Malignancy after renal transplantation

Increased Risk of Malignancy with Immunosuppression: A Population-Based Analysis of Texas Medicare Beneficiaries

Immunosuppressive drugs (IMD) are widely utilized to treat many autoimmune conditions and to prevent rejection in organ transplantation. Cancer has been associated with prolonged use of IMD in transplant patients. However, no detailed, systematic analysis of the risk of cancer has been performed in patients receiving IMD for any condition and duration. We analyzed Medicare data from Texas Medicare beneficiaries, regardless of their age, between 2007 and 2018, from the Texas Cancer Registry. We analyzed the data for the risk of cancer after IMD use associated with demographic characteristics, clinical conditions, and subsequent cancer type. Of 29,196 patients who used IMD for a variety of indications, 5684 developed cancer. The risk of cancer (standardized incidence ratio) was particularly high for liver (9.10), skin (7.95), lymphoma (4.89), and kidney (4.39). Patients receiving IMD had a four fold greater likelihood of developing cancer than the general population. This risk was higher within the first 3 years of IMD utilization and in patients younger than 65 years and minorities. This study shows that patients receiving IMD for any indications have a significantly increased risk of cancer, even with short-term use. Caution is needed for IMD use; in addition, an aggressive neoplastic diagnostic screening is warranted.

Adherence to Immunosuppressive Therapies after Kidney Transplantation from a Biopsychosocial Perspective: A Cross-Sectional Study

Kidney transplantation (KT) is the best method for kidney replacement therapy (KRT) because of patient survival rates and quality of life (QoL). Nowadays, the main cause of graft loss is antibody-mediated rejection. The treatment of humoral injury is difficult with uncertain results and still not firmly established. Therefore, appropriate adherence is crucial to prolong graft and patient survival. This study aims to evaluate the association of transplant patients’ acceptance of illness, symptoms of anxiety and depression, frailty, and QoL with medication adherence in KT recipients. A total of 210 patients after KT completed the surveys. The instruments were distributed during patients’ admission at the clinic by a qualified nurse, who assisted the patients’ in completing the questionnaires. A cross-sectional study of KT recipients 9.45 ± 7.26 years after KT was performed. Patient adherence with medications was assessed using the Adherence to Refills and Medications Scale (ARMS). Explanatory variables were examined with validated instruments, such as the World Health Organization Quality of Life (WHOQoL-BREF) questionnaire, The Mini-Mental State Examination (MMSE), the Acceptance of Illness Scale (AIS), the Hospital Anxiety and Depression Scale (HADS), and the Tilburg Frailty Indicator (TFI) scale, respectively. Simple linear and multiple regression analyses demonstrated the positive correlation between acceptance of illness and adherence to immunosuppressive medications in a patient sample of KT recipients. The other important factor facilitating adherence to medications was linked with physical and environmental dimensions. On the other hand, frail kidney transplant patients were more likely to be non-adherent. In conclusion, identifying contributors to better medication adherence in immunosuppressive therapy is crucial in preventing transplant rejection or graft loss. In the kidney transplant population, the acceptance of illness, selected dimensions of QoL, and demographic variables associated with rural living and vocational education favored adherence behaviors.

De Novo Cancer Incidence after Kidney Transplantation in South Korea from 2002 to 2017

Advances in patient care and immunosuppressive drugs have improved graft survival, resulting in an increase in kidney transplantation (KT); however, persistent immunosuppression is thought to cause late occurrence of cancer. This population-based study consisted of a total of 14,842 patients whose data from the years 2002 to 2017 were collected from the National Health Information Database in South Korea. Malignancies occurred in 7.6% of the total KT patients. Prostate and thyroid cancers were the most common in males and females, respectively. From the age-adjusted incidence analysis, Kaposi’s sarcoma showed the highest standardized incidence ratio in both male and female patients. According to the linear regression model, cancer incidence in KT recipients under immunosuppressive conditions increased by approximately 0.1% each month. Patients’ age over 39 and the use of prednisolone as an initial steroid regimen were associated with increased risk of cancer development after KT. Our regression and proportional hazards models will help clinicians to predict the approximate cancer incidence risk when monitoring KT recipients. Based on the largest available national database, screening or monitoring methods for cancer detection and prevention can be established for KT patients by considering the factors involved in cancer development.

Epidemiological characteristics of cancers in patients with end-stage kidney disease: a Korean nationwide study

Patients with end-stage kidney disease (ESKD) have been reported to have an increased risk of cancer. However, the epidemiological characteristics of cancer in ESKD patients remain unclear. Therefore, this study aimed to investigate the epidemiological characteristics of cancer in ESKD patients and the differences based on the renal replacement therapy provided. Data on ESKD patients were obtained from the South Korean nationwide cohort Health Insurance Review and Assessment Service database. This study included 58,831 eligible patients of the total 813,907 patients diagnosed with ESKD between January 1, 2007 and December 31, 2017. Of the 58,831 ESKD patients, 3292 (5.6%) were newly diagnosed with cancer. The average duration between the diagnosis of ESKD and cancer was 3.3 ± 1.9 years (mean ± standard deviation), with no differences between hemodialysis, peritoneal dialysis, and kidney transplant groups. The most commonly observed cancer sites in ESKD patients were the colorectum, lung, and liver. The incidence of cancer increased progressively among patients undergoing kidney transplant, peritoneal dialysis, and hemodialysis in that order. Hemodialysis patients were found to have an increased risk of digestive tract cancer compared with kidney transplant patients (adjusted hazard ratio = 1.9; 95% confidence interval: 1.31-2.81; P < 0.001). The study findings may be a useful reference for cancer-screening guidelines.

Role for contrast-enhanced ultrasound in assessing complications after kidney transplant

Kidney transplantation (KT) is an effective treatment for end-stage renal disease. Despite their rate has reduced over time, post-transplant complications still represent a major clinical problem because of the associated risk of graft failure and loss. Thus, post-KT complications should be diagnosed and treated promptly. Imaging plays a pivotal role in this setting. Grayscale ultrasound (US) with color Doppler analysis is the first-line imaging modality for assessing complications, although many findings lack specificity. When performed by experienced operators, contrast-enhanced US (CEUS) has been advocated as a safe and fast tool to improve the accuracy of US. Also, when performing CEUS there is potentially no need for further imaging, such as contrast-enhanced computed tomography or magnetic resonance imaging, which are often contraindicated in recipients with impaired renal function. This technique is also portable to patients' bedside, thus having the potential of maximizing the cost-effectiveness of the whole diagnostic process. Finally, the use of blood-pool contrast agents allows translating information on graft microvasculature into time-intensity curves, and in turn quantitative perfusion indexes. Quantitative analysis is under evaluation as a tool to diagnose rejection or other causes of graft dysfunction. In this paper, we review and illustrate the indications to CEUS in the post-KT setting, as well as the main CEUS findings that can help establishing the diagnosis and planning the most adequate treatment.

Imaging of Renal Transplant Complications throughout the Life of the Allograft: Comprehensive Multimodality Review

The kidney is the most commonly transplanted solid organ. Advances in surgical techniques, immunosuppression regimens, surveillance imaging, and histopathologic diagnosis of rejection have allowed prolonged graft survival times. However, the demand for kidneys continues to outgrow the available supply, and there are efforts to increase use of donor kidneys with moderate- or high-risk profiles. This highlights the importance of evaluating the renal transplant patient in the context of both donor and recipient risk factors. Radiologists play an integral role within the multidisciplinary team in care of the transplant patient at every stage of the transplant process. In the immediate postoperative period, duplex US is the modality of choice for evaluating the renal allograft. It is useful for establishing a baseline examination for comparison at future surveillance imaging. In the setting of allograft dysfunction, advanced imaging techniques including MRI or contrast-enhanced US may be useful for providing a more specific diagnosis and excluding nonrejection causes of renal dysfunction. When a pathologic diagnosis is deemed necessary to guide therapy, US-guided biopsy is a relatively low-risk, safe procedure. The range of complications of renal transplantation can be organized temporally in relation to the time since surgery and/or according to disease categories, including immunologic (rejection), surgical or iatrogenic, vascular, urinary, infectious, and neoplastic complications. The unique heterotopic location of the renal allograft in the iliac fossa predisposes it to a specific set of complications. As imaging features of infection or malignancy may be nonspecific, awareness of the patient's risk profile and time since transplantation can be used to assign the probability of a certain diagnosis and thus guide more specific diagnostic workup. It is critical to understand variations in vascular anatomy, surgical technique, and independent donor and recipient risk factors to make an accurate diagnosis and initiate appropriate treatment.^©RSNA, 2019.

Cancer and mTOR inhibitors in kidney transplantation recipients

Background

Previous studies show that mTOR inhibitors decrease the risk of cancer development after kidney transplantation. However, the effect of cumulative doses of mTOR inhibitors on cancer after kidney transplantation is not well known.

Methods

In the current study, patients were registered into a national database in Taiwan. Between year 2000 and 2013, 4,563 patients received kidney transplantation. They were divided into two groups, according to mTOR inhibitors usage. The cumulative dose of mTOR inhibitors was recorded. Patients were followed-up until de novo cancer development, death, or the end of 2014.

Results

Patients were divided into two groups: mTOR inhibitors users (study group, n = 828) and mTOR inhibitors non-users (control group, n = 3,735). The median follow-up duration was 7.8 years. The risk of de novo cancer (hazards ratio (HR) 0.80, 95% CI [0.60–1.09], p = 0.16) and risk of death (HR 1.14, 95% CI [0.82–1.60], p = 0.43) was not different between mTOR inhibitor user and non-user groups. Neither high- nor low-dose exposure to mTOR inhibitors was associated with increased risk of cancer or mortality. Analysis of cancer subtypes showed no influence by mTOR inhibitors. In addition, the cause of mortality was not significantly different between the two groups.

Discussion

We could not find the association of mTOR inhibitors use and risk of de novo cancer development or mortality in patients with kidney transplantation in Chinese patients. Cumulative exposure to mTOR inhibitors did not change the results.

Cancer risk after renal transplantation in South Korea: a nationwide population-based study

Background

This study aimed to evaluate patterns of posttransplant malignancies among renal transplant recipients (RTRs) in South Korea using nationwide data.

Methods

The nationwide cohort assessed in this study included RTRs from January 1, 2010, to December 31, 2014. We analyzed cancer incidence during the time course after renal transplantation. Additionally, we calculated standardized incidence ratios (SIRs) to evaluate the risk of malignancies in RTRs.

Results

A total of 1343 RTRs (871 males and 472 females, mean age 48.5 ± 11.6 years) were assessed. Among them, 104 (7.7%) developed malignancies after transplantation, most commonly in the thyroid cancer (23.1%). The SIR for all cancers was 3.54; particularly, the SIRs for renal cancer, myeloma, and non-Hodgkin lymphoma were 16.31, 24.02, and 28.64, respectively. Females showed a higher risk of malignancy than males (SIRs: 4.04 for women and 3.26 for men). The median interval between transplantation and malignancy diagnosis was 27.2 months (range 12.3–54.8 months).

Conclusions

RTRs in South Korea demonstrated a high risk of malignancy after transplantation compared with the general population. This indicates that close surveillance and routine screening for cancer in RTRs are needed.

Cancer risks in recipients of renal transplants: a meta-analysis of cohort studies

Renal transplantation is associated with an increased risk of cancers at multiple sites; however, the relationships between increased cancer risk and participant characteristics remain unclear. We searched PubMed, Embase, and the Cochrane Library to identify prospective observational studies performed up to July 2017. Totally 11 prospective studies reported data on 79,988 renal transplant recipients were included. Renal transplant recipients were found to display a higher risk of all cancers (standard incidence ratio [SIR]: 2.89; 95% CI: 2.13–3.91; P < 0.001), gastric cancer (SIR: 1.93; 95% CI: 1.60–2.34; P < 0.001), colon cancer (SIR: 1.85; 95% CI: 1.53–2.23; P < 0.001), pancreatic cancer (SIR: 1.53; 95% CI: 1.23–1.91; P < 0.001), hepatocellular carcinoma (SIR: 2.45; 95% CI: 1.63–3.66; P < 0.001), lung cancer (SIR: 1.68; 95% CI: 1.29–2.19; P < 0.001), thyroid cancer (SIR: 5.04; 95% CI: 3.79–6.71; P < 0.001), urinary bladder cancer (SIR: 3.52; 95% CI: 1.48–8.37; P = 0.004), renal cell cancer (SIR: 10.77; 95% CI: 6.40–18.12; P < 0.001), non-melanoma skin cancer (SIR: 12.14; 95% CI: 6.37–23.13; P < 0.001), melanoma (SIR: 2.48; 95% CI: 1.08–5.67; P = 0.032), Hodgkin's lymphoma (SIR: 4.90; 95% CI: 3.09–7.78; P < 0.001), non-Hodgkin lymphoma (SIR: 10.66; 95% CI: 8.54–13.31; P < 0.001), lip cancer (SIR: 29.45; 95% CI: 17.85–48.59; P < 0.001), breast cancer (SIR: 1.11; 95% CI: 1.00–1.24; P = 0.046), and ovarian cancer (SIR: 1.60; 95% CI: 1.23–2.07; P < 0.001). However, renal transplantation did not significantly influence the risks of uterine cancer (P = 0.171), and prostate cancers (P = 0.188). Our findings suggest that patients who receive renal transplantation have an increased risk of cancer at most sites, apart from uterine and prostate cancers patients.

Squamous Cell Carcinoma of Skin after 20 Years of Renal Transplantation

Solid organ transplant recipients are at high risk of developing malignancies due to the prolonged use of immunosuppressant drugs. Squamous cell carcinoma of skin can occur in these patients even after decades of organ transplant. A 45-year-old male underwent renal transplant for end-stage renal disease 23 years ago and was on immunosuppressive drugs since then. The patient was on regular follow-up. Three years back, he developed squamous cell carcinoma of both forearms and hands, which was treated with radiation therapy using 8 MeV electrons, by parallel opposed fields to a dose of 60 Gy/30 fractions. Complete response to treatment was achieved at 3 months posttreatment. The patient is currently on follow-up and asymptomatic for skin lesions. Hence, these patients require longer follow-up, active surveillance, and screening for early diagnosis and prompt treatment of the premalignant and malignant conditions.

Effector Antitumor and Regulatory T Cell Responses Influence the Development of Nonmelanoma Skin Cancer in Kidney Transplant Patients

BACKGROUND

Chronic immunosuppression promotes nonmelanocytic squamous cell carcinoma (SCC) after kidney transplantation. Adaptive and innate immunity play a key role controlling tumor growth and are influenced by different immunosuppressive agents. We hypothesized that functional impairment of tumor-specific T cell responses due to calcineurin inhibitors (CNI) could contribute to SCC development, whereas conversion to mammalian target of rapamycin inhibitors (mTOR-i) could recover this protective immune response.

METHODS

Peripheral tumor-specific T cell responses against main SCC-derived antigens using the IFN-γ enzyme-linked immunospot assay and intratumor (IT) and circulating immune phenotypes (CD4 + T, CD8 + T, CD20 + B, CD56 + NK, FOXP3 + regulatory T [Treg] cells) were explored in a cross-sectional analysis in 59 kidney transplant patients with SCC on CNI (KT-CNI-SCC) or mTOR-i (KT-mTORi-SCC), 25 nontransplants developing SCC (NoKT-SCC) and 6 healthy controls. Moreover, 25 KT-CNI-SCC were switched to mTOR-i and evaluated after 12 months.

RESULTS

Kidney transplant patients showed lower IT infiltrates and tumor-specific T cell responses than NoKT-SCC, and intratumoral and circulating FOXP3 + Treg cells were higher in KT-mTORi-SCC (P < 0.05). Tumor-specific T cell responses were significantly lower in KT-CNI-SCC than KT-mTORi-SCC and NoKT-SCC and predicted SCC relapses (area under the curve = 0.837; P < 0.05). One-year after mTOR-i conversion, a significant increase in FOXP3 + Treg cell numbers and tumor-specific T cell responses were observed, reaching similar levels than KT-mTORi-SCC and NoKT-SCC patients.

CONCLUSIONS

Tumor-specific T cell responses are strongly impaired in CNI-treated patients but recover after mTOR-i conversion, reducing SCC relapses.

Risk Factors of Graft Survival After Diagnosis of Post-kidney Transplant Malignancy: Using Cox Proportional Hazard Model

BACKGROUND

All recipients of kidney transplantation, especially those with posttransplant malignancy, are at risk of long-term graft failure.

OBJECTIVES

The purpose of our study was to evaluate the risk factors associated with graft survival after diagnosis of malignancy.

PATIENTS AND METHODS

To reach this purpose, we conducted a historical cohort study in Iran and 266 cases with posttransplant malignancy were followed up from diagnosis of malignancy until long-term graft loss or the date of last visit. These patients were taken as a census from 16 Transplant Centers in Iran during 22 years follow-up period since October 1984 to December 2008. A Cox proportional hazards model was performed to determine the important independent predictors of graft survival after malignancy.

RESULTS

At the end of the study, long-term graft failure was seen in 27 (10.2%) cases. One-year and 2-year graft survival after diagnosis of cancer were 93.6% and 91.7%, respectively. The univariate analysis showed that the incidence of chronic graft loss was significantly higher in male patients with solid cancers, withdrawal of immunosuppressant regimen, no response to treatment, and tumor metastasis. In continuation, the Cox model indicated that the significant risk factors associated with graft survival were type of cancer (P < 0.0001), response to treatment (P < 0.0001, HR = 0.14, 95% CI: 0.06 - 0.32), metastasis (P < 0.0001, HR = 5.68, 95% CI: 2.24 - 14.42), and treatment modality (P = 0.0001).

CONCLUSIONS

By controlling the modifiable risk factors and modality of treatment in our study, physicians can reach more effective treatment.

Gastric cancer and the epoch of immunotherapy approaches

The incidence of gastric cancer (GC) fell dramatically over the last 50 years, but according to IARC-Globocan 2008, it is the third most frequent cause of cancer-related deaths with a case fatality GC ratio higher than other common malignancies. Surgical resection is the primary curative treatment for GC though the overall 5-year survival rate remains poor (approximately 20%-25%). To improve the outcome of resectable gastric cancer, different treatment strategies have been evaluated such as adjuvant or perioperative chemotherapy. In resected gastric cancer, the addition of radiotherapy to chemotherapy does not appear to provide any additional benefit. Moreover, in metastatic patients, chemotherapy is the mainstay of palliative therapy with a median overall survival of 8-10 mo and objective response rates of merely 20%-40%. Therefore, the potential for making key beneficial progress is to investigate the GC molecular biology to realize innovative therapeutic strategies, such as specific immunotherapy. In this review, we provide a panoramic view of the different immune-based strategies used for gastric cancer treatment and the results obtained in the most significant clinical trials. In detail, firstly we describe the therapeutic approaches that utilize the monoclonal antibodies while in the second part we analyze the cell-based immunotherapies.

X-shaped DNA potentiates therapeutic efficacy in colitis-associated colon cancer through dual activation of TLR9 and inflammasomes

Background

Immunotherapy has been extensively pursed as a promising strategy for the treatment of cancer. Pattern-recognition receptors (PRRs) play important roles in triggering activation of innate and adaptive immunity. Therefore, agents that stimulate PRRs could be useful for cancer immunotherapy. We developed two kinds of X-shaped double-stranded oligodeoxynucleotides (X-DNA), a single unit of X-DNA (X_S-DNA) composed of four strands of DNA and a ligated X-DNA complex (X_L-DNA) formed by crosslinking each X_S-DNA to the other, and investigated if they had immunostimulatory activity and could be applied to anti-cancer immunotherapy.

Methods

Activation of MAPKs and NF-κB was determined by immunoblotting in bone marrow-derived primary dendritic cells (BMDCs). Immune cytokines and co-stimulatory molecules were measured by ELISA and flow cytometry analysis. Anti-cancer efficacy was examined in an azoxymethane/dextran sulfate sodium-induced colitis-associated colon cancer mouse model. Association of X-DNA and TLR9 was determined by co-immunoprecipitation followed by immunoblotting. The involvement of TLR9 and inflammasomes was determined using TLR9- or caspase-1-deficient BMDCs. Inflammasome activation was examined by degradation of pro-caspase-1 to caspase-1 and cleavage of pro-IL-1β to IL-1β in BMDCs.

Results

X_L-DNA and X_S-DNA induced activation of MAPKs and NF-κB and production of immune cytokines and co-stimulatory molecules in BMDCs. BMDCs stimulated by X_L-DNA induced differentiation of naïve CD4⁺ T cells to T_H1 cells. Intravenous injection of X_L-DNA into mice resulted in increased serum IFN-γ and IL-12 levels, showing in vivo efficacy of X_L-DNA to activate T_H1 cells and dendritic cells. X_L-DNA greatly enhanced the therapeutic efficacy of doxorubicin, an anti-cancer drug, in colitis-associated colon cancer. X_L-DNA directly associated with TLR9. In addition, immunostimulatory activities of X-DNA were abolished in TLR9-deficient dendritic cells. Furthermore, X-DNA induced caspase-1 degradation and IL-1β secretion in BMDCs, which were abolished in caspase-1-deficient cells.

Conclusions

X-DNA induced the activation of dendritic cells as shown by the expression of immune-cytokines and co-stimulatory molecules, resulting in the differentiation of T_H1 cells, mediated through dual activation of TLR9 and inflammasomes. X-DNA represents a promising immune adjuvant that can enhance the therapeutic efficacy of anti-cancer drugs by activating PRRs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0369-2) contains supplementary material, which is available to authorized users.

Metastatic Neuroendocrine Tumour in a Renal Transplant Recipient: Dual-Tracer PET-CT with (18)F-FDG and (68)Ga-DOTANOC in This Rare Setting

Recipients of renal transplant are at increased risk of developing various malignancies, especially post-transplant lymphoproliferative disorder (PTLD) and skin cancers. Neuroendocrine tumours (NET) of the gastrointestinal tract have not been reported in this setting. Here we describe the case of a 75-year-old male who had undergone renal transplant 8 years back and now presented with significant weight loss and backache, clinically suspected as PTLD. (18)F-Fluordeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) showed hypermetabolic lesions in the liver and rectum, raising the suspicion of PTLD. However, biopsy from the liver lesion showed poorly differentiated NET. (68)Ga-labelled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-NaI(3)-octreotide ((68)Ga-DOTANOC) PET-CT was then done, which confirmed the primary lesion in the rectum with liver metastases.

Outcomes of kidney transplant tourism and risk factors for de novo urothelial carcinoma

BACKGROUND

To date, the outcomes of transplant tourism have not been reported extensively. In addition, data about the accuracy of urine cytology for the detection and the role of the BK virus (BKV) in the carcinogenesis of urothelial carcinoma (UC) after renal transplantation are lacking.

METHODS

Three hundred seven patients who received deceased donor kidney transplants between January 2003 and December 2009 were retrospectively studied. The clinical parameters and outcomes between the domestic and tourist groups were compared. We also investigated the risk factors and role of BKV in the carcinogenesis of de novo UC by quantitative real-time polymerase chain reaction.

RESULTS

The subjects in the tourist group were older at transplantation and had a shorter dialysis time before transplantation. There were significantly higher incidence rates of BKV viruria, Pneumocystis jiroveci pneumonia, and malignancy in the tourist group. Graft and patient survival were superior in the domestic group. A total of 43 cancers were identified, and the most common type of malignancy was UC (23 patients, 53.5%). The tourist group had a significantly higher incidence of tumors. The sensitivity and specificity of urine cytology for detecting UC were 73.9% and 94.7%, respectively. Independent predictors of UC included female sex, use of Chinese herbal medicine, and transplant tourism. Only two patients (8.7%) with UC had detectable BKV.

CONCLUSIONS

Transplant tourism was a risk factor for infection and de novo malignancy. Urothelial carcinoma was the most common malignancy after kidney transplantation. Regular screening for the early detection of UC by urine cytology or periodic sonographic surveys is mandatory, especially for those at high risk.

Epidemiology of post-transplant malignancy in Asian renal transplant recipients: a population-based study

OBJECTIVE

Using Taiwan's National Health Insurance Research Database, this large population-based study was conducted to explore the incidences and risk factors of post-transplant malignancy in Asian renal transplant recipients.

PATIENTS AND METHODS

A total of 642 patients who firstly underwent renal transplant between January 1, 2000 and December 31, 2008 were identified from a 2 million cohort. The primary endpoint was a subsequent hospitalization with a primary diagnosis of malignancy (ICD-9-CM code: 140.xx-239.xx) after renal transplantation. All patients were followed until the occurrence of endpoints or the end of the study (December 31, 2010), whichever came first. Adjusted risks of post-transplant cancer were analyzed using Cox proportional hazards regression model. All models were adjusted for baseline characteristics, comorbid diseases, transplant year, and exposure to immunosuppressive agents.

RESULTS

Among 642 renal transplant patients, 54 cancers (8.4 %) were identified. The median time between transplant and cancer diagnosis was 46.2 (range 8.5-107.4) months. Cancers of kidney and other unspecified urinary organs was the most common cancer sites, accounted for 18.5 % of the malignancies diagnosed. The next most common cancer sites were trachea, bronchus, and lung (14.8 %), bladder (13.0 %), liver and intrahepatic bile ducts (11.1 %), colon (5.6 %), and prostate (5.6 %). Age at transplantation was a statistically significant risk factor of post-transplant cancer in our study. Increased risks of post-transplant cancer were observed in patients who received immunosuppression agents (cyclosporine (HR 1.26, 95 % CI 0.58-2.77, p = 0.5603), tacrolimus (HR 1.99, 95 % CI 0.66-6.00, p = 0.2197), and mycophenolate (HR 1.00, 95 % CI 0.40-2.45, p = 0.9874)) although the estimates were not statistically significant.

CONCLUSIONS

Our population-based cohort study offers additional insight into post-transplant cancers in Asian population. Further studies are warranted to assess the association between specific immunosuppression agents and post-transplant cancers.

Multiple unrelated malignancies following renal transplantation: an evaluation of four cases

The risk of de novo malignancy is significantly higher in patients who have undergone organ transplantation than in the general population. Long-term immunosuppressive treatment, in addition to age, genetic predisposition and infectious agents, plays a major role in the development of malignancy. Although skin and hemopoietic system cancers are common, atypical presentations of malignancies may occasionally be seen during long-term follow-up in patients with functioning allografts. In this report, four cases, each with more than one different primary malignancy (one patient with three malignancies and three patients with two malignancies), are presented.

Rituximab in idiopathic membranous nephropathy

Selective depletion of B cells with the mAb rituximab may benefit the autoimmune glomerular disease idiopathic membranous nephropathy (IMN). Here, we describe our experience treating 100 consecutive IMN patients with persistent nephrotic syndrome with rituximab. We defined complete remission as persistent proteinuria <0.3 g/24 h and partial remission as persistent proteinuria <3 g/24 h, each also having >50% reduction in proteinuria from baseline. During a median follow-up of 29 months after rituximab administration, 65 patients achieved complete or partial remission. The median time to remission was 7.1 months. All 24 patients who had at least 4 years of follow-up achieved complete or partial remission. Rates of remission were similar between patients with or without previous immunosuppressive treatment. Four patients died and four progressed to ESRD. Measured GFR increased by a mean 13.2 (SD 19.6) ml/min per 1.73 m(2) among those who achieved complete remission. Serum albumin significantly increased and albumin fractional clearance decreased among those achieving complete or partial remission. Proteinuria at baseline and the follow-up duration each independently predicted the decline of proteinuria. Furthermore, the magnitude of proteinuria reduction significantly correlated with slower GFR decline (P=0.0001). No treatment-related serious adverse events occurred. In summary, rituximab achieved disease remission and stabilized or improved renal function in a large cohort of high-risk patients with IMN.

HPV-related (pre)malignancies of the female anogenital tract in renal transplant recipients

Renal transplantations (RTs) are performed routinely in many countries. After RT, the administration of lifelong immunosuppressive therapy is required. As a consequence, renal transplant recipients (RTRs) have a high risk to develop virus-associated (pre)malignancies, such as Human papillomavirus (HPV) related anogenital (pre)malignancies. It is known that the majority of the RTRs are infected with HPV and that these women have a 14-fold increased risk of cervical cancer, up to 50-fold of vulvar cancer and up to 100-fold of anal cancer. Often, treatment of these lesions requires concessions and may be suboptimal as radiation therapy and extensive surgery may damage the renal transplant. Therefore, prognosis may be compromised due to inadequately treated malignancies. Especially for these immunocompromised patients prevention is of utmost importance. Yearly cervical cancer screening for RTRs is advised, but appears to be executed poorly. For the future, optimizing screening and prevention of anogenital (pre)malignancies is an important issue for women after RT. This review gives a broad overview of all aspects regarding HPV-related (pre)malignancies of the female anogenital tract in RTRs.

Novel immunotherapeutic strategies of gastric cancer treatment

Gastric cancer (GC) is the fourth most common cancer and the second most frequent cause of cancer-related deaths, accounting for 10.4% of cancer deaths worldwide. Despite the improvements, estimated cure rates for patients with advanced stages remain poor, and in the metastatic setting, chemotherapy is the mainstay of palliative therapy and results in objective response rates (ORRs) of only 20-40% and median overall survivals (OS) of 8-10 months. Therefore, many investigators believe that the potential for making significant progress lies in understanding and exploiting the molecular biology of these tumors to investigate new therapeutic strategies to combat GC, such as specific immunotherapy. In this paper, we analyze the different approaches used for immune-based (especially dendritic and T cells) therapies to gastric cancer treatment and discuss the results obtained in preclinical models as in clinical trials.

Biomarkers as a tool for management of immunosuppression in transplant patients

Therapeutic drug monitoring is a well-established approach in transplantation medicine to guide immunosuppressive therapy. However, it cannot always predict the effects of immunosuppressive drugs on immune cells, because it does not reflect any aspect of an individual patient's immune system. Pharmacodynamic monitoring is a more recent strategy to provide information about the biologic effect of a specific drug or drug combination on the individual transplant patient. Currently, there is a large number of different biomarkers that either directly (specific markers) or indirectly (global markers) relate to the pharmacodynamic effects of immunosuppressive drugs and are under investigation as potential candidates to be introduced in clinical practice. Such biomarkers may be useful to identify patients at risk of developing acute rejection, infection, or cancer as well as patients who are suitable for minimization of immunosuppressant therapy and may be helpful to manage the timing and rate of immunosuppressant weaning. Serial longitudinal monitoring may allow maintenance of an individualized immunosuppressive regimen. Thus, biomarker monitoring is a potential complementary tool to therapeutic drug monitoring. This review summarizes the current state of knowledge about the use of a number of global or drug-specific pharmacodynamic biomarkers. It is not a comprehensive overview of the literature available, but rather an evidence-based reflection by experts who are intensively involved in scientific work in this field.

[Management of renal toxicity in HIV-positive patients. What to measure, how to measure it and how frequently]

Chronic kidney disease in patients with HIV is being recognized as one of the most frequent comorbidities of this disease and consequently much research is currently being performed in this area. The possible manifestations are highly varied and consequently a high index of suspicion is required. Appropriate investigations should be performed from the moment patients first seek care to rule out renal disease and to prevent worsening, with the diagnostic or therapeutic measures that may subsequently be required. One of the most common problems is nephrotoxicity caused by some drugs and cases associated with tenofovir are becoming more frequently described. However, there is wide clinical experience with this drug and renal toxicity associated with its use is uncommon both in clinical trials and in clinical practice. Familiarity with what may happen, the associated factors and appropriate patient management are essential.

Outcome of patients on renal replacement therapy after colorectal surgery

PURPOSE

Patients on renal replacement therapy are reported to have a high complication rate after abdominal surgery, the result of uremia and immunosuppression. A review of this group of patients undergoing colorectal surgery was undertaken.

METHODS

Seventy-three separate colorectal operations were performed for 44 patients. Thirty-eight patients were on dialysis and 35 had a renal transplant. Data (coexisting disease, preoperative blood results, operative details, complications, and colorectal POSSUM score) were completed for each surgical event.

RESULTS

Forty-two elective and 31 emergency procedures were performed. Infective complications were common (overall 60 percent). There were two anastomotic leaks in the elective group, but five leaks from seven emergency anastomoses. Stomas were frequently raised. Ninety percent of patients who survived and had a defunctioning stoma underwent a successful reversal. The overall major complication rate after elective and emergency surgery was 19 and 81 percent, respectively, and mortality was 5 and 26 percent, respectively.

CONCLUSIONS

Renal patients have a high rate of complications after colorectal surgery, and emergency surgery has a significant risk of anastomotic leak. Primary anastomosis should be avoided in all patients undergoing emergency intestinal resections. Subsequent surgery to restore intestinal continuity is possible in 90 percent of patients with far fewer complications.

Immunosuppressive therapy and malignancy in organ transplant recipients: a systematic review

Post-transplant malignancy is recognised as being a major limitation to the success of solid organ transplantation and it is currently considered one of the unavoidable costs of long-term immunosuppressive therapy. However, the continual introduction of new immunosuppressive drugs and the growing knowledge about their different oncogenic profiles, requires a continuous evaluation of the available evidence on this topic. The incidence and risk of malignancy is elevated in solid organ transplant recipients compared with the general population. As proof of the relationship between immunosuppressive therapy and post-transplant malignancy, epidemiological data reveal that the length of exposure to immunosuppressive therapy and the intensity of therapy are clearly related to the post-transplant risk of malignancy, and that once cancer has developed, more intense immunosuppression can translate into more aggressive tumour progression in terms of accelerated growth and metastasis and lower patient survival. The association between malignancy and immunosuppressive therapy is mediated through several pathogenic factors. Indirectly, immunosuppressive drugs greatly increase the post-transplant risk of malignancy by impairing cancer surveillance and facilitating the action of oncogenic viruses. However, the direct pro- and anti-oncogenic actions of immunosuppressants also play an important role. The cancer-promoting effect of calcineurin inhibitors, independently of depressed immunosurveillance, has been demonstrated in recent years, and currently only mammalian target of rapamycin (mTOR) inhibitors have shown simultaneous immunosuppressive and antitumour properties. Reports of the initial results of the reduced incidence of cancer in organ transplant recipients receiving mTOR inhibitor therapy strongly indicate separate pathways for pharmacological immunosuppression and oncogenesis. The role of mTOR inhibitors has been firmly established for the treatment of post-transplant Kaposi's sarcoma and its role in the management of patients with other post-transplant malignancies should be clarified as soon as possible. Prevention of morbidity and mortality resulting from post-transplant malignancy should become a main endpoint in solid organ transplant programmes, and the choice and management of immunosuppressive therapy in each phase of transplantation plays a central role in this objective. Although comprehensive and rigorous information about the management of immunosuppressive therapy in transplant recipients at risk of or affected by cancer is still lacking, new experimental and clinical data about mTOR inhibitors offers novel approaches to this problem.

Laryngotracheal reconstruction using prefabricated and preconditioned composite radial forearm free flaps

OBJECTIVE

Total or subtotal laryngectomy performed as surgical treatment of locally advanced laryngeal tumors requires a permanent laryngostomy or tracheostomy, and are both associated with severe and lifelong disability. The hitherto published reconstructive methods for the rehabilitation of patients after subtotal anterior laryngotracheal resection of extended laryngotracheal malignancies have not been thoroughly convincing.

METHODS

We present a successful method of extended laryngotracheal reconstruction that combines modern surgical and biomedical techniques.

RESULTS

A stable three-dimensional anterior neolarynx was prefabricated, including the use of vacuum-assisted prelamination and preconditioning of a composite radial forearm free flap, which was then transferred to the neck and vascularized by microvascular anastomosis to the cervical vessels. This reconstructive procedure permitted the restoration of a stable laryngotracheal conduit in two cases, with the subsequent successful closure of the tracheo-laryngostomy.

CONCLUSION

In the reported cases the pre- or post-operative irradiation did not compromise the success of reconstruction. Not only did our technique facilitate the rehabilitation of patients suffering from drawbacks of the laryngo-tracheofissure, but it also assisted in avoiding total laryngectomy in cases of advanced anterior laryngeal cancer by extending the indications for subtotal anterior laryngeal resections followed by reconstructive surgery.

Cancer immunoediting from immune surveillance to immune escape

Cancer immune surveillance is considered to be an important host protection process to inhibit carcinogenesis and to maintain cellular homeostasis. In the interaction of host and tumour cells, three essential phases have been proposed: elimination, equilibrium and escape, which are designated the 'three E's'. Several immune effector cells and secreted cytokines play a critical role in pursuing each process. Nascent transformed cells can initially be eliminated by an innate immune response such as by natural killer cells. During tumour progression, even though an adaptive immune response can be provoked by antigen-specific T cells, immune selection produces tumour cell variants that lose major histocompatibility complex class I and II antigens and decreases amounts of tumour antigens in the equilibrium phase. Furthermore, tumour-derived soluble factors facilitate the escape from immune attack, allowing progression and metastasis. In this review, the central roles of effector cells and cytokines in tumour immunity, and the escape mechanisms of tumour cells during tumour progression are discussed.

Cancer immunoediting from immune surveillance to immune escape

Cancer immune surveillance is considered to be an important host protection process to inhibit carcinogenesis and to maintain cellular homeostasis. In the interaction of host and tumour cells, three essential phases have been proposed: elimination, equilibrium and escape, which are designated the 'three E's'. Several immune effector cells and secreted cytokines play a critical role in pursuing each process. Nascent transformed cells can initially be eliminated by an innate immune response such as by natural killer cells. During tumour progression, even though an adaptive immune response can be provoked by antigen-specific T cells, immune selection produces tumour cell variants that lose major histocompatibility complex class I and II antigens and decreases amounts of tumour antigens in the equilibrium phase. Furthermore, tumour-derived soluble factors facilitate the escape from immune attack, allowing progression and metastasis. In this review, the central roles of effector cells and cytokines in tumour immunity, and the escape mechanisms of tumour cells during tumour progression are discussed.

Managing Breast Cancer in the Renal Transplant Patient: A Unique Dilemma

Improvements in immunosuppression have increased patient and graft survival in transplant recipients. As a result, there is greater risk of neoplastic processes such as breast cancer. Treatment in this population is complicated by the necessary immunosuppression, vascular accesses, and transplant grafts. General surgeons may expect to encounter more of these complex patients in the community setting. We sought to evaluate the surgical treatment of breast cancer in patients with renal transplants. Hospital and private physician records were queried to identify patients who developed breast cancer after a renal or pancreatic/renal transplantation. These charts were reviewed for demographics, type of breast cancer and treatment, location of dialysis access, and complications. From June 1, 1994, to May 31, 2004, 14 patients were identified. Eight patients had functioning transplants. All patients underwent operative interventions. Ten patients underwent adjuvant treatment. Three had functioning transplants and chose not to risk the graft with cessation of immunotherapy. However, no patient with functioning transplants who underwent chemotherapy developed organ failure. Breast cancer after transplantation poses a unique dilemma. The threat of transplanted organ failure is a major concern to these patients and often supersedes adjuvant therapies.

Cancer immunotherapy

Cancer is the second leading cause of death in the industrialized world. Most cancer patients are treated by a combination of surgery, radiation and/or chemotherapy. Whereas the primary tumor can, in most cases, be efficiently treated by a combination of these standard therapies, preventing the metastatic spread of the disease through disseminated tumor cells is often not effective. The eradication of disseminated tumor cells present in the blood circulation and micro-metastases in distant organs therefore represents another promising approach in cancer immunotherapy. Main strategies of cancer immunotherapy aim at exploiting the therapeutic potential of tumor-specific antibodies and cellular immune effector mechanisms. Whereas passive antibody therapy relies on the repeated application of large quantities of tumor antigen-specific antibodies, active immunotherapy aims at the generation of a tumor-specific immune response combining both humoral and cytotoxic T cell effector mechanisms by the host's immune system following vaccination. In the first part of this review, concurrent developments in active and passive cancer immunotherapy are discussed. In the second part, the various approaches for the production of optimized monoclonal antibodies used for anti-cancer vaccination are summarized.

Hepatocellular carcinoma in renal transplant patients

INTRODUCTION

Chronic liver diseases, especially those related to hepatitis B (HBV) and C viruses (HCV), are a common problem in renal transplant patients. Hepatocellular carcinoma (HCC) is a complication of chronic liver diseases, incidence in the renal transplant cohort is higher than in the general population (1.4% to 4% vs 0.005% to 0.015%).

METHODS

We retrospectively evaluated the incidence of HCC, its clinical presentation, the treatments, and the relation to chronic viral hepatitis among the population transplanted at our center between January 1980 and December 1998 and followed to August 2003.

RESULTS

During the study period, six recipients among 534 renal transplants displayed HCC (incidence 1.12% of the entire population and 2.29% of patients with chronic viral hepatitis). Among the cohort five were men, and all had chronic viral hepatitis: three HBV, one HCV, and 2, a coinfection. HCC was diagnosed 124.1 (range 45 to 244) months after transplantation. All patients presented with abnormal liver function tests and tumors larger than 5 cm. Four had more than three tumors and three had an alpha-fetoprotein level higher than 400 IU/mL. Three patients received no treatment (survivals 1, 1, and 4 months); two patients, chemoembolization (survival 6 and 12 months); and one, surgical ethanol injections (survival 4 months). The overall survival was 4.5 months.

CONCLUSION

HCC in renal transplant recipients is a common complication among patients with chronic viral hepatitis. The outcome was poor because HCC was detected at an advanced stage. Screening strategies for early diagnosis must be prospectively evaluated.

Transmission of Malignancy with Solid Organ Transplants

Donor-derived malignancy is found in about 0.02-0.2% of allograft recipients. With an increasing number of older donors, this problem will gain more relevance in the future. We wish to review the current literature on tumor transmission with solid organ transplants and focus on the consequences of an extension of the donor pool, such as by the use of donors with a history of cancer. Finally, suggestions are made for screening regimens for living as well as cadaveric donors to minimize the risk of inadvertent tumor transmission.

Sick Leave due to Depressive Disease: Not a Risk Factor for the Development of Malignant Lymphoma

For unknown reasons the incidence of non-Hodgkin's Lymphomas (NHL) has increased during the last decades. Conditions with impaired immune functions have been associated with an increased risk of malignant lymphomas. Interactions between the central nervous, immune, and endocrine systems have been recently identified, and the potential physiological importance of these interactions is being explored. In this prospective cohort study the potential association between an increasing incidence of depressive disorders and the development of malignant lymphoma is being explored. The participants were part of the Swedish manpower on sick leave between 1988 and 2000 with depressive disease for more than two weeks were followed until a diagnosis of lymphoid malignancy, death, emigration, or end of follow-up period. The final cohort included 87,677 individuals with 373,135 years of follow-up. There were 80 cases of NHL, chronic lymphocytic leukemia (CLL), and Hodgkin lymphoma (HL) with 70 cases expected. The first year of follow-up showed a slightly increased risk of NHL, which most probably can be interpreted as initial symptoms of lymphoma. We conclude that the increase in the incidence of malignant lymphomas observed during the last decades seems not to be associated with a concurrent increase of depressive disorders.

Non-Hodgkin's lymphoma and other nonhepatic malignancies in Swedish patients with hepatitis C virus infection

The aim of this study was to evaluate the association between hepatitis C virus (HCV) infection and non-Hodgkin's lymphoma (NHL), multiple myeloma (MM), thyroid cancer (TC), chronic lymphatic leukemia (CLL), acute lymphatic leukemia (ALL), and Hodgkin's lymphoma (HL). A Swedish cohort of 27,150 HCV-infected persons notified during 1990-2000 was included in the study. The database was linked to other national registers to calculate the observation time, expressed as person-years, and to identify all incident malignancies in the cohort. The patients were stratified according to assumed time of previous HCV infection. The relative risk of malignancy was expressed as a standardized incidence ratio (SIR)-the observed number compared to the expected number. During 1990-2000 there were 50 NHL, 15 MM, 14 ALL, 8 TC, 6 CLL, and 4 HL diagnoses in the cohort. Altogether, 20 NHL, 7 MM, 5 TC, 4 CLL, 1 ALL, and 1 HL patient fulfilled the criteria to be included in the statistical analysis. The observation time was 122,272 person-years. The risk of NHL and MM was significantly increased in the stratum with more than 15 years of infection (SIR 1.89 [95% CI, 1.10-3.03] and 2.54 [95% CI, 1.11-5.69], respectively). The association was not significant in TC or CLL. In conclusion, we report the incidence of several malignancies in a nationwide cohort of HCV-infected persons. Although the delayed diagnosis of HCV probably has resulted in an underestimation of the risk, this study showed a significantly increased risk of NHL and MM.

Risk of malignancy with long-term immunosuppression in renal transplant recipients

BACKGROUND

Improvements in immunosuppressive regimens have significantly enhanced patient and graft survival in renal transplant recipients. However, susceptibility to neoplastic disorders is increased as a consequence of prolonged immunosuppression. Available data pertaining to cancer risks in renal transplant recipients have been inconsistent, and much of it is derived from international studies, which may not be truly representative of the United States population.

METHODS

We studied a total of 1979 transplants performed in 1739 patients from a single center in the United States with a mean follow-up of 6.1 years, and a total of 9852 person-years' follow-up.

RESULTS

The mean age at the time of diagnosis of cancer was 50 years, and the mean interval between transplant and diagnosis of cancer was 95 months. Older patients receiving a transplant had a significantly higher risk for developing cancer as opposed to younger patients (RR 6.2 for >60 years compared with <40 years). When compared with the general population using data from the Surveillance, Epidemiology and End Results (SEER) registry, the overall risk for nonskin malignancies was modestly increased in our transplant recipients, with a standardized incidence ratio (SIR) of 1.4 (P= 0.01). When stratified by age groups, younger age at transplant (<40 years) had the highest SIR, at 2.3 (P < 0.001). Similarly, duration post-transplant >10 years had an SIR of 2.4 (P < 0.001).

CONCLUSION

We believe that this study is representative of the United States' renal transplant population, and highlights the need for reduced immunosuppression in the long-term and increased vigilance for cancers in younger patients receiving renal transplantation.

Racial and ethnic variations in incidence and pattern of malignancies after kidney transplantation

Malignancies are a well-recognized complication of renal transplantation. Although the problem is well studied in developed countries, less is known about it in developing countries. Although geographic and ethnic variations have been alluded to in several reports, to our knowledge the subject has not been investigated formally. From April 1976 through March 1999, 41 (7.6%) patients were diagnosed with cancer among a heterogeneous population of renal allograft recipients treated at our institution in Cape Town, South Africa. The incidence of malignancies was comparable in white and nonwhite patients. However, squamous cell cancer and basal cell cancer of the skin (in that order) were the most common cancers in white patients, in whom they occurred exclusively. On the other hand, Kaposi sarcoma was the most common cancer in nonwhite renal allograft recipients, in whom it accounted for almost 80% of all cancers. Review of the world literature suggests that posttransplant cancers are less common in developing countries; Kaposi sarcoma is the most common lesion, with few exceptions. Malignant lymphomas are also more common in developing countries. The impact of different immunosuppressive regimens is controversial. In general, cyclosporine is not associated with a significant increase in the incidence of cancer after renal transplantation, although the time to the first cancer may be reduced. In our experience, the pattern of posttransplant cancers in white and nonwhite patients living in the same geographic region epitomizes the world experience of the disease and suggests that genetic factors, rather than geography, are the more important determinants of cancer development after renal transplantation.

Papillary renal cell carcinoma in allograft kidney

Papillary renal cell carcinoma is a subgroup of malignant renal epithelial neoplasms. Its occurrence in allograft transplanted kidney has not been debated in the literature. We report two pathologically proven cases and discuss the clinical hypothesis for such neoplasms and the aspect on MR images. The paramagnetic effect of the iron associated with an absence of signal coming from calcifications is a plausible explanation for this unusual hypo-intense appearance on T2-weighted sequence.

Outcomes in kidney transplantation

It is estimated that there are greater than 100000 kidney transplant recipients with a functioning graft in the United States. Recent advances in immunosuppression have improved short-term graft survival rates and decreased early mortality by decreasing the incidence and therapy for acute rejection episodes. For those accepted on the waiting list, transplant prolongs patient survival compared with remaining on dialysis. During the 1990s, 3 new immunosuppressive drugs were introduced in clinical kidney transplantation. All were approved for use by the Food and Drug Administration after large, controlled, randomized trials. Mycophenolate mofetil (MMF), when combined with cyclosporine (CSA) and prednisone, lowered acute rejection rates by nearly 50% compared with control. Tacrolimus compared with CSA also significantly reduced acute rejection rates in kidney transplant recipients, but was associated with a significant increase in posttransplant diabetes mellitus (PTDM) in the early trials. When evaluated in combination with MMF, the incidence of PTDM was much lower. At the end of the decade, sirolimus was shown in several randomized trials to lower acute rejection rates and is believed to be less nephrotoxic compared with calcineurin inhibitors. All of the randomized trials were not statistically powered to assess long-term superiority. Registry analyses have been performed that appear to show some long-term benefit of immunosuppressive therapy with MMF. Other outcome assessments in kidney transplant recipients include risk factors for chronic allograft nephropathy, hypertension, hyperlipidemia, and bone disease. Although there are few randomized trials, understanding of the significance of these common complications has progressed and strategies for therapy and intervention have been developed. This article focuses on the randomized trials of immunosuppressive therapy and complications associated with use of these drugs. In addition, we review the current management and intervention for the comorbidities associated with the long-term clinical management of the kidney transplant recipient.

Tumours after kidney transplantation

PURPOSE OF REVIEW

With the improved long-term outcome of renal allograft recipients, malignant tumours or cardiovascular disease become increasingly important. Malignant tumours develop in 15-20% of graft recipients after 10 years, and thus contribute substantially to the morbidity and mortality of these patients. In contrast to the general population, skin tumours and lymphoproliferative disorders are the most frequent malignancies in transplant recipients. Malignancies can develop in three ways: de-novo occurrence in the recipient; recurrent malignancy in the recipient; or transmission of malignancy from the donor.

RECENT FINDINGS

The immunosuppressive strategies after renal transplantation differ with respect to the development of malignancies, with cell-depleting antibodies being the highest risk, whereas newer immunosuppressants such as rapamycin could possess anti-tumour potential. The relationship of chronic viral infections to skin tumours and lymphoproliferative diseases has become clearer during recent years. Concomitantly, experience in the management of such diseases has grown. Furthermore, as older donors are accepted, awareness of the possibility of transferring malignancies from the donor to the recipient must increase.

SUMMARY

Malignancies are a major contributor to morbidity and mortality among kidney transplant recipients as such diseases gain importance with longer graft survival. Immunosuppression and chronic viral infections in combination with the transmission of malignant cells from the donor or recurrent malignancies contribute to the increased incidence of cancer. In kidney transplant recipients, screening before and after transplantation and an individualized choice of immunosuppression are thus mandatory.

An uncommon tumor in a renal graft recipient: a diagnostic and therapeutic challenge

The development of malignancies after solid organ transplantation represents an increasing clinical problem complicating the long-term follow-up of transplant recipients. In this case report the authors describe the rare triple combination of a simultaneous hepatocellular carcinoma with a glucagonoma and a splenic hamartoma in a renal allograft recipient. It is not only the first published report of a glucagonoma occurring after renal transplantation but serves also as an illustration of the therapeutic decision making in the setting of the immune-compromised host. This case report also illustrates the different imaging modalities that can be used for the diagnosis of neuroendocrine tumors.