Conversion to sirolimus in renal transplant patients with tumors

Sirolimus in renal transplant recipients with malignancies in Germany

Background

Renal transplant recipients have an increased cancer risk. The mammalian target of rapamycin inhibitor sirolimus (SRL) has immunosuppressive and antitumour activities but knowledge about its use in recipients with cancer is limited.

Methods

We retrospectively analysed 726 renal allograft recipients converted to SRL from 10 German transplant centres. Patient and graft survival were analysed depending on malignancy status prior to conversion and tumour entity.

Results

Malignancy before conversion to SRL was reported in 230 patients, with 137 patients having skin cancers and 101 having solid cancers. Cancer occurred 4.6 ± 9.4 (median 3.0) years after transplantation. Basal cell carcinoma, squamous cell carcinoma and Bowen’s disease were the most prevalent skin cancers, while carcinomas of the kidney, colon and breast were the most prevalent solid cancers before conversion. Patients with prior malignancy were older and had better renal function at conversion compared with patients without a history of cancer. After conversion to SRL, cancer incidence rates (IRs) of all tumours were lower compared with rates before conversion. Cancer IRs after conversion were higher in patients with malignancy before conversion compared with those without. Patient survival was worse in patients with solid cancers compared with patients with skin cancers or without malignancies. Biopsy-proven acute rejections in the first year after conversion were less frequent in patients with malignancy compared with those without. Graft survival and renal function in all cancer types were better than in patients converted to SRL without cancers.

Conclusions

Conversion to SRL in patients with a history of cancer is safe regarding renal function and graft survival, while patient survival is largely dependent on tumour entity.

Peripheral natural killer cell and allo-stimulated T-cell function in kidney transplant recipients associate with cancer risk and immunosuppression-related complications

Reducing immunosuppression has been proposed as a means of preventing cancer in kidney transplant recipients but this can precipitate graft rejection. Here we tested whether anti-tumor natural killer (NK) cell and allo-responsive T-cell function in kidney transplant recipients may predict cancer risk and define risk of rejection. NK cell function was measured by the release of lactate dehydrogenase and T-cell allo-response by interferon-γ quantification using a panel of reactive T-cell enzyme-linked immunospot (ELISPOT) in 56 kidney transplant recipients with current or past cancer and 26 kidney transplant recipients without cancer. NK function was significantly impaired and the allo-response was significantly lower in kidney transplant recipients with cancer. With prospective follow-up, kidney transplant recipients with poor NK cell function had a hazard ratio of 2.1 (95% confidence interval 0.97-5.00) for the combined end point of metastatic cancer, cancer-related death, or septic death. Kidney transplant recipients with low interferon-γ release were also more likely to reach this combined end point. Thus, posttransplant monitoring of allo-immunity and NK cell function is useful for assessing the risk of over immunosuppression for the development of malignancy and/or death from cancer or sepsis.

Immune profiling and cancer post transplantation

Half of all long-term (> 10 year) australian kidney transplant recipients (KTR) will develop squamous cell carcinoma (SCC) or solid organ cancer (SOC), making cancer the leading cause of death with a functioning graft. At least 30% of KTR with a history of SCC or SOC will develop a subsequent SCC or SOC lesion. Pharmacological immunosuppression is a major contributor of the increased risk of cancer for KTR, with the cancer lesions themselves further adding to systemic immunosuppression and could explain, in part, these phenomena. Immune profiling includes; measuring immunosuppressive drug levels and pharmacokinetics, enumerating leucocytes and leucocyte subsets as well as testing leucocyte function in either an antigen specific or non-specific manner. Outputs can vary from assay to assay according to methods used. In this review we define the rationale behind post-transplant immune monitoring assays and focus on assays that associate and/or have the ability to predict cancer and rejection in the KTR. We find that immune monitoring can identify those KTR of developing multiple SCC lesions and provide evidence they may benefit from pharmacological immunosuppressive drug dose reductions. In these KTR risk of rejection needs to be assessed to determine if reduction of immunosuppression will not harm the graft.

[Remission of an iatrogenic Kaposi sarcoma in a patient with myasthenia gravis after switching immunosuppressive therapy to the mTOR inhibitor everolimus]

Iatrogenic Kaposi sarcomas (KS) in organ transplant recipients are often treated by switching immunosuppressive therapy to an mTOR inhibitor, such as sirolimus or everolimus, as these have immunosuppressive as well as anti-tumor effects. We report on an 80-year-old male patient who developed a disseminated cutaneous KS during therapy with prednisone and azathioprine for myasthenia gravis. After discontinuation of azathioprine therapy and despite continuing therapy with cortisone, the KS progressed and autoantibody levels against the nicotinic acetylcholine receptor increased. During the administration of everolimus, a long-term near-complete remission of KS and a decrease in autoantibodies took place. This case study illustrates that even in non-organ transplant patients with iatrogenic KS, switching to immunosuppressive therapy using an mTOR inhibitor can be beneficial.

The metabolic and toxicological considerations for mTOR inhibitors in the treatment of hepatocarcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is a major health problem worldwide. Several molecular pathways involved in HCC growth and progression have recently been identified. Rapamycin analogs are able to inhibit one of the most active oncogenic molecular pathways in HCC cells: the mammalian target of rapamycin (mTOR) pathway.

AREAS COVERED

In this review, the authors analyze the principal molecular features of the mTOR pathway and the use of rapamycin analogs in the treatment of hepatocarcinoma. The article also looks at the reoccurrence of HCC following liver transplantation as well as after the treatment of de novo neoplasms. Finally, the authors discuss the advantage of using a combined HCC pharmacological therapy to obtain a synergistic effect on tumor mass.

EXPERT OPINION

Among the available options for the treatment of advanced-stage HCC, mTOR pathway inhibitors show great promise. Once these agents have their safety and efficacy confirmed, in the treatment of liver disease, their use should be considered in patients affected by HCC. This should especially be the case for those who have had liver transplants or suffered with de novo tumors. Moreover, the authors believe that mTOR inhibitors could be used in a combined pharmacological approach to improve HCC molecular-targeted therapy by producing a multiple-level block of tumor intracellular signaling.

Evolution of glomerular filtration rate, renal injury markers, anemia, and angiotensin blockers use after change from calcineurin inhibitors to sirolimus in transplant patients with neoplasia versus chronic allograft nephropathy

BACKGROUND

The change from calcineurin inhibitors (CNI) to sirolimus (SRL) is a safe alternative in transplant patients with neoplasia (NEO) whereas the results of conversion for chronic allograft nephropathy (CAN) are controversial, depending on the histologic score, degree of proteinuria, and glomerular filtration rate (GFR). Our aim in this study was to compare GFR, proteinuria, albuminuria, blood pressure (BP) effects, and anemia after switching to sirolimus (SRL) among renal transplant recipients with CAN versus NEO.

METHODS

Fifty-five kidney transplant recipients with conversion from CNI to SRL owing to CAN or NEO were analyzed for the variables at 6 months before, at the time of, and at 6 months and 1, 2, and 3 years after the switch to SRL.

RESULTS

There were no differences between CAN and NEO in the slope of estimated GFR (mL/min/1.73 m(2) by Cockcroft-Gault formula) at 1 year (-5.5 vs 3.7; P = .007) and at 2 years (-3.86 vs -10.3; P = .01). The values of proteinuria (mg/24 h/1.73 m(2)) before (665 ± 136 vs 329 ± 69; P = .036) as well as at 1 (1,122 ± 306 vs 863 ± 190; P = .478) and at 2 years after conversion (1,360 ± 430 vs 457 ± 154; P = .045) showed some significant differences, as did the use of both antiangiotensin agents, angiotensin-converting enzyme inhibitor and angiotensin receptor blocker at the moment of switch (35% vs 0%; P = .005) at 1 year (69% vs. 6% P = .02) and at 2 years (67% vs 28%; P = .047). There were no differences in graft survival (log rank: P = .515). By logistic regression analysis, the best covariate associated with GFR >45 mL/min at 2 years was GFR >60 mL/min at the moment of switch to SRL (odds ratio, 1.33; 95% confidence interval, 1.002-1.74).

CONCLUSIONS

The evolution of renal damage was more important in the CAN group requiring greater use of 2 angiotensin antagonists for control of proteinuria. We probably need histologic and serologic biomarkers to show which patients with CAN will show a bad evolution after the change to SRL.

Lung cancer and lung transplantation: a review

With the increase in the number of lung transplants, it is expected that there will be a corresponding increase in the number of lung cancers reported in these patients. Longevity of the transplant recipients, lung transplantation for chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis, a history of smoking, and the increasing age of the lung donors make lung cancer more likely. Nodules and masses seen in chest imaging in lung transplant patients call for work up until a final diagnosis is achieved because there is a high likelihood of a serious infection or malignancy. The presence of a native lung is a major risk factor for lung cancer occurring in the transplant setting. Lung cancer of donor origin is rare. Bronchioloalveolar carcinoma confined to one lung can potentially be treated by transplanting the affected lung. Treatment for patients with lung cancer in the lung transplant setting has to be individualized because of the complexity of their medical problems and multiple medications. Attention needs to be focused on detecting lung cancer early in these patients to achieve a favorable outcome.

The role of mTOR inhibitors in the management of posttransplant malignancy

Organ transplant recipients given mammalian target of rapamycin inhibitor (mTORi) have reduced incidence of de novo posttransplant malignancies (dNPTMs). Posttransplant Kaposi's sarcoma and nonmelanotic skin malignancies (NMSC) frequently undergo remission/regression after conversion to mTORi immunosuppression (IS), especially early, small, and low-grade lesions, whereas larger, aggressive, and metastatic skin tumors are less likely to respond. mTORi-based IS is effective and well tolerated in orthotopic liver transplant patients with hepatocellular carcinoma (HCC) achieving excellent survival and disease-free intervals, particularly with extended criteria tumors, although the evidence that mTORi prevents HCC recurrence after orthotopic liver transplantation is only suggestive. Regression of metastatic HCC and other tumors and various forms of posttransplant lymphoproliferative disease have occurred after mTOR conversion. Documentation of regression/remission of other solid-organ dNPTM (colon, stomach, breast, etc.) after mTORi conversion is essentially absent with only anecdotal reports lacking follow-up data. Unfortunately, there is not a single reported prospective clinical trial powered for looking at the effect of mTORi IS in transplant recipients. Nevertheless, reduced incidence of all of dNPTMs and remission/regression of the commonest posttransplant tumors with mTOR therapy are strong reasons to expand the use of mTORi.

Anticancer effect of sirolimus in renal allograft recipients with de novo malignancies

The inhibition of mTOR is a target for anticancer drugs in posttransplant malignancies. The influence of conversion to sirolimus after malignancy diagnosis was investigated on patient and renal allograft survivals. The 20 renal allograft recipients (4 women, 16 men) of ages 26 to 73 years (mean, 59 years) developed malignancies within 6 to 172 months (mean, 53 months) after transplantation. Three patients developed posttransplant lymphoproliferative disease (PTLD); four, Kaposi sarcoma, three, lung cancer; two, malignant melanoma; two, breast cancer; two, renal cell carcinoma; one, Merkel cell carcinoma; one, cutaneous T-cell lymphoma; one, larynx cancer; and one, gingival cancer. After tumor diagnosis, calcineurin inhibitors, azathioprine, or mycophenolate mofetil (MMF) were discontinued abruptly and sirolimus introduced (2 mg/d; target trough level, 4.0 to 8.0 ng/mL). Prednisone was maintained. The observation time of sirolimus therapy was 4 to 48 months (mean, 14 months). Two patients with PTLD (large B-cell lymphoma) and four with Kaposi sarcoma had full regressions. Eleven patients (larynx cancer, melanoma, breast cancer, T-cell lymphoma, renal cell carcinoma, Merkel cell carcinoma, and skin lymphoma) in addition to sirolimus therapy, underwent oncologic treatment, namely, surgery and/or chemotherapy. Six patients died from disseminated malignancy 4 to 9 months after conversion. One patient with T-cell lymphoma lost his graft; in the remaining patients, serum creatinine level was stable. In conclusion, Conversion to sirolimus resulted in regression of large B-cell lymphoma and Kaposi sarcoma. In patients with advanced or disseminated malignancy, the tumors progressed. Graft function was preserved after conversion to sirolimus.

Management of solid tumours in organ-transplant recipients

Malignancy is a well-recognised complication of transplantation and can occur de novo, as a recurrence of a pre-existing malignancy, or from transmission of malignancy from the donor. Common de-novo malignancies are those of the skin and the lymphoreticular system. Various solid-organ cancers have also been reported in transplant recipients and each poses a unique management challenge in view of the unusual setting. We review solid-organ cancers in transplant recipients and their management, including surveillance and prevention.

Evaluation of the efficacy and safety of the conversion from a calcineurin inhibitor to an everolimus-based therapy in maintenance renal transplant patients

Everolimus has recently been introduced into clinical practice with promising perspectives due to its efficacy, lack of nephrotoxicity, and antitumor effects. Experience in clinical trials associated with low-dose cyclosporine showed good results, but there is almost no experience in calcineurin inhibitor (CNI) elimination learning it as the primary immunosuppressant. We describe our experience in a series of 78 stable renal transplant patients who were switched to Everolimus with complete and quick elimination of the CNI: the procedure of conversion, pharmacokinetic results after conversion, evolution of renal parameters (renal function, proteinuria, and others), and safety data (acute rejection and adverse events). An initial dose of 3 mg/d was adequate to obtain the recommended trough levels between 5 and 10 ng/mL. Our results demonstrated that conversion to Everolimus was a simple, safe procedure that must be considered in patients CNI toxicity, especially those with malignant neoplasms and progressive deterioration of renal function due to chronic allograft nephropathy.

Malignant tumors following renal transplantation

A vese és egyéb szervek átültetését követően, többek között a korszerű immunszuppresszív kezelés eredményeként a betegek túlélési ideje egyre növekszik. Ugyanakkor a tartós immunszuppresszió hátrányos következménye, hogy a túlélési idővel arányosan növekszik a rosszindulatú daganatok kialakulásának a valószínűsége is. A fokozott daganatos kockázatért elsősorban az elnyomott immunrendszer tumor- és vírusellenes funkciójának károsodása felelős. A poszttranszplantációs daganatok gyakorisága átlagosan 2–4-szerese a nem transzplantált lakosságénak, és összetétele is eltér a populációra jellemző tumorokétól. Elsősorban azok a daganatok gyakoriak, melyek kialakulásában fontos szerepet tulajdonítunk az onkogén vírusoknak (bőrrák, lymphoma, Kaposi-szarkóma, szájüregi rák, anogenitalis régió tumorai stb.). A szervátültetés utáni daganatok kezelhetősége és prognózisa rosszabb, mint a lakosság hasonló daganataié. A poszttranszplantációs tumorok növekvő gyakoriságuk miatt a transzplantált betegek hosszú távú sorsának egyre fontosabb meghatározó tényezőjévé kezdenek válni. A daganatos kockázat csökkentését segítheti a karcinogén hatások kerülése, a rákmegelőző állapotok és a tumorok korai felismerése és kezelése, az alacsony dózisú immunszuppresszív kezelés, valamint az onkológiai szempontból kedvezőbb hatású, a sejtproliferáció gátlásával ható immunszuppresszív vegyületek alkalmazása.

Conversion to Sirolimus in Posttransplant Renal Neoplasms

BACKGROUND

Calcineurin inhibitors (CNIs) have been associated with the development of posttransplant malignancies, especially lymphoma and solid organ tumors. Sirolimus (SRL) has been shown to inhibit the growth of tumor cell lines in vitro and in vivo and has proven effective in clinical practice for the treatment of Kaposi's sarcoma. Organ transplant patients treated with CNIs who develop a tumor may thus benefit from conversion to SRL.

PATIENTS AND METHODS

From December 2001 to May 2006, 25 patients who developed a tumor were converted from a CNI-based immunosuppressive regimen to SRL. We analyzed the evolution of the tumor, renal function, and the adverse effects resulting from the change of immunosuppression.

RESULTS

The mean follow-up was 19 months. Creatinine clearance (Cockcroft-Gault) increased from 59.5 +/- 21.7 to 66.0 +/- 24.2 mL/min at 12 months (P = .4) and serum cholesterol from 176.7 +/- 46.8 to 216.4 +/- 40.3 mg/dL (P = .01). Proteinuria rose from 0.3 +/- 0.1 to 1.3 +/- 0.9 g/24 hours (P = .004). Adverse events included anemia, thrombocytopenia, and oral ulcers in 20% of cases, cutaneous eruption and gastrointestinal alterations in 12%, and edema in 24%. Four (16%) patients had improved blood pressure readings. Six (24%) patients died and one experienced an acute rejection episode after conversion to SRL. Nineteen (76%) patients displayed a favorable evolution with no evidence of tumor progression.

CONCLUSIONS

Conversion to SRL stabilized tumor progression in 76% of long-term renal transplant patients who developed a neoplasm over a mean follow-up of 19 months. Moreover, renal function improved. The most important adverse effects were increased cholesterol and proteinuria.