Epidemiology of post-transplant malignancy in Chinese renal transplant recipients: a single-center experience and literature review

Genitourinary malignancies in kidney transplant recipients

Advances in immunosuppressive therapy and postoperative management have greatly improved the graft and patient survival rates after kidney transplantation; however, the incidence of post-transplant malignant tumors is increasing. Post-renal transplantation malignant tumors are associated with renal failure, immunosuppression, and viral infections. Moreover, the risk of developing cancer is higher in kidney transplant recipients than in the general population, and the tendency to develop cancer is affected by the background and environment of each patient. Recently, cancer after kidney transplantation has become the leading cause of death in Japan. Owing to the aggressive nature and poor prognosis of genitourinary malignancies, it is crucial to understand their epidemiology, risk factors, and best practices in kidney transplant recipients. This review has a special emphasis on the epidemiology, risk factors, and treatment protocols of genitourinary malignancies in kidney transplant recipients to enhance our understanding of the appropriate management strategies. Optimal immunosuppressive therapy and cancer management for these patients remain controversial, but adherence to the general guidelines is recommended.

Incidence, Risk Factors, and Outcomes of De Novo Malignancy following Kidney Transplantation

Introduction: Post-transplant malignancy is a significant cause of morbidity and mortality following kidney transplantation often emerging after medium- to long-term follow-up. To understand the risk factors for the development of de novo post-transplant malignancy (DPTM), this study aimed to assess the incidence, risk factors, and outcomes of DPTM at a single nephrology centre over two decades. Methods: This retrospective cohort study included 963 kidney transplant recipients who underwent kidney transplantation between January 2000 and December 2020 and followed up over a median follow-up of 7.1 years (IQR 3.9-11.4). Cox regression models were used to identify the significant risk factors of DPTM development, the association of DPTM with graft survival, and mortality with a functioning graft. Results: In total, 8.1% of transplant recipients developed DPTM, and the DPTM incidence rate was 14.7 per 100 patient-years. There was a higher mean age observed in the DPTM group (53 vs. 47 years, p < 0.001). The most affected organ systems were genitourinary (32.1%), gastrointestinal (24.4%), and lymphoproliferative (20.5%). Multivariate Cox analysis identified older age at transplant (aHR 9.51, 95%CI: 2.60-34.87, p < 0.001) and pre-existing glomerulonephritis (aHR 3.27, 95%CI: 1.10-9.77, p = 0.03) as significant risk factors for DPTM. Older age was significantly associated with poorer graft survival (aHR 8.71, 95%CI: 3.77-20.20, p < 0.001). When age was excluded from the multivariate Cox model, DPTM emerged as a significant risk factor for poor survival (aHR 1.76, 95%CI: 1.17-2.63, p = 0.006). Conclusion: These findings underscore the need for tailored screening, prevention, and management strategies to address DPTM in an aging and immunosuppressed kidney transplant population.

Clinical characteristics and treatment outcomes of kidney transplant recipients with de novo urothelial carcinoma: thirty years of experience from a single center

BACKGROUND

De novo urothelial carcinoma (UC) is a leading cause of death after kidney transplant (KT). The efficacy of various treatments, apart from surgery, and the prognosis for patients with urothelial carcinoma after kidney transplantation remain unclear.

METHODS

We retrospectively reviewed the efficacy of chemotherapy with gemcitabine + cisplatin (GC) or gemcitabine + carboplatin (GCa), bladder infusion chemotherapy, and immunosuppression therapy for de novo UC in kidney transplantation recipients at different sites and T stages. We evaluated the prognosis and compared the difference using Kaplan-Meier analysis and the log-rank test.

RESULTS

Of the 97 kidney transplantation recipients with de novo UC, 51 (52.6%) were diagnosed with upper urinary tract carcinoma (UTUC), 17 (17.5%) with bladder carcinoma (BC), and 29 (29.9%) with both UTUC and BC. The five-year survival rates for BC, UTUC, and BC + UTUC with ≤ T1 stage were 100%, 88.2%, and 57.7%, respectively, while the survival rates for UTUC, BC + UTUC with ≥ T2 stage were 90.2% and 48.2%. Cyclosporine A significantly improved progression-free survival (PFS) in UTUC with ≤ T1 stage (p = 0.017). Rapamycin significantly improved PFS in UTUC with ≥ T2 stage (p = 0.026). Bladder infusion chemotherapy and GC/GCa chemotherapy had no significant effect on each T stage and site. Patients with UTUC + BC had the poorest overall survival (OS) compared with those with BC and UTUC.

CONCLUSION

The prognosis of UC in different sites varies. GC/GCa chemotherapy and bladder infusion chemotherapy appear to have no effect on prognosis. Rapamycin can delay the progression of advanced UTUC.

De novo upper tract urothelial carcinoma after renal transplantation: a single-center experience in China

BACKGROUND

Long-term prognosis and risk factors of de novo upper tract urothelial carcinoma after renal transplantation were rarely studied. Thus, the aim of this study was to investigate the clinical features, risk factors, and long-term prognosis of de novo upper tract urothelial carcinoma after renal transplantation, especially the impact of aristolochic acid on tumor, using a large sample.

METHODS

106 patients were enrolled in retrospective study. The endpoints included overall survival, cancer-specific survival, bladder or contralateral upper tract recurrence-free survival. Patients were grouped according to aristolochic acid exposure. Survival analysis was performed using Kaplan-Meier curve. Log-rank test was used to compare the difference. Multivariable cox regression was conducted to evaluate the prognostic significance.

RESULTS

Median time from transplantation to development of upper tract urothelial carcinoma was 91.5 months. Cancer-specific survival rate at 1, 5, 10 years was 89.2%, 73.2%, 61.6%. Tumor staging (≥ T2), lymph node status (N +) were independent risk factors for cancer-specific death. Contralateral upper tract recurrence-free survival rate at 1, 3, 5 years was 80.4%, 68.5%, 50.9%. Aristolochic acid exposure was independent risk factor for contralateral upper tract recurrence. The patients exposed to aristolochic acid had more multifocal tumors and higher incidence of contralateral upper tract recurrence.

CONCLUSION

Both higher tumor staging and positive lymph node status were associated with a worse cancer-specific survival in patients with post-transplant de novo upper tract urothelial carcinoma, which highlighted the importance of early diagnosis. Aristolochic acid was associated with multifocality of tumors and higher incidence of contralateral upper tract recurrence. Thus, prophylactic contralateral resection was suggested for post-transplant upper tract urothelial carcinoma, especially for patients with aristolochic acid exposure.

Bladder paraganglioma after kidney transplantation: A case report

BACKGROUND

Kidney transplantation is associated with an increased risk of tumors in the urinary bladder. Among all the pathological types of tumors in the bladder, paraganglioma, which arises from extra-adrenal paraganglia and consists of chromaffin cells, is rare. Paragangliomas might cause severe clinical symptoms due to catecholamine hypersecretion or mass compression. Bladder paragangliomas are rare, especially those appearing after kidney transplantation. Here, we report a case of bladder paraganglioma developing after kidney transplantation.

CASE SUMMARY

A 63-year-old woman received a kidney transplant 12 years ago and took oral immunosuppressants (cyclosporine, mizoribine, and methylprednisolone) for regular post-transplant treatment. The patient felt no discomfort and she came to the hospital for a routine checkup. A mass located in the bladder was incidentally discovered by computed tomography, and she underwent surgical treatment. A 2 cm × 2 cm invasive mass was found in the trigone of the bladder and the mass was removed. The diagnosis of paraganglioma was confirmed by morphology and immunophenotyping. The patient had a good prognosis and is still alive.

CONCLUSION

Paraganglioma can grow in the bladder, which might cause no clinical symptoms. The diagnosis mainly depends on morphology and immunophenotyping. Surgical resection is an important treatment option for such patients.

Pharmacotherapeutic options for the prevention of kidney transplant rejection: the evidence to date

INTRODUCTION

Although early rejection episodes are successfully controlled, the problem of unrecognized production of de novo anti HLA antibodies and associated chronic rejection still persists.

AREAS COVERED

In addition to the standard induction and maintenance therapy, we present a couple of new drugs as induction (Alemtuzumab), CNI free protocol (Belatacept, Sirolimus, Everolimus), maintenance treatment in transplant patients with various type of malignancies (T cell targeted immunomodulators blocking the immune checkpoints CTLA-4, PD1/PDL1) and TMA (aHUS) -eculizimab, and IL6 receptor antagonists in antibody mediated rejection (AMR).

EXPERT OPINION

There are couple of issues still preventing improvement in kidney transplant long-term outcomes with current and anticipated future immunosuppression: patient more susceptible to infection and CNI nephrotoxicity in kidneys obtained from elderly donors, highly sensitized patients with limited chances to get appropriate kidney and a higher risk for late AMR. A lower rate of CMV/BK virus infections has been observed in everolimus treated patients. Belatacept use has been justified only in EBV seropositive kidney transplants due to the increased risk of PTLD. Eculizumab upon recurrence of aHUS is a sole cost-effective option. A new IL-6 blocking drug (clazakizumab/tocilizumab) is promising option for prevention/treatment of AMR. Clinical experience in tailoring immunosuppression for as long as possible graft and patient survival is inevitable.

De Novo Malignancies after Kidney Transplantation

Cancer is an important outcome after kidney transplantation because it is the second leading cause of death in most Western countries. The excess risk of cancer after transplantation is approximately two to three times higher than the age- and sex-matched general population, driven largely by viral- and immune-related cancers. Once cancer develops, outcomes are generally poor, particularly for those with melanoma, renal cell carcinoma, and post-transplant lymphoproliferative disease. More importantly, effective screening and treatment strategies are limited in this high-risk population. In this review, we begin with a patient's journey that maps the experience of living with a kidney transplant and understand the patient's knowledge, education, and experience of cancer in the context of transplantation. The epidemiology and burden of cancer in recipients of kidney transplants, along with the up-to-date screening and treatment strategies, are discussed. We also focus on the current understanding of optimal care for recipients of kidney transplants who are living with cancer from the patients' perspectives.

Renal Cell Carcinoma and Kidney Transplantation: A Narrative Review

Kidney transplant recipients (KTRs) are at increased risk of developing renal cell carcinoma (RCC). The cancer can be encountered at different steps in the transplant process. RCC found during work-up of a transplant candidate needs treatment and to limit the risk of recurrence usually a mandatory observation period before transplantation is recommended. An observation period may be omitted for candidates with incidentally discovered and excised small RCCs (<3 cm). Likewise, RCC in the donor organ may not always preclude usage if tumor is small (<2 to 4 cm) and removed with clear margins before transplantation. After transplantation, 90% of RCCs are detected in the native kidneys, particularly if acquired cystic kidney disease has developed during prolonged dialysis. Screening for RCC after transplantation has not been found cost-effective. Treatment of RCC in KTRs poses challenges with adjustments of immunosuppression and oncologic treatments. For localized RCC, excision or nephrectomy is often curative. For metastatic RCC, recent landmark trials in the nontransplanted population demonstrate that immunotherapy combinations improve survival. Dedicated trials in KTRs are lacking. Case series on immune checkpoint inhibitors in solid organ recipients with a range of cancer types indicate partial or complete tumor response in approximately one-third of the patients at the cost of rejection developing in ~40%.

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.

Twenty-eight-year incidence and characteristics of post-transplant skin cancers: Comparative analysis of past and recent 10-year experience

Because primary skin cancers in organ transplant recipients are rare, little is known about the characteristics and risk factors for skin cancers in organ transplant recipients. We searched the Asan Medical Center database of 13 469 organ transplant recipients for cases of all skin cancers from January 1990 to December 2018. Characteristics of and risk factors for skin cancers were analyzed and compared according to the period of transplantation. Of the identified 113 patients with skin cancers, squamous cell carcinoma was the most common cancer followed by basal cell carcinoma and Kaposi sarcoma. The cumulative incidence of skin cancers at 28 years was 5.3%. Over the 10-year period from January 2009 to December 2018, the standardized incidence ratio for premalignant in situ skin lesions increased, whereas the standardized incidence ratio for skin cancers decreased. Age at transplantation and treatment with more than two immunosuppressive agents were risk factors for the development of new skin cancers in organ transplant recipients. Over the most recent 10-year period, post-transplant skin cancers have been found earlier and diversified compared with in the previous period.

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.

Lung Cancer in Renal Transplant Recipients

Introduction. Although the incidence of malignancy has increased after solid organ transplantation, data on lung cancer in this group of patients is scarce. The aim of this study was to determine clinical characteristics and outcome of patients who developed lung cancer after renal transplantation. Methods. Among a cohort of 1658 patients who received a transplant at our institution and were followedup between 1973 and 2014, five patients developed lung cancer. We analyzed risk factors, transplantation characteristics, treatment options and survival. Results. Lung cancer was diagnosed in 5 patients (0.3%). Time to diagnosis after the transplant procedure ranged from 26 to 156 months (mean 115 months). All of them had a smoking history. Tumors were classified as IIB (20%), IIIA (40%), and IV (40%). Histological types included adenocarcinoma (80%) and there was one case of sarcomatoid carcinoma (20%). One patient had concomitant thyroid papillary carcinoma. Radiotherapy was applied in 2 patients, 2 underwent chemotherapy (erlotinib and combination of carboplatinum and etopozide in one patient each), and 2 died within one month after the diagnosis from disseminated malignant disease. Patients with stage IIIA survived 14 and 24 months after the diagnosis. The patient with sarcomatoid cancer underwent thoracotomy with a complete resection, lost his graft function and died 7 months after the diagnosis. Conclusion. Lung cancer is relatively rare malignancy in renal transplant recipients, but associated with high mortality. Smoking is a significant risk factor, thus smoking cessation should be promoted among renal transplant recipients, as well as regular screening for lung cancer.

[Primary lung cancer in Chinese renal transplant recipients: a single-center analysis]

OBJECTIVE

To evaluate the clinical characteristics and the outcomes of primary lung cancer in renal recipients.

METHODS

Between January, 1988 and April, 2015, a total of 2793 consecutive patients underwent renal transplantation at our center. Fourteen (0.5%) patients subsequently developed lung cancer, for which 10 (71.4%) received surgical treatment.

RESULTS

The mean age of the 14 patients with post-transplant lung cancer was 50.2±8.3 years at transplantation, and 10 of them (71.4%) were former smokers. In 9 (64.3%) of 14 patients, the malignancies were detected incidentally and 5 patients were symptomatic. The average interval from transplantation to cancer diagnosis was 65.7±20.1 months. Eleven patients died from cancer metastasis or organ failure and 3 remained alive with functioning graft. The survival rates of the patients with lung cancer in different stages were statistically different (P=0.001). The overall 5-year survival rate after diagnosis was 17.9% in these 14 patients.

CONCLUSION

The risk of primary lung cancer might be higher in renal transplant recipients than in the general Chinese population. Routine chest screening for lung cancer in renal transplant recipients may help in early detection and treatment of the malignancy to improve the prognosis.

Association between RECQL5 genetic polymorphisms and susceptibility to breast cancer

Previous studies indicated that the RECQL5 gene polymorphism was associated with human cancers. However, the association of RECQL5 gene polymorphism with breast cancer remains unclear. In the present study, we investigated the association between polymorphisms of the RECQL gene and breast cancer in a Chinese population. We selected four polymorphisms of the RECQL5 gene (rs820186, rs820196, rs820200, and rs4789223) for the present study. The genotyping was performed using the TaqMan method in 510 patients with breast cancer and 510 age- and sex-matched non-cancer controls. We found that rs820196 and rs828200 polymorphisms of RECQL5 were associated with breast cancer. For rs820196, the CC genotype (16.7 vs 9.4 %, P < 0.001) and C allele (42.5 vs 34.3 %, P < 0.001) were common in the breast cancer patients than in the control subjects, respectively. For rs828200, the GG genotype (23.7 vs 18.0 %, P < 0.001) and G allele (52.7 vs 43.8 %, P < 0.001) were common in the breast cancer patients than in the control subjects, respectively. Haplotype analysis showed that C-G (odds ratio (OR) = 2.247, 95 % confidence interval (CI) 1.854∼2.722; P < 0.001) was associated with increased risk for breast cancer. However, the C-T (OR = 0.175, 95 % CI 0.110∼0.278; P < 0.001) and T-G (OR = 0.544; 95 % CI 0.428∼0.692; P < 0.001) were associated with decreased risk for breast cancer, respectively. The present study indicated that the RECQL5 genetic polymorphism and haplotypes were associated with breast cancer in a Chinese population.

Upper tract urothelial carcinomas in patients with chronic kidney disease: relationship with diagnostic challenge

Chronic kidney disease and upper tract urothelial carcinomas display a bidirectional relationship. Review of the literature indicates that early diagnosis and correct localization of upper tract urothelial carcinomas in dialysis patients and kidney transplant recipients are important but problematic. Urine cytology and cystoscopy have limited sensitivity for the diagnosis of upper tract urothelial carcinomas in dialysis patients. Enhanced computed tomography and magnetic resonance imaging could prove useful for the detection and staging of upper tract urothelial carcinomas in dialysis patients. Renal ultrasound can detect hydronephrosis caused by upper tract urothelial carcinomas in kidney transplant recipients but cannot visualize the carcinomas themselves. High detection rates for upper tract urothelial carcinomas in kidney transplant recipients have recently been demonstrated using computed tomography urography, which appears to be a promising tool. To detect carcinomas in dialysis patients and kidney transplant recipients as early as possible, regular screening in asymptomatic patients and diagnostic work-up in symptomatic patients should be performed using a combination of urological and imaging methods. Careful assessment of subsequent recurrence within the contralateral upper urinary tract and the urinary bladder is necessary for dialysis patients and kidney transplant recipients with upper tract urothelial carcinomas.