A wide varieties of malignancies have been reported with increasing incidence among SOT (solid organ transplantation) patients.

DEVELOPMENT OF MALIGNANCY FOLLOWING SOLID ORGAN TRANSPLANTATION

A wide varieties of malignancies have been reported with increasing incidence among SOT (solid organ transplantation) patients. The reported incidence of certain malignancy seems to be related to the type of the transplanted organ. Many risk factors have been related to the increasing incidence of secondary malignancy among organ transplant recipients that may include sun ray’s exposure, potency and longevity of immunosuppression, associated viral infection, and particularly in KTRs (kidney transplant recipients), pre-transplant dialysis.  

 

 

Role of the immunosuppressive agents

Certain evidence suggests that CNI (calcineurin inhibitors) and azathioprine, but not sirolimus may trigger certain risk for cancer development that could be out of the impact of potency and duration of immunosuppression. However, sirolimus, in comparison to other immunosuppressive agents, may confer a lowered risk of cancer evolution. In regard to virology prevalence, 4 culprit viruses may be involved (cocarcinogenic viruses) in organ transplant recipients (TR) that include Epstein-Barr virus (EBV), HHV-8, human papillomavirus (HPV), and the Merkel cell polyomavirus (MCV).  

Donor transmission

Cancer cell unintended transmission via a donated organ is rarely observed, but may induce metastatic cancer cells dissemination in an immunosuppressed TR. However, the risk of cancer cells transmission seems to be primarily dependent on the nature and extent of donor's malignancy.  

The TRs chance to recognize and prevent the evolution of SOT-associated malignancies, especially those with the early developed carcinomas, depends primarily on the serial screening tests and how much adherent were the TRs to the necessary prophylactic precautions.

Therapeutic approach

The general approach to post-transplant cancer may be instituted with the general prophylactic measures, particularly, high burden of immunosuppression or multiple exposures to antilymphocyte agents should be discarded. A meticulous screening for both TRs and donors before transplantation to recognize an underlying tumor should be also considered. Withdrawal or dose reduction of immunosuppressive burden is beneficial primarily for KTRs, as allograft loss due to rejection episodes is not currently fatal in contrary to cancer spread.

Considering these prophylactic measures may induce cancer regression in lymphoma, cutaneous malignancy, Kaposi’s tumors, where cessation/reduction of CNI exposure may be very essential, and also in donor-related tumors.  TRs with a past history of previous cancer, there is a wide variation in the possibility of recurrence according to cancer type that defines the current recommendations for TRs with a pre-existing tumor. The effect of a prior history of cancer on TR management is recognized by the currently available therapeutic alternates.

In KTRs, the following approach has been postulated:

I.        No waiting time for transplant is required with the low-grade risk cancers, as incidental cancers e.g., renal cell carcinoma, in situ carcinoma, primary basal cell skin carcinoma, and low-grade bladder cancer.

II.        Organ transplant should be postponed for at least 5 ys for high risk cancers for recurrence including: melanoma (experts may advice 10 years’ delay), breast, and colorectal cancer. Transplant should be postponed for about 2 years mostly with other types.

III.        Little data is available about cardiac transplant in TRs with a past history of cancer that made a dedicated design for guidelines/recommendations unreachable. A paucity of data was available about TRs whose management of previous cancer seems to be successful that is satisfactory for cardiac transplant candidates.    The requirement of a meticulous investigation for malignancy prior to transplant in TRs with a past history of malignancy, older aged TRs in particular, cannot be directly advised.

N.B. This Blogger is created to declare the risk of malignancy after organ transplantation.

https://www.wjgnet.com/2220-3230/full/v10/i2/29.ht 10.5500/ wjt.v10.i2.29

REFERENCES

 

1.    Park JM, Choi MG, Kim SW, et al. Increased incidence of colorectal malignancies in renal transplant recipients: a case control study. Am J Transplant 2010; 10:2043.

2.    Duman S, Töz H, A��çi G, et al. Successful treatment of post-transplant Kaposi's sarcoma by reduction of immunosuppression. Nephrol Dial Transplant 2002; 17:892.

3.    Sheil AG. Donor-derived malignancy in organ transplant recipients. Transplant Proc 2001; 33:1827.

4.    Leibovich BC, Blute M, Cheville JC, et al. Nephron sparing surgery for appropriately selected renal cell carcinoma between 4 and 7 cm results in outcome similar to radical nephrectomy. J Urol 2004; 171:1066.

5.    Moudouni SM, Tligui M, Doublet JD, et al. Nephron-sparing surgery for de novo renal cell carcinoma in allograft kidneys. Transplantation 2005; 80:865.

6.    Trofe J, Buell JF, Woodle ES, et al. Recurrence risk after organ transplantation in patients with a history of Hodgkin disease or non-Hodgkin lymphoma. Transplantation 2004; 78:972.

7.    Otley CC, Hirose R, Salasche SJ. Skin cancer as a contraindication to organ transplantation. Am J Transplant 2005; 5:2079.

8.    Taylor DO, Farhoud HH, Kfoury G, et al. Cardiac transplantation in survivors of lymphoma: a multi-institutional survey. Transplantation 2000; 69:2112.

9.    Ward KM, Binns H, Chin C, et al. Pediatric heart transplantation for anthracycline cardiomyopathy: cancer recurrence is rare. J Heart Lung Transplant 2004; 23:1040.