Survival among solid organ transplant recipients diagnosed with cancer compared to nontransplanted cancer patients-A nationwide study

Cancer mortality among solid organ transplant recipients: A systematic review and meta-analysis

OBJECTIVES

To evaluate the cancer mortality risk among solid organ transplant recipients through a systematic review and meta-analysis.

METHODS

Systematic searches were conducted in PubMed (starting from 1965), ISI Web of Science (starting from 1900), MEDLINE (starting from 1976), and Scopus (starting from 1968) from the inception of each database until July 15, 2024. Studies published in English reporting at least one type of cancer mortality risk among recipients of any type of solid organ transplantation were included. The main outcomes were the standardized mortality ratio (SMR) for cancer mortality in transplant recipients compared to the general population, and the hazard ratio (HR) for cancer mortality in transplant recipients versus cancer patients without prior transplantation.

RESULTS

Solid organ transplant recipients had a 2.06-fold increased cancer mortality risk (SMR, 2.06 [95 % CI, 1.56-2.71]) than the general population. Risks were higher in kidney (SMR 1.92 [95 % CI: 1.30-2.84]), liver (SMR 3.07 [95 % CI: 1.80-5.24]), and lung/heart (SMR 4.87 [95 % CI: 3.33-7.12]) transplant recipients. Cancer patients with prior transplantation had a 1.47-fold increased cancer mortality risk (HR 1.47 [95 % CI: 1.29-1.68]) than those without. East Asia female transplant recipients exhibited higher mortality risks from breast, ovarian, cervix and uterus cancers than those from other regions (SMR 3.13 [95 % CI: 1.93-5.07] vs. 1.16 [95 % CI: 0.88-1.53], P < 0.01).

CONCLUSIONS

Solid organ transplant recipients face significantly higher cancer mortality risks than the general population, highlighting the need for targeted cancer screening and interventions, especially for female solid organ transplant recipients from East Asia.

Previous Solid Organ Transplantation Influences Both Cancer Treatment and Survival Among Colorectal Cancer Patients

Previous solid organ transplantation has been associated with worse survival among colorectal cancer (CRC) patients. This study investigates the contribution of CRC characteristics and treatment-related factors to the differential survival. Using the Swedish register-linkage CRCBaSe, all patients with solid organ transplantation before CRC diagnosis were identified and matched with non-transplanted CRC patients. Associations between transplantation history and clinical CRC factors and survival were estimated using the Kaplan-Meier estimator and logistic, multinomial, and Cox regression, respectively. Ninety-eight transplanted and 474 non-transplanted CRC patients were followed for 5 years after diagnosis. Among patients with stage I-III cancer, transplanted patients had lower odds of treatment with abdominal surgery [odds ratio (OR):0.27, 95% confidence interval (CI):0.08-0.90], than non-transplanted patients. Among those treated with surgery, transplanted colon cancer patients had lower odds of receiving adjuvant chemotherapy (OR:0.31, 95% CI:0.11-0.85), and transplanted rectal cancer patients had higher rate of relapse (hazard ratio:9.60, 95% CI:1.84-50.1), than non-transplanted patients. Five-year cancer-specific and overall survival was 56% and 35% among transplanted CRC patients, and 68% and 57% among non-transplanted. Accordingly, transplanted CRC patients were treated less intensely than non-transplanted patients, and had worse cancer-specific and overall survival. These patients might benefit from multidisciplinary evaluation including transplantation specialists.

Cancer mortality after kidney transplantation: A multicenter cohort study in Italy

Kidney transplant (KT) recipients are known to be at risk of developing several cancer types; however, cancer mortality in this population is underinvestigated. Our study aimed to assess the risk of cancer death among Italian KT recipients compared to the corresponding general population. A cohort study was conducted among 7373 individuals who underwent KT between 2003 and 2020 in 17 Italian centers. Date and cause of death were retrieved until 31 December 2020. Indirect standardization was used to estimate standardized mortality ratios (SMRs) and corresponding 95% confidence intervals (CIs). Cancer was the most common cause of death among the 7373 KT recipients, constituting 32.4% of all deaths. A 1.8-fold excess mortality (95% CI: 1.59-2.09) was observed for all cancers combined. Lymphomas (SMR = 6.17, 95% CI: 3.81-9.25), kidney cancer (SMR = 5.44, 95% CI: 2.97-8.88) and skin melanoma (SMR = 3.19, 95% CI: 1.03-6.98) showed the highest excess death risks. In addition, SMRs were increased about 1.6 to 3.0 times for cancers of lung, breast, bladder and other hematopoietic and lymphoid tissues. As compared to the general population, relative cancer mortality risk remained significantly elevated in all age groups though it decreased with increasing age. A linear temporal increase in SMR over time was documented for all cancers combined (P < .01). Our study documented significantly higher risks of cancer death in KT recipients than in the corresponding general population. Such results support further investigation into the prevention and early detection of cancer in KT recipients.

Expression of miR-92a is associated with the prognosis in non-small cell lung cancer: An observation study

With the development of molecular biology technology, the discovery of microRNAs (miRNAs) has provided new ideas for the diagnosis, treatment, and prognosis of lung cancer and laid a foundation for the study of this malignancy. To assess the potential prognostic value of miR-92a as a new biomarker in non-small cell lung cancer (NSCLC) via clinical evaluation, a total of 100 patients with NSCLC admitted to the Respiratory and Intensive Care Department of Suining Central Hospital in Sichuan Province between August 2007 and April 2020 were retrospectively analyzed. The correlation between miR-92a expression and prognosis of patients with NSCLC was also evaluated in the present study. The expression level of miR-92a was measured by PT-PCR and in situ hybridization. Chi-square test was adopted to explore the relationship of miR-92a expression and clinical features. Kaplan-Meier survival curves were plotted to delineate the overall survival rate of patients with NSCLC. Cox regression analysis was performed to evaluate the prognostic significance of miR-92a expression in NSCLC. The miR-92a expression in NSCLC tissue samples was significantly higher than that in normal lung tissues (P < .001) and significantly correlated with the Eastern Cooperative Oncology Group score, histological type, and distant metastasis (P < .05). Survival curve revealed that patients with NSCLC and high miR-92a expression had relatively higher mortality than those with low PAK4 expression (P = .001). Cox regression analysis explained that miR-92a expression was associated with the prognosis of patients with NSCLC (HR = 1.8, 95% CI: 1.0-3.2, P = .036). In summary, miR-92a was highly expressed in NSCLC tissues and could act as a prognostic factor for patients with NSCLC. These results illustrate that miR-92a expression plays an important role in the invasion and metastasis of NSCLC, and miR-92a can be used as a new biomarker to determine the prognosis of this cancer.

Cumulative exposure to tacrolimus and incidence of cancer after liver transplantation

Cancer is the leading cause of death after liver transplantation (LT). This multicenter case-control nested study aimed to evaluate the effect of maintenance immunosuppression on post-LT malignancy. The eligible cohort included 2495 LT patients who received tacrolimus-based immunosuppression. After 13 922 person/years follow-up, 425 patients (19.7%) developed malignancy (cases) and were matched with 425 controls by propensity score based on age, gender, smoking habit, etiology of liver disease, and hepatocellular carcinoma (HCC) before LT. The independent predictors of post-LT malignancy were older age (HR = 1.06 [95% CI 1.05-1.07]; p < .001), male sex (HR = 1.50 [95% CI 1.14-1.99]), smoking habit (HR = 1.96 [95% CI 1.42-2.66]), and alcoholic liver disease (HR = 1.53 [95% CI 1.19-1.97]). In selected cases and controls (n = 850), the immunosuppression protocol was similar (p = .51). An increased cumulative exposure to tacrolimus (CET), calculated by the area under curve of trough concentrations, was the only immunosuppression-related predictor of post-LT malignancy after controlling for clinical features and baseline HCC (CET at 3 months p = .001 and CET at 12 months p = .004). This effect was consistent for de novo malignancy (after excluding HCC recurrence) and for internal neoplasms (after excluding non-melanoma skin cancer). Therefore, tacrolimus minimization, as monitored by CET, is the key to modulate immunosuppression in order to prevent cancer after LT.

Post-transplant Malignancies Show Reduced T-cell Abundance and Tertiary Lymphoid Structures as Correlates of Impaired Cancer Immunosurveillance

PURPOSE

An increased risk to develop cancer is one of the most challenging negative side effects of long-term immunosuppression in organ transplant recipients and impaired cancer immunosurveillance is assumed as underlying mechanism. This study aims to elucidate transplant-related changes in the tumor immune microenvironment (TME) of cancer.

EXPERIMENTAL DESIGN

Data from 123 organ transplant recipients (kidney, heart, lung, and liver) were compared with historic data from non-immunosuppressed patients. Digital image analysis of whole-section slides was used to assess abundance and spatial distribution of T cells and tertiary lymphoid structures (TLS) in the TME of 117 tumor samples. Expression of programmed cell death 1 ligand 1 (PD-L1) and human-leucocyte-antigen class I (HLA-I) was assessed on tissue microarrays.

RESULTS

We found a remarkably reduced immune infiltrate in the center tumor (CT) regions as well as the invasive margins (IM) of post-transplant cancers. These differences were more pronounced in the IM than in the CT and larger for CD8+ T cells than for CD3+ T cells. The Immune-score integrating results from CT and IM was also lower in transplant recipients. Density of TLS was lower in cancer samples of transplant recipients. The fraction of samples with PD-L1 expression was higher in controls whereas decreased expression of HLA-I was more common in transplant recipients.

CONCLUSIONS

Our study demonstrates the impact of immunosuppression on the TME and supports impaired cancer immunosurveillance as important cause of post-transplant cancer. Modern immunosuppressive protocols and cancer therapies should consider the distinct immune microenvironment of post-transplant malignancies.

The impact of cancer on the risk of death with a functioning graft of Italian kidney transplant recipients

This study assessed the impact of cancer on the risk of death with a functioning graft of kidney transplant (KT) recipients, as compared to corresponding recipients without cancer. A matched cohort study was conducted using data from a cohort of 13 245 individuals who had undergone KT in 17 Italian centers (1997-2017). Cases were defined as subjects diagnosed with any cancer after KT. For each case, two controls matched by gender, age, and year at KT were randomly selected from cohort members who were cancer-free at the time of diagnosis of the index case. Overall, 292 (20.5%) deaths with a functioning graft were recorded among 1425 cases and 238 (8.4%) among 2850 controls. KT recipients with cancer had a greater risk of death with a functioning graft (hazard ratio, HR = 3.31) than their respective controls. This pattern was consistent over a broad range of cancer types, including non-Hodgkin lymphoma (HR = 33.09), lung (HR = 20.51), breast (HR = 8.80), colon-rectum (HR = 3.51), and kidney (HR = 2.38). The survival gap was observed throughout the entire follow-up period, though the effect was more marked within 1 year from cancer diagnosis. These results call for close posttransplant surveillance to detect cancers at earlier stages when treatments are more effective in improving survival.

Colorectal Cancer after Kidney Transplantation: A Screening Colonoscopy Case-Control Study

The incidence of colorectal cancer in kidney transplant recipients has been previously reported with conflicting results. In this study, we investigated if the incidence of colorectal advanced neoplasms in kidney transplant recipients, evaluated with screening colonoscopy, was higher than in healthy individuals. One-hundred sixty kidney transplant recipients undergoing screening colonoscopy were compared with 594 age- and sex-matched healthy individuals. Advanced colorectal neoplasia was found in 22 patients (13.7%), including four patients (2.5%) with colorectal cancer. Compared with the healthy population, kidney transplant recipients did not have an increased risk of developing a colorectal cancer (OR 0.69; 95% CI 0.236–2.063, p = 0.688) although it developed at a younger age. In contrast, kidney transplant recipients had a higher risk of developing an advanced adenoma compared with the control group (OR 1.65; 95% CI 0.930–2.981, p = 0.04). In conclusion, kidney transplant recipients did not have an increased incidence of colorectal cancer compared with healthy population. However, transplant patients displayed a higher incidence of colorectal adenomas, suggesting that screening colonoscopy in kidney transplant recipients should be expanded to include even younger recipients (<50 years old).

Sex differences in cancer risk and outcomes after kidney transplantation

Kidney transplant recipients (KTRs) experience a two- to four-fold increased risk of developing and dying from cancer compared with the general population. High cancer risk results from the interaction of both modifiable and non-modifiable factors. This mapping review explores the impact of sex disparity on cancer's increased incidence and mortality after kidney transplantation (KT). In terms of age, population-based studies indicate that younger recipients of both sexes experience a higher risk of cancer, but this is more pronounced in young women. On the contrary, older men are more likely to be diagnosed with cancer, although their increased risk is not statistically significant compared with the general population. Regarding cancer type, studies show an increased risk of Kaposi sarcoma, gynecologic and lung cancer in women, and bladder and kidney cancer in men. Immune-related cancers such as pos-transplant lymphoproliferative disorders and melanoma are increased in both sexes. Mortality also shows differences between sexes. Although cancer is the second cause of death in both male and female KTRs, studies show higher overall mortality in men and elderly recipients. However, the relative risk of cancer mortality compared with the general population is higher at a younger age, with disparate results regarding sex. Female KTRs appear to die at a younger age than males when compared with the general population. Differences in cancer rates by sex after renal transplantation need further studies. A better understanding of sex-specific differences in cancer epidemiology after KT could help nephrologists to better address pre-transplant counseling, to establish early surveillance programs, and to plan modifiable risk factors such as immunosuppression.

The role of radiotherapy in patients with solid tumours after solid organ transplantation: a systematic review

For patients diagnosed with cancer who have previously received an organ transplant, radiotherapy represents a challenging clinical scenario without well established care algorithms. Immunosuppressive therapy can be a cause for concern among clinicians treating this category of patients. Potential immune modulation following irradiation could affect recipient organ tolerance and the outcomes of the transplantation itself. The main aim of this systematic review was to define the safety and effectiveness of radiotherapy in patients diagnosed with cancer who have previously received an organ transplant. We searched PubMed and Embase for articles published between Jan 1, 1995, and April 30, 2020 for studies in patients who had undergone radiotherapy for post-transplantation malignancies. The Review is framed by the PICO (population, intervention, control, and outcomes) criteria, and primarily focuses on modern treatment techniques.

De-novo malignancies after kidney transplantation: A long-term observational study

Background

De-novo malignancies after kidney transplantation represent one major cause for mortality after transplantation. However, most of the studies are limited due to small sample size, short follow-up or lack of information about cancer specific mortality.

Methods

This long-term retrospective analysis included all adult patients with complete follow-up that underwent kidney transplantation between 1995 and 2016 at our centre. All patients with diagnosis of malignancy excluding non-melanoma skin cancer (NMSC) were identified and a matched control group was assigned to the kidney transplant recipients with post-transplant malignancies.

Results

1417 patients matched the inclusion criteria. 179 malignancies posttransplant were diagnosed in 154 patients (n = 21 with two, n = 2 patients with three different malignancies). Mean age at cancer diagnosis was 60.3±13.3 years. Overall incidence of de-novo malignancies except NMSC was 1% per year posttransplant. Renal cell carcinoma was the most common entity (n = 49, incidence 4.20 per 1000 patient years; cancer specific mortality 12%), followed by cancer of the gastro-intestinal tract (n = 30, 2.57; 50%), urinary system (n = 24, 2.06; 13%), respiratory system (n = 18, 1.54; 89%), female reproductive system (n = 15, 1.29; 13%), posttransplant lymphoproliferative disorders and haematological tumours (n = 14, 1.20; 21%), cancers of unknown primary (n = 7, 0.60 100%) and others (n = 22, 1.89; 27%). Male sex, re-transplantation and time on dialysis were associated with de-novo malignancies after transplantation.

Conclusion

De-novo malignancies continue to be a serious problem after kidney transplantation. To improve long-term outcome after Kidney transplantation, prevention and cancer screening should be more tailored and intensified.

Waiting times in renal transplant candidates with a history of malignancy: time for a change?

PURPOSE OF REVIEW

With the aging population of kidney transplant candidates, a history of malignancy is an increasingly prevalent finding. Tumors can constitute a contraindication for transplantation or can lead to a delay of acceptance to the waiting-list. Current waiting time guidelines mainly refer to early data collected nearly 30 years ago, when the knowledge on tumors was, by current standards, still limited.

RECENT FINDINGS

Today, cancers can usually be divided into many different biological subtypes, according to histological and molecular subclassification and the availability of genetic testing. A more precise stratification and targeted antitumor therapies have led to better therapy outcomes or even cures from certain malignancies and to a better appreciation of tumor risks for the patient.

SUMMARY

Even though transplant patients do have an increased risk for malignancies, it is often overlooked that patients, while on dialysis, are equally prone to develop a tumor. Competing risks (e.g. cardiovascular, mortality risks) through prolonged time on dialysis have to be equally considered, when the decision for acceptance of a patient to the waiting-list is made. Current waiting time suggestions should be critically reconsidered for every patient after a thorough discussion with an oncologist, including new diagnostic and therapeutic strategies, as well as novel risk stratifications.

Head and neck squamous cell carcinoma in solid organ transplant recipients

PURPOSE

Characterize head and neck squamous cell carcinomas in solid transplant recipients and compare outcomes with non-transplanted population.

METHODS

We carried a retrospective cohort analysis in a tertiary care center in Madrid, Spain. The study reviews 26 cases of non-cutaneous HNSCC diagnosed in solid organ transplant recipients between 2000 and 2017. We select a cohort of 130 (1:5) non-transplanted patients among all non-transplanted patients diagnosed during the same period for comparison purposes, through hierarchical clustering analysis. Univariate, overall and specific survival analysis and multivariate Cox proportional hazards regression were used to evaluate our objectives.

RESULTS

The overall risk of non-cutaneous HNSCC in solid transplant recipients was 7.2 cases per 1000. Alcohol abuse (p = 0.021) and upfront surgery (p = 0.019) were more likely to occur in transplanted patients. Age > 60 was an independent predictor of worse outcomes both for overall (HR = 2.4, p < 0.001) and specific (HR = 2.1, p = 0.012) survival. Transplant significantly worse overall survival (HR = 2.1, p = 0.012) but no statistical significant differences were observed on specific survival (p = 0.392).

CONCLUSIONS

Solid organ transplant recipients have a higher risk of suffering non-cutaneous HNSCC. The higher mortality rate of these patients does not appear to be directly related to suffering from head and neck cancer, although it seems to contribute to developing other fatal complications in these fragile patients.

Cancer morbidity and mortality after pediatric solid organ transplantation-a nationwide register study

BACKGROUND

The prevalence of malignancies after pediatric solid organ transplantation was evaluated in a nationwide study.

METHODS

All patients who had undergone kidney, liver, or heart transplantation during childhood between the years 1982 and 2015 in Finland were identified. The inclusion criteria were age under 16 years at transplantation and age over 18 years at the last follow-up day. A total of 233 (137 kidney, 53 liver, and 43 heart) transplant recipients were enrolled. Controls (n = 1157) matched by the year of birth, gender, and hometown were identified using the Population Register Center registry. The cancer diagnoses were searched using the Finnish Cancer Registry.

RESULTS

Altogether 26 individuals diagnosed with cancer were found, including 18 transplant recipients. Cancer was diagnosed at a median of 12.0 (IQR 7.8-17.8) years after the transplantation. The transplant recipients' risk for cancer was significantly higher when compared with the controls (HR 14.7; 95% CI 6.4-33.9). There was no difference for different graft types. Sixty-one percent of cancers among the transplant recipients were diagnosed at age older than 18 years.

CONCLUSION

The risk for cancer is significantly higher among young adults having undergone solid organ transplantation during childhood in comparison with population controls. Careful follow-up and attention to prevent cancers throughout adulthood are warranted.

De Novo Cancer Incidence and Prognosis After Kidney Transplantation: A Single Center Analysis

BACKGROUND

Malignancy is an important cause of mortality in renal transplants recipients. The aim of this study was to evaluate the incidence, prognosis, and survival of patients developing a de novo post-transplant cancer.

METHODS

Using a retrospective cohort design, we evaluated the incidence of de novo cancers among kidney transplants patients in our hospital from January 2000 to December 2012. We also evaluated the patient survival after tumor diagnosis.

RESULTS

We included 535 kidney transplants recipients with a mean follow-up of 7.8 years; among them, 39 (7.2%) developed malignancies. Median time from transplant to cancer diagnosis was 3 years, with a median age at diagnosis of 60 years. Male patients were significantly older at time of cancer diagnosis (68.5 years) compared with women (38 years, P < .05), and cancer diagnosis occurred significantly earlier in men (3.5 years since transplantation) than in women (8.5 years, P < .05). Among 39 patients affected by a de novo post-transplant cancer, 18 patients (46.2%) died, with an average age at death of 58.5 years. The average time from cancer diagnosis to death was 1.5 years. Among the group of patients who did not develop a post-transplant cancer, 83 patients (16.7%) died, with a median age at time of death of 54.5 years (P < .05).

CONCLUSIONS

Kidney transplant recipients are at higher risk of developing a post-transplant cancer. Prognosis after cancer diagnosis is poor, probably as a consequence of a more aggressive behavior of cancer in transplant recipients. Intensive screening protocols could allow for an earlier diagnosis thereby improving the long-term outcome of these patients.

Elevated incidence of head and neck cancer in solid organ transplant recipients

BACKGROUND

Solid organ transplant recipients are known to be at an increased risk of cancer development, but research on head and neck cancer in transplant recipients has been limited and prior risk assessments may not be accurate.

METHODS

A retrospective review using a national Veterans Administration database to query outpatient problem lists for ICD codes indicating solid organ transplant and subsequent diagnosis of head and neck cancer.

RESULTS

In a study of 30 939 656 patients (37 969 solid organ transplants and 113 995 head and neck cancers), history of transplant significantly predicted head and neck cancer, with relative risks ranging from 1.85 (thyroid) to 2.91 (salivary gland). Worse overall survival (OS) was seen for head and neck cancer patients with prior transplants.

CONCLUSIONS

In a large case-control study, prior transplant was a risk factor for head and neck cancer development and worse OS for head and neck cancer patients.

Incidence and Mortality of Renal Cell Carcinoma after Kidney Transplantation: A Meta-Analysis

Background: The incidence and mortality of renal cell carcinoma (RCC) after kidney transplantation (KTx) remain unclear. This study’s aims were (1) to investigate the pooled incidence/incidence trends, and (2) to assess the mortality/mortality trends in KTx patients with RCC. Methods: A literature search was conducted using the MEDLINE, EMBASE and Cochrane databases from inception through October 2018. Studies that reported the incidence or mortality of RCC among kidney transplant recipients were included. The pooled incidence and 95% CI were calculated using a random-effect model. The protocol for this meta-analysis is registered with PROSPERO; no. CRD42018108994. Results: A total of 22 observational studies with a total of 320,190 KTx patients were enrolled. Overall, the pooled estimated incidence of RCC after KTx was 0.7% (95% CI: 0.5–0.8%, I² = 93%). While the pooled estimated incidence of de novo RCC in the native kidney was 0.7% (95% CI: 0.6–0.9%, I² = 88%), the pooled estimated incidence of RCC in the allograft kidney was 0.2% (95% CI: 0.1–0.4%, I² = 64%). The pooled estimated mortality rate in KTx recipients with RCC was 15.0% (95% CI: 7.4–28.1%, I² = 80%) at a mean follow-up time of 42 months after RCC diagnosis. While meta-regression analysis showed a significant negative correlation between year of study and incidence of de novo RCC post-KTx (slopes = −0.05, p = 0.01), there were no significant correlations between the year of study and mortality of patients with RCC (p = 0.50). Egger’s regression asymmetry test was performed and showed no publication bias in all analyses. Conclusions: The overall estimated incidence of RCC after KTX was 0.7%. Although there has been a potential decrease in the incidence of RCC post-KTx, mortality in KTx patients with RCC has not decreased over time.