective studies reporting malignancies after HT. The proportions from each study were subjected to random effects model that yielded the pooled estimate with 95% confidence intervals (CI). Fifty-five studies comprising 60,684 HT recipients reported 7,759 total cancers during a mean follow-up of 9.8 ± 5.9 years, with an overall incidence of 15.3% (95% CI = 12.7%-18.1%). Mean time from HT to cancer diagnosis was 5.1 ± 4 years. The most frequent cancers were gastrointestinal (7.6%), skin (5.7%), and hematologic/blood (2.5%). Meta-regression showed no association between incidence of cancer and mean age at HT (coeff: -0.008; p=0.25), percentage of male recipients (coeff: -0.001; p=0.81), donor age (coeff: -0.011; p=0.44), 5-year (coeff: 0.003; p=0.12) and 10-year (coeff: 0.02; p=0.68) post-transplant survival. There is a substantial risk of malignancies in HT recipients, most marked for gastrointestinal, skin, and hematologic. Despite their occurrence, survival is not significantly impacted.

Post-Transplant Malignancies following Pancreas Transplantation: Incidence and Implications on Long-Term Outcome from a Single-Center Perspective

Chronic immunosuppression is associated with an increased risk of malignancy. The main objective of this study is to evaluate the incidence and effect of post-transplant malignancies (PTMs) following pancreas transplantation. The 348 first pancreas transplants performed between 1985 and 2015 were retrospectively analyzed in this study. Incidences of PTMs, as well as patient and graft survival, were evaluated. Out of 348 patients, 71 (20.4%) developed a PTM. Median time to diagnosis was 130 months. Thirty-six patients (50.7%) developed skin cancers (four patients with melanoma, 32 with NMSCs). Solid organ malignancy occurred in 25 (35.2%), hematologic malignancy in ten patients (14.1%). Affected patients were transplanted earlier [2000 (IQR 1993−2004) vs. 2003 (IQR 1999−2008); p < 0.001]. No differences in induction therapy were seen, both groups demonstrated comparable patient and graft survival. Pancreas transplant recipients with solid organ and hematologic malignancies had a three- and six-fold increased hazard of death compared to those with skin cancers [aHR 3.04 (IQR 1.17–7.91); p = 0.023; aHR 6.07 (IQR 1.87–19.71); p = 0.003]. PTMs affect every fifth patient following pancreas transplantation. Skin cancers are the most common malignancies accounting for 50% of all PTMs. These results underscore the importance of close dermatologic follow-up.

Review of Outcomes after Diagnosis of Malignancy in Kidney Transplant Patients: UNOS Database

Malignancy is the third major cause of death among transplant recipients. Patient and kidney transplant outcomes after the diagnosis of malignancy are not well described. We reviewed incidences and outcomes of colorectal, lung, PTLD, and renal malignancy after transplant among patients who received a transplant from January 2000 to December 2018 using the UNOS/OPTN database. Incidence of each malignancy was measured at 5 years and 10 years of transplant. The Kaplan–Meier curve was used for time-to-event analysis (graft and patient outcomes). Additionally, we sought to identify the causes of graft failure among these recipients. We found that 12,764 (5.5%) patients suffered malignancy, excluding squamous and basal cell skin carcinoma after transplant. During the first 5 years of transplant, incidence of colorectal, lung, PTLD, and renal malignancies was 2.99, 9.21, 15.61, and 8.55 per 10,000 person-years, respectively. Rates of graft failure were 10.3%, 7.6%, 19.9%, and 18.8%, respectively, among these patients at 5 years. Mortality rate was highest among patients who suffered lung malignancy (84%), followed by colorectal (61.5%), PTLD (49.1%), and renal (35.5%) at 5 years after diagnosis of malignancy. In conclusion, kidney transplant recipients diagnosed with lung malignancy have the lowest graft survival, compared to PTLD, colorectal, and renal malignancy. PTLD has the highest incidence rate in the first 5 years of transplant.

Rapamycin Inhibitors for Eye Squamous Cell Carcinoma after Renal Transplantation: A Case Report

INTRODUCTION

The immunosuppressive efficiency obtained in the last decades in kidney transplantation significantly improved graft survival. However, there is still a high risk and incidence of cancer in transplant patients strongly and directly related to the type of immunosuppression. An increasing body of evidence suggests that the PI3K/Akt/mTOR pathway may play a pivotal role in the development and progression of several neoplastic diseases.

CASE PRESENTATION

We describe a 47-year-old male patient who received a cadaveric primary renal transplant in November 2008 developing a poorly differentiated infiltrating and ulcerated squamous cell carcinoma (SCC) at the eye level. In this patient, the modification of an immunosuppressive regimen with introduction of rapamycin (mTOR) inhibitors and withdrawal of calcineurin inhibitors (CNIs) led to the resolution of this severe condition.

CONCLUSION

The introduction of mTOR inhibitors and withdrawal of CNIs in kidney-transplanted patients with de novo eye SCC should be considered in this clinical setting.

Colorectal Surgery in Kidney Transplant Recipients: A Decade of Trends and Outcomes in the United States

There is paucity of data evaluating the trends and outcomes of colorectal surgery (CRS) in kidney transplant recipients (KTRs). Using the Nationwide Inpatient Sample 2001 to 2010, a retrospective review of CRS performed in KTRs was performed. Trends, demographics, indications, and outcomes were examined for elective and emergent cases and compared with the general population (GP) on multivariate logistic regression. A total of 2616 KTRs underwent CRS, 50 per cent of which were done emergently. KTRs developed colon and rectal cancer at a younger age and had significantly higher incidence of comorbidities compared with the GP. Diverticular disease was the most common indication for surgery (48%) followed by cancer (30.6%). Compared with the GP, KTRs had higher rates of mortality (6.29 vs 3.64%), wound complications (8.02 vs 5.37%), and acute renal failure (ARF) (17.14 vs 7.10%) (all P < 0.05). No difference was seen in the incidence of anastomotic leak. On multivariate analysis, KTRs had higher associated odds of ARF (odds ratio, 2.02; P < 0.001), whereas the odds of mortality, wound, and anastomotic complications were similar to the GP. Emergency surgery in KTRs was associated with worse outcomes compared with the elective setting. KTRs undergoing CRS have unique characteristics that are different than the GP. They are at an increased risk of complications, especially acute renal failure.

An update on cancer after kidney transplantation

The emergence of onconephrology in recent years highlights the importance of the interaction between kidney disease and cancer. Chronic kidney disease (CKD) and cancer are linked with each other in different ways bidirectionally: cancer can cause CKD, whereas CKD itself may be a risk factor for cancer. Kidney transplant recipients (KTRs) have a 2- to 3-fold increased cancer risk when compared with the general population. The elevated risk covers a wide range of cancers. Some are related to CKD, including cancers of the kidney, urinary tract and thyroid, whereas others are related to oncogenic viruses that include non-Hodgkin lymphoma, cervical cancer, nonmelanoma skin cancer and Kaposi's sarcoma. There is no standard protocol regarding how immunosuppressive drugs should be adjusted in patients who develop posttransplant cancers. However, any modification of immunosuppressive regimens should be balanced against the risk of allograft rejection or deterioration in kidney function. Cancer surveillance can be used as a strategy to improve the clinical outcome in KTRs. Although guidelines adopted in the general population have been used as the reference, a personalized approach based on individual cancer risk, life expectancy and concurrent comorbidities has to be adopted.

Proton Therapy in the Treatment of Anal Cancer in Pelvic Kidney Transplant Recipients: A Case Series

PURPOSE

The incidence of anal cancer in patients with kidney transplants has increased. The definitive treatment for anal cancer is chemotherapy and intensity-modulated radiation therapy. In kidney transplant recipients, sparing the pelvic kidney in the process of delivering radiation to the anus can be challenging. Intensity-modulated proton therapy (IMPT) has been proposed as an alternative to intensity-modulated radiation therapy for the treatment of anal cancer in this population, given its increased ability to spare organs-at-risk.

CASE SERIES

We present 4 cases of patients with transplanted pelvic kidneys who subsequently developed anal cancer and were treated with IMPT from 2017 to 2019.

CONCLUSION

Use of IMPT appears to be an acceptable option for the treatment of anal cancer in patients with a pelvic kidney.

Polygenic risk score as a determinant of risk of non-melanoma skin cancer in a European-descent renal transplant cohort

Renal transplant recipients have an increased risk of non-melanoma skin cancer (NMSC) compared to in the general population. Here, we show polygenic risk scores (PRS) calculated from genome-wide association studies (GWAS) of NMSC in a general, nontransplant setting, can predict risk of, and time to posttransplant skin cancer. Genetic variants, reaching predefined P-value thresholds were chosen from published squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) nontransplant GWAS. Using these GWAS, BCC and SCC PRS were calculated for each sample across three European ancestry renal transplant cohorts (n = 889) and tested as predictors of case:control status and time to NMSC posttransplant. BCC PRS calculated at P-value threshold 1 × 10-5 was the most significant predictor of case:control status of NMSC posttransplant (OR = 1.61; adjusted P = .0022; AUC [full model adjusted for clinical predictors and PRS] = 0.81). SCC PRS at P-value threshold 1 × 10-5 was the most significant predictor of time to posttransplant NMSC (adjusted P = 9.39 × 10-7 ; HR = 1.41, concordance [full model] = 0.74). PRS of nontransplant NMSC is predictive of case:control status and time to NMSC posttransplant. These results are relevant to how genomics can risk stratify patients to help develop personalized treatment regimens.

Complications of Cardiac Transplantation

PURPOSE OF REVIEW

Despite the improvement in medical therapy for heart failure and the advancements in mechanical circulatory support, heart transplantation (HT) still remains the best therapeutic option to improve survival and quality of life in patients with advanced heart failure. Nevertheless, HT recipients are exposed to the risk of several potential complications that may impair their outcomes. In this article, we aim to provide a practical and scholarly framework for clinicians approaching heart transplant medicine, as well as a concise update for the experienced readers on the most relevant post-HT complications.

RECENT FINDINGS

While recognizing that most of the treatments herein discussed are based more on experience than on solid scientific evidence, significant step forward has been made in particular in the recognition and management of primary graft dysfunction, antibody-mediated rejection, and renal dysfunction. Complications after HT may vary according to the time from surgery and can be related to graft function and pathology or to diseases and dysfunctions occurring in other organs or systems, mainly as side effects of immunosuppressive drugs and progression of pre-existing conditions. Future research needs to focus on improving precision diagnostics of causes of graft dysfunction and on reaching an optimal and customized balance between efficacy and toxicities of immunosuppressive strategies.

Rare skeletal muscle metastasis from renal cell carcinoma: case report and review of the literature

Renal cell carcinoma (RCC) is a tumor that usually metastasizes to lung, liver, bone and brain, but rarely to skeletal muscles. We report a case of an elderly man with a history of bilateral metachronous RCC for which he underwent curative bilateral nephrectomies and renal transplantation, was in remission, and presented with a large solitary skeletal muscle metastasis from the initial RCC, 3 years later.

Urothelial carcinoma of an allograft ureter 10 years after deceased donor kidney transplantation

The incidence of urothelial carcinoma (UC; formerly transitional cell carcinoma) is higher among renal transplant recipients compared with the general population. Upper urinary tract UC (UUT-UC) of allograft urothelium is a rare event with approximately 40 cases reported in the literature. Herein, we describe the clinical presentation and management of UUT-UC in a transplant ureter 10 years after deceased donor kidney transplantation.

Role of Cytomegalovirus and Epstein-Barr virus in Patients with de Novo Colon Cancer after Renal Transplantation

Aims

The development of new effective immunosuppressive agents has provided long-term survival for transplant recipients, thereby increasing the risk of de novo malignancy in chronic immunocompromised hosts. Although de novo post-transplant lymphoproliferative diseases and skin cancer have been shown to have an increased incidence in long-term surviving solid organ transplant recipients, the association with colon cancer is controversial.

Patients and methods

Over a 12-year period, 20 patients (5%) out of 400 renal transplant recipients (treated at the University Hospitals of Udine and Ancona) developed 24 de novo tumors; 11 skin cancers and 13 non-skin cancers. Three patients developed de novo colon cancer. Immunosuppressive therapy was reduced immediately after diagnosis, and all patients were shifted from cyclosporine to rapamicine within 30 days. The tumor was surgically resected with curative intent in 2 cases, and 1 patient had only palliative surgery due to metastatic disease. The postoperative course was uneventful, and all patients maintained normal graft function.

Results

Two of 3 patients died of progression of the neoplasm, within a median time from the diagnosis of 12 months. We analyzed the possible correlations between de novo colon cancer and “serology (hepatitis C virus-hepatitis B virus, HCV-HBV) status'’ infections, cytomegalovirus and Epstein-Barr virus reactivation, episodes of rejection, and blood transfusions.

Conclusions

Differently from other de novo skin and non-skin tumors, our cases developed cytomegalovirus and Epstein-Barr virus reactivation within 3 months of transplantation. Therefore, we suggest a closer follow-up for de novo colon cancer in renal transplants with early cytomegalovirus and Epstein-Barr virus reactivation in order to avoid a delay in diagnosis.

Carcinoma of the Tongue in Renal Transplant Recipients: An Unusual Spectrum of De novo Malignancy at a Tertiary Care Center in India Over a Period of 26 Years

Renal transplant recipients are at a higher risk of malignancy. We report our experience and the critical differences in the presentation of malignancy in kidney transplant patients performed at our tertiary care center and followed up over the period of 1990–2015. A total of 338 live donor transplants performed in 332 patients were analyzed. Induction immunosuppression was used in 22 cases with interleukin-2 (IL-2) receptor antibody. Overall 299 patients were continued on calcineurin inhibitor (CNI)-based triple drug immunosuppression, 33 were off CNI with 13 of them receiving sirolimus additionally. A total of 16 malignancies including post transplant lymphoproliferative disease (5), oral cancer (5), lung cancer (2), hepatobiliary cancer (2), colon cancer (1), and skin cancer (1) were diagnosed in 15 patients. Over the 26-year follow up, 138 patients died of whom 12 died due to cancer. Cancer occurred in 4.7% of patients but accounted for 9.4% of deaths. Oral cancer occurred after a significantly longer latency of over 10 years (212 vs. 94 months, P = 0.00652). Despite the longer latency, oral cancer patients were younger at diagnosis (44.0 vs. 52 years, P = 0.01016) and had better outcome (Fisher's exact test, P = 0.0275). This was despite a longer overall follow-up for the oral cancer patients, reflecting the better outcome for these patients (24 vs. 4 months, P = 0.0278). This might be the result of relatively early diagnosis of oral cancers.

Treatment options and predictive factors for recurrence and cancer-specific mortality in bladder cancer after renal transplantation: A multi-institutional analysis

OBJECTIVES

Bladder cancer (BC) in the transplanted population can represent a challenge owing to the immunosuppressed state of patients and the higher rate of comorbidities. The objective was to analyze the treatment of BC after renal transplant (RT), focusing on the mode of presentation, diagnosis, treatment options and predictive factors for recurrence.

MATERIAL AND METHODS

We conducted an observational prospective study with a retrospective analysis of 88 patients with BC after RT at 10 European centers. Clinical and oncologic data were collected, and indications and results of adjuvant treatment reviewed. The Kaplan-Meier method and uni- and multivariate Cox regression analyses were performed.

RESULTS

A total of 10,000 RTs were performed. Diagnosis of BC occurred at a median of 73 months after RT. Median follow-up was 126 months. Seventy-one patients (81.6%) had non-muscle invasive bladder cancer, of whom 29 (40.8%) received adjuvant treatment; of these, six (20.6%) received bacillus Calmette-Guérin and 20 (68.9%) mitomycin C. At univariate analysis, patients who received bacillus Calmette-Guérin had a significantly lower recurrence rate (P=.043). At multivariate analysis, a switch from immunosuppression to mTOR inhibitors significantly reduced the risk of recurrence (HR 0.24, 95% CI: 0.053-0.997, P=.049) while presence of multiple tumors increased it (HR 6.31, 95% CI: 1.78-22.3, P=.004). Globally, 26 patients (29.88%) underwent cystectomy. No major complications were recorded. Overall mortality (OM) was 32.2% (28 patients); the cancer-specific mortality was 13.8%.

CONCLUSIONS

Adjuvant bacillus Calmette-Guérin significantly reduces the risk of recurrence, as does switch to mTOR inhibitors. Multiple tumors increase the risk.

HPV type 45-positive condyloma acuminata of the bladder in a renal transplant recipient

Condyloma acuminata (CA) are warty lesions caused by human papilloma virus (HPV) that generally affect the external genitalia and mucocutaneous junctions. Involvement of the urinary tract is rare, and involvement of the urinary bladder is thought to be due to immunosuppression. A 30-year-old woman was diagnosed with urethral CA 12 months after renal transplantation. She underwent transurethral resection (TUR) of the urethral lesions. During the operation, multiple sessile warty lesions were found incidentally inside the bladder and were also removed by TUR. The patient's postoperative course was uneventful. Pathological examination confirmed that the lesions were CA. Multiplex real-time polymerase chain reaction was performed to confirm the HPV genotype and revealed type 45 HPV DNA. CA of the urethra are uncommon, and bladder involvement is extremely rare. This case is the first reported, to our knowledge, to involve HPV type 45 in bladder condyloma. TUR may be the preferred option for the management of CA in the urinary bladder.

Azathioprine and Risk of Skin Cancer in Organ Transplant Recipients: Systematic Review and Meta-Analysis

Azathioprine, a purine antimetabolite immunosuppressant, photosensitizes the skin and causes the production of mutagenic reactive oxygen species. It is postulated to increase the risk of squamous cell carcinoma (SCC) and other skin cancers in organ transplant recipients (OTRs), but evidence from multiple, largely single-center studies to date has been inconsistent. We aimed to resolve the issue of azathioprine's carcinogenicity by conducting a systematic review of the relevant literature and pooling published risk estimates to evaluate the risks of SCC, basal cell carcinoma (BCC), keratinocyte cancers (KCs) overall and other skin cancers in relation to azathioprine treatment. Twenty-seven studies were included in total, with risk estimates from 13 of these studies able to be pooled for quantitative analysis. The overall summary estimate showed a significantly increased risk of SCC in relation to azathioprine exposure (1.56, 95% confidence interval [CI] 1.11-2.18). No significant associations between azathioprine treatment and BCC (0.96, 95% CI 0.66-1.40) or KC (0.84, 95% CI 0.59-1.21) risk were observed. There was significant heterogeneity between studies for azathioprine risk estimates and the outcomes of SCC, BCC and KC. The pooled findings of available evidence support the contention that treatment with azathioprine increases the risk of SCC in OTRs.

Cancer Screening of Renal Transplant Patients Undergoing Long-Term Immunosuppressive Therapy

OBJECTIVE

With this study we aimed to research the effects of immunosuppressive drugs, their cumulative doses, and viral infections on development of malign tumors in patients who have undergone treatment for 5 years.

METHODS

We examined 100 patients who underwent renal transplantation from 2004 to 2009. Patients had mycophenolate mofetil and steroid in addition to cyclosporine, sirolimus, or tacrolimus as immunosuppressive treatment. For malignancy screening, physical examination, radiologic and endoscopic screening were done, and immunosuppressive drugs and their cumulative doses, age, sex, body mass index (BMI), dialysis history, and viral infection history were investigated.

RESULTS

The mean age of patients was 42.03 ± 11.30 years. There were 1 colon cancer patient, 1 retroperitoneal liposarcoma, 1 renal oncocytoma, 3 Kaposi sarcoma patients treated with cyclosporine; in those treated with Tac there were 1 basal cell carcinoma, 1 Kaposi sarcoma, 2 thyroid carcinoma, 1 breast carcinoma, 1 bladder carcinoma, 1 renal cell carcinoma, and 1 colon carcinoma patients. The mean age of patients having carcinoma was statistically significant compared with those without cancer (P < .01). The prednisolone cumulative dose was significantly higher in carcinoma patients than in patients without carcinoma (P < .01).

RESULTS

The use of long-term chronic immunosuppressive therapy may increase the development of cancer. The risk of carcinoma increases with increasing drug dose and time period of the immunosuppressive drug. There was not a negative effect on cancer prevalence in patients with cyclosporine or tacrolimus. But the cumulative dose of steroids significantly increased malignancy occurence.

Management and prevention of post-transplant malignancies in kidney transplant recipients

The central issue in organ transplantation remains suppression of allograft rejection. Thus, the development of immunosuppressive drugs has been the key to successful allograft function. The increased immunosuppressive efficiency obtained in the last two decades in kidney transplantation dramatically reduced the incidence of acute rejection. However, the inevitable trade-off was an increased rate of post-transplant infections and malignancies. Since the incidence of cancer in immunosuppressed transplant recipients becomes greater over time, and the introduction of new immunosuppressive strategies are expected to extend significantly allograft survival, the problem might grow exponentially in the near future. Thus, cancer is becoming a major cause of morbidity and mortality in patients otherwise successfully treated by organ transplantation. There are at least four distinct areas requiring consideration, which have a potentially serious impact on recipient outcome after transplantation: (i) the risk of transmitting a malignancy to the recipient within the donor organ; (ii) the problems of previously diagnosed and treated malignancy in the recipient; (iii) the prevention of de novo post-transplant malignant diseases and (iv) the management of these complex and often life-threatening clinical problems. In this scenario, the direct and indirect oncogenic potential of immunosuppressive therapy should be always carefully considered.

Management of Metachronous Bilateral Testis Cancer in a Patient with Pre-B Cell ALL

We present a patient with a metachronous, second testicular cancer after being diagnosed with pre-B cell ALL and receiving induction chemotherapy for a bone marrow transplant. We discuss the management of bilateral testis masses in a young patient with a hematologic malignancy as well as the role of immunosuppressive chemotherapy in developing a second cancer. This case illustrates the importance of recognizing bilateral testicular cancer early, as well as the importance of follow-up care in oncology patients including routine measurements of tumor markers. A multidisciplinary approach between medical oncology and urology, including close monitoring of the contralateral testis, remains paramount to patient care.

CTLA4 polymorphisms and de novo malignancy risk after renal transplantation in Chinese recipients

Genetic polymorphisms in cytotoxic T lymphocyte-associated antigen 4 (CTLA4) play an influential role in graft rejection and the long-term clinical outcome of organ transplantation. We investigated the association of five CTLA4 single-nucleotide polymorphisms (SNPs) (rs733618 C/T, rs4553808 A/G, rs5742909 C/T, rs231775 A/G, and rs3087243 G/A) with de novo malignancy in 1463 Chinese renal transplantation (RT) recipients who underwent a 192-month follow-up. Multivariate analyses revealed that recipient rs231775 genotype is significantly associated with tumorigenesis (P = 0.012). Multiplicative interaction between rs231775 AA and possible risk factors of malignancy revealed two significant results: rs231775 AA × primary diseases and rs231775 AA × number of HLA-mismatch. The frequency of haplotype TACAG was significantly higher in the tumor group (17.07%) than that in the nontumor group (1.53%). In addition, aristolochic acid nephropathy (P = 0.003) and the time of discovery of tumor (P = 0.000) also were independently associated with tumorigenesis. Our data show that the CTLA4 genotype rs231775 AA may be one of risk factors for the development of malignancy and haplotype TACAG was susceptible haplotype in Chinese kidney transplant recipients.

De Novo Renal Cell Carcinoma in an Allograft Kidney Treated with Nephron-Sparing Surgery: A Case Report

The development of primary malignant tumors is a distressing complication of organ transplant. However, the emergence of de novo renal cell carcinoma from a kidney allograft is rare. A 60-year-old man underwent living kidney transplant from a spousal donor. Six years after the transplant surgery, computed tomographic evaluation confirmed the presence of a 2.8-cm-diameter solid mass in the lower pole of the allograft. Partial allograft nephrectomy was performed, and the margin surrounding the normal parenchyma was resected. The serum level of creatinine did not decrease. Here, we report a case of renal cell carcinoma in an allograft kidney that was successfully treated with nephron-sparing surgery.

Prescription trends of immunosuppressive drugs in post-heart transplant recipients in Taiwan, 2000-2009

PURPOSE

Significantly increasing heart transplantations have been performed in Taiwan in the past decades, but the trends of maintenance immunosuppression for heart transplant recipients have not been well known. In this study, we aimed to explore the trends of maintenance immunosuppressive therapy and common complications for heart transplant recipients.

METHODS

We retrospectively analyzed ambulatory prescriptions in 488 heart transplant recipients for the period 2000-2009. Patient complications after heart transplantation were also identified.

RESULTS

The annual number of new heart transplant recipients ranged from 18 to 68. The 5-year survival rate was 77.9%. The total number of regimens was 10 in 2000, and increased to 28 in 2009. Most prescriptions were immunosuppressive combinations (95.5%-89.5%). The majority of immunosuppressive regimens were a triple regimen: cyclosporine, mycophenolic acid and corticosteroid in 2009. Cyclosporine was a predominant calcineurin inhibitor with a decreasing trend from 73.9% to 59.1%, whereas the use of tacrolimus significantly increased from 11.9% to 38.4%. Mycophenolic acid was the most frequently used antimetabolite (60.1%-80.3%), while the use of azathioprine was reduced (21.6%-2.3%). From 2008, the launch of everolimus initiated a new era in the utilization of mammalian target of rapamycin inhibitors for maintenance immunosuppression.

CONCLUSIONS

Cyclosporine remained the most frequently used calcineurin inhibitors, and tacrolimus increased gradually. Mycophenolic acid was the most popular antimetabolite rather than azathioprine. The rapidly increased everolimus combined regimen may change the patterns of maintenance immunosuppression. The increasing number of combination therapies indicates an active role of everolimus and a tendency of complex tailored individual therapies.

Neoplasm incidence in simultaneous pancreas and kidney transplantation: a single-center analysis

BACKGROUND

Long-term immunosuppression is associated with an increased rate of cancer. The aim of this study was to analyze the incidence of newly diagnosed tumors in simultaneous kidney and pancreas transplantation (SPKT).

METHODS

We retrospectively analyzed the incidence of a neoplasm among 360 diabetic subjects who consecutively underwent SPKT from 1985 to August 2010 in a single institution. Data were retrieved from the institutional registry. We evaluated the nature of all newly diagnosed malignant tumors, including posttransplantation lymphoproliferative disease (PTLD), to compare Kaplan-Meier survival rates with those of patients free of a neoplasm.

RESULTS

The median follow-up was 8 years; the overall 5-year patient survival was 84%. In 25 patients the tumors were malignant. Almost one-fourth of the cancers represented skin tumors (3 squamous cell and 4 basal cell carcinomas). PTLD was diagnosed in 5 recipients. The cumulative survival of patients with malignancies was significantly lower than that in recipients without cancer (8-year survival by 38% vs 70%; P < .001). The mean (±SD) time to diagnosis was 6 ± 3 years. Since 2004, the 12 recipients with malignancy who were switched to sirolimus at the time of diagnosis showed survivals that were not apparently better than those who remained on the established immunosuppression (46% vs 55%; P = .71).

CONCLUSIONS

The risk of neoplasm development was similar to that reported by other centers. Recipients of SPKT show higher incidence of cancer, though their overall survival is still significantly better than in those usually remaining on dialysis.

Cancer stem cell immunology: key to understanding tumorigenesis and tumor immune escape?

Cancer stem cell (CSC) biology and tumor immunology have shaped our understanding of tumorigenesis. However, we still do not fully understand why tumors can be contained but not eliminated by the immune system and whether rare CSCs are required for tumor propagation.

Long latency or recurrence periods have been described for most tumors. Conceptually, this requires a subset of malignant cells which is capable of initiating tumors, but is neither eliminated by immune cells nor able to grow straight into overt tumors. These criteria would be fulfilled by CSCs. Stem cells are pluripotent, immune-privileged, and long-living, but depend on specialized niches. Thus, latent tumors may be maintained by a niche-constrained reservoir of long-living CSCs that are exempt from immunosurveillance while niche-independent and more immunogenic daughter cells are constantly eliminated.

The small subpopulation of CSCs is often held responsible for tumor initiation, metastasis, and recurrence. Experimentally, this hypothesis was supported by the observation that only this subset can propagate tumors in non-obese diabetic/scid mice, which lack T and B cells. Yet, the concept was challenged when an unexpectedly large proportion of melanoma cells were found to be capable of seeding complex tumors in mice which further lack NK cells. Moreover, the link between stem cell-like properties and tumorigenicity was not sustained in these highly immunodeficient animals. In humans, however, tumor-propagating cells must also escape from immune-mediated destruction. The ability to persist and to initiate neoplastic growth in the presence of immunosurveillance – which would be lost in a maximally immunodeficient animal model – could hence be a decisive criterion for CSCs.

Consequently, integrating scientific insight from stem cell biology and tumor immunology to build a new concept of “CSC immunology” may help to reconcile the outlined contradictions and to improve our understanding of tumorigenesis.

CD86 is an activation receptor for NK cell cytotoxicity against tumor cells

CTLA4Ig has been successfully used in the clinic for suppression of T cell activation. However, patients treated with CTLA4Ig experienced reduced incidence of tumors than predicted, but the underlying mechanism remains unknown. In this paper, we showed that brief administration of CTLA4Ig significantly reduced tumor metastasis and prolonged the survival of host mice bearing B16 melanoma. Depletion of NK cells prior to CTLA4Ig administration eliminated the CTLA4Ig-mediated anti-tumor activity. CTLA4Ig enhanced NK cell cytotoxicity to tumor cells via up-regulation of NK cell effecter molecules CD107a and perforin in vivo. In addition, we demonstrated that, upon activation, NK cells could significantly increase the expression of CD86 both in vitro and in vivo, and ligation of CD86 with CTLA4Ig significantly increased the ability of NK cells to kill tumor cells. Furthermore, a human NK cell line that expressed high level of CD86 was directly activated by CTLA4Ig so that killing of tumor targets was enhanced; this enhanced killing could be inhibited by blocking CD86. Our findings uncover a novel function of CTLA4Ig in tumor immunity and suggest that CD86 on NK cells is an activating receptor and closely involved in the CTLA4Ig-mediated anti-tumor response.

The high rate of de novo graft carcinomas in renal transplant recipients

BACKGROUND

To investigate the incidence, the clinical characteristics and outcomes of renal graft carcinomas in the same renal transplant population.

METHODS

From April 1989 to April 2012, 1,037 consecutive renal transplantations were performed in our department. Data were collected prospectively in an extensively maintained database. For all recipients, monitoring consisted of clinical examination and an abdominopelvic CT scan or ultrasonography at least once a year.

RESULTS

After 1,037 renal transplantations, 48 men and 14 women (sex ratio 3:4) with a mean age of 54 years (25.1-78.9) were included for urological malignancies. Eight graft carcinomas were identified: 7 renal cell carcinomas (5 papillary carcinomas and 2 clear cell carcinomas of the renal graft) and 1 transitional cell carcinoma of the ureteral graft (incidence 0.78%). Nephron-sparing surgery was chosen for 5 patients with good outcomes. All graft renal cell carcinomas were classified as pT1a and the mean size of tumors was 28.4 mm (range 6-45). The 5-year specific survival rate was 100%. No recurrence was observed with a mean follow-up of 36.8 months (4.1-84.3).

CONCLUSION

Thus confirming an increased risk of de novo graft cancer, close monitoring of renal transplant recipients should be discussed with at least an abdominopelvic ultrasonography and PSA measurement once a year. Renal cell graft carcinomas seemed to be mostly small and of papillary type and low grade.

De novo malignancies in renal transplant recipients: experience at a single center with 1882 transplant patients over 39 yr

PURPOSE

Cancers complicating organ allografts are a major cause of morbidity and mortality after renal transplantation. Different registries have described an overall three to eightfold increase in cancer risk compared with the general population. This retrospective study investigated the incidence and outcome of de novo malignancies following kidney transplantation in a single German kidney transplantation center.

MATERIALS AND METHODS

Between 1966 and 2005, 1882 patients underwent kidney transplantation at the Erlangen-Nuremberg kidney transplantation center. The incidence and types of post-transplant malignancies were retrospectively analyzed according to the patients' records and the database of the local cancer registry.

RESULTS

We identified 257 malignancies in 231 patients, an overall incidence of 13.7%. The mean follow-up time was 9.9 yr (range, 0.4-25.5 yr). The observed incidence data corresponded to a 12.1-fold increase in the overall risk of developing a malignant nonskin tumor compared with the nontransplanted population. Urinary tract malignancies represented the most frequent malignancies among the nonskin tumors (32.1%), followed by gastrointestinal tract (30.7%) and gynecological (14%) cancers. When we considered the duration from renal transplantation to tumor detection and tumor-specific survival, there was no difference between patients treated with or without a cyclosporine A-based regimen.

CONCLUSIONS

In our study, the overall risk of developing a post-transplant nonskin malignancy was 12.1-fold higher compared with the age-matched general population. Development of solid organ malignancies is one of the most frequent causes of morbidity and mortality in renal transplant recipients; thus, close tumor screening in patients after kidney transplantations is warranted.

Systematic review of hepatocellular carcinoma mortality rates among hepatitis B virus-infected renal transplant recipients, with supplemental analyses of liver failure and all-cause mortality

OBJECTIVES

The purpose of this review was to compare the mortality rates for hepatocellular carcinoma (HCC) among hepatitis B surface antigen (HBsAg)-seropositive renal transplant (RT) patients versus HBsAg-seropositive persons of the general population.

METHODS

A comprehensive search was performed to identify cohort studies of HBsAg-seropositive RT patients with at least 4 years of follow-up. Data were analyzed as outlined below. HCC was a rare event in regions of low and intermediate seroprevalence of HBsAg. Subsequently, studies from low and intermediate seroprevalence areas were analyzed separately from those of high seroprevalence areas.

RESULTS

Thirty-one retrospective studies that followed 1277 seropositive RT patients were identified for inclusion. The studies were pooled and compared to four different general population studies that included 12558 seropositive persons using Poisson methods. The mortality rate of HCC was increased in low and intermediate seroprevalence areas (RR 7.67, 95% confidence interval (CI) 3.93-15.0; RR 9.92, 95% CI 5.38-18.3). In high seroprevalence areas, the mortality rate of HCC was increased compared to one population study, but not another (RR 2.76, 95% CI 1.64-4.63; RR 1.02, 95% CI 0.61-1.69).

CONCLUSIONS

Mortality due to HCC was increased in low and intermediate seroprevalence areas, but the evidence was inconclusive for high seroprevalence areas.

Calcineurin inhibitors and immunosuppression - a tale of two isoforms

Organ transplantation is the state of the art for treating end-stage organ failure. Over 25000 organ transplants are performed in the USA each year. Survival rates following transplantation are now approaching 90% for 1 year and 75% for 5 years. Central to this success was the introduction of drugs that suppress the immune system and prevent rejection. The most commonly used class of immunosuppressing drugs are calcineurin inhibitors (CNIs). Calcineurin is a ubiquitous enzyme that is important for T-cell function. With more people taking CNIs for longer and longer periods of time the consequences of calcineurin inhibition on other organ systems - particularly the kidney - have become a growing concern. Virtually all people who take a CNI will develop some degree of kidney toxicity and up to 10% will progress to kidney failure. In the past 15 years, research into calcineurin action has identified distinct actions of the two main isoforms of the catalytic subunit of the enzyme. The α-isoform is required for kidney function whereas the β-isoform has a predominant role in the immune system. This review will discuss the current state of knowledge about calcineurin isoforms and how these new insights may reshape post-transplant immunosuppression.

Effects of chronic immunosuppression on long-term oncologic outcomes for colorectal cancer patients undergoing surgery

INTRODUCTION

The effects of chronic immunosuppressive therapy (CIST) on long-term oncologic outcomes for patients who undergo surgery for colorectal cancer are not known. We investigate whether CIST affects these outcomes.

METHODS

From a prospective colorectal cancer database, patients undergoing colorectal resection for cancer between 1996 and 2005 and on CIST (steroids and/or cyclosporine, azathioprine, 6-mercaptopurine, FK-506, methotrexate) were identified and compared with a control group matched for age(±5 year), gender, type, and year (±2 year) of operation; American Society of Anesthesiology score; cancer stage; differentiation; vascular invasion; blood transfusion; and postoperative adjuvant therapy. The groups were compared for early and long-term outcomes. Cox models produced hazard ratios and Wald P values to assess associations between survival and the presence of immunosuppressive treatment.

RESULTS

Fifty-five (20 female and 35 male) patients were on CIST for inflammatory disease, transplantation, chronic obstructive lung disease, other cancers, and hypopituitarism. Both groups were comparable for the matched characteristics. Chronic immunosuppressive therapy and control groups had similar overall postoperative morbidity (36.4% vs 27.3%, P = 0.3) and wound infection rates (14.5% vs 5.5%, P = 0.13). Chronic immunosuppressive therapy group had significantly lower 3- and 5-year overall (49.1% vs 76.3%, and 45.1% vs 66.2%, respectively, P = 0.003) and disease-free survival (45.5% vs 69.1%, and 41.7% vs 63.3%, respectively, P = 0.005) than the control group. Local recurrence was similar between groups.

CONCLUSION

Patients on chronic immunosuppression tolerate colorectal cancer resection but have significantly worse long-term oncologic outcomes.These findings need careful consideration when evaluating the relative roles of the various treatment modalities for this group of patients presenting with colorectal cancer.

Proliferation signal inhibitors and post-transplant malignancies in heart transplantation: practical clinical management questions

Although malignancy is a major threat to long-term survival of heart transplant (HT) recipients, clear strategies to manage immunosuppression in these patients are lacking. Several lines of evidences support the hypothesis of an anticancer effect of proliferation signal inhibitors (PSIs: mammalian target of rapamycin [mTOR] inhibitors) in HT recipients. This property may arise from PSI's ability to replace immunosuppressive therapies that promote cancer progression, such as calcineurin inhibitors or azathioprine, and/or through their direct biological actions in preventing tumor development and progression. Given the lack of randomized studies specifically exploring these issues in the transplant setting, a collaborative group reviewed current literature and personal clinical experience to reach a consensus aimed to provide practical guidance for the clinical conduct in HT recipients with malignancy, or at high risk of malignancy, with a special focus on advice relevant to potential role of PSIs.

Association between chronic hepatitis C infection and coronary flow reserve in dialysis patients with failed renal allografts

BACKGROUND

Hepatitis C infection occurs frequently among patients with end-stage renal disease and increases the risk of atherosclerotic cardiovascular diseases. Endothelial dysfunction (ED) is an early event in the pathogenesis of atherosclerosis. It has been reported among patients treated with hemodialysis (HD), peritoneal dialysis (PD), or renal transplantation. The aim of the present study was to evaluate effects of chronic hepatitis C infection on ED in patients with failed renal transplants.

METHODS

Twenty-six nondiabetic, anti-hepatitis C virus (HCV)-positive (15 females, mean age: 38 +/- 8 years) and 26 anti-HCV-negative patients (15 females, mean age: 36 +/- 5 years), all of whom had returned to PD or HD after renal transplant failure were studied to assess coronary flow reserve (CFR) by transthoracic Doppler echocardiography. Serum high-sensitivity C-reactive protein (hs-CRP) levels were measured as markers of chronic inflammation. CFR recordings and intima-media thickness measurements were performed using the Vivid 7 echocardiography device.

RESULTS

Demographic and clinical characteristics of patients were similar between the two groups. Serum hs-CRP levels were significantly higher among HCV-positive patients versus HCV-negative counterparts. HCV-positive patients showed lower CFR measurement than HCV-negative ones. Also, a negative correlation was observed between serum hs-CRP levels and CFR values.

CONCLUSION

CFR values are worse among anti-HCV-positive patients with failed renal transplants compared with anti-HCV-negative subjects. Graft dysfunction per se may aggravate a proinflammatory states thereby inducing ED. Furthermore, the presence of HCV is a greater trigger of ED among patients with renal failed grafts.

Primary dedifferentiated chondrosarcoma of the lung

Extraskeletal dedifferentiated chondrosarcomas (DC) are uncommon tumors that predominantly occur in the head and neck. Herein, we describe a case of pulmonary DC detected in a patient with systemic sclerosis and presenting with a symptomatic large pleural effusion and a pulmonary lobar consolidation on chest imaging. To the best of our knowledge, this is the first report of pulmonary chondrosarcoma involving the pleura and occurring in association with systemic sclerosis. Moreover, this is the second report of a dedifferentiated variant among all reported cases of primary lung chondrosarcoma.

Minimizing the risk of posttransplant malignancy

Recent improvements in immunosuppressive therapies have reduced the incidence of acute rejection and increased patient survival. These agents may however contribute to higher rates of mortality due to an increased risk of cardiovascular disease or malignancy. Transplant patients are immunocompromised with a reduced ability to combat the development of malignancy. The higher risk for the activity of oncoviruses may also contribute to the higher incidence and determine specific tumor types. Some immunosuppressants seem to have direct oncogenic effects. In vitro data have demonstrated that calcineurin inhibitors (CNIs) may show direct effects on tumor growth and the development of metastases. In contrast, mTOR inhibitors have demonstrated anti-tumoral properties in vitro and perhaps potent anti-angiogenic effects thereby. Recent studies and registry analyses have confirmed that mTOR inhibitors are associated with a reduced incidence of malignancies. UNOS data demonstrated that an mTOR inhibitor, with or without a CNI, is associated with a reduced incidence of tumors compared to regimens without mTOR inhibitors. The Rapamune Maintenance Regimen study demonstrated that patients receiving sirolimus-based, CNI-free therapy after CsA withdrawal at 3 months showed a reduced incidence of malignancy at 5 years posttransplant, compared with those who continued on a regimen that included CsA. In the CONVERT study, patients converted to sirolimus revealed a significantly lower malignancy rate at 24 months (3.1%) compared with those who continued CNI-based therapy (9.8%, P < .001). The elimination of CNIs and the introduction of sirolimus may, therefore, have a role to reduce the risk of cancer among posttransplant patients.

Minimizing the risk of posttransplant malignancy

Nowadays cancer represents the second main cause of death in renal transplant patients with normal function of the graft. The incidence is 10 to 20 times higher than normal population. Calcineurin inhibitor therapy contributes to the increase in the development of neoplasia. Important evidence could bring a preventive effect of mammalian target of rapamycin in skin cancer, Kaposi's sarcoma, and renal cell carcinoma.