De novo tumors after liver transplantation: a single-center experience

Post-transplant malignancies in alcoholic liver disease

Post-transplant malignancy is emerging as an important cause of mortality in patients with cirrhosis undergoing liver transplant (LT). However, establishing the exact relationship between the two needs further evaluation. It has been observed that approximately 30% deaths after 10 years of hepatic transplantation occur due to de novo malignancies. Various known risk factors include immunosuppression, age of patient, alcoholic liver disease (ALD) or primary sclerosing cholangitis, smoking, and oncogenic viral infections. There is scanty literature on the post-transplant malignancy risk in patients with alcoholic cirrhosis. The current evidence suggests a particularly increased risk of oropharyngeal and lung cancers in patients transplanted for ALD. Abstinence from alcohol, smoking and other tobacco-containing products along with optimization of immunosuppression are paramount for decreasing the risk of post-transplant malignancies.

Incidence, risk factors and outcomes of de novo malignancies post liver transplantation

Liver transplantation (LT) is associated with a 2 to 7 fold higher, age and gender adjusted, risk of de novo malignancy. The overall incidence of de novo malignancy post LT ranges from 2.2% to 26%, and 5 and 10 years incidence rates are estimated at 10% to 14.6% and 20% to 32%, respectively. The main risk factors for de novo malignancy include immunosuppression with impaired immunosurveillance, and a number of patient factors which include; age, latent oncogenic viral infections, tobacco and alcohol use history, and underlying liver disease. The most common cancers after LT are non-melanoma skin cancers, accounting for approximately 37% of de novo malignancies, with a noted increase in the ratio of squamous to basal cell cancers. While these types of skin cancer do not impact patient survival, post-transplant lymphoproliferative disorders and solid organ cancer, accounting for 25% and 48% of malignancies, are associated with increased mortality. Patients developing these types of cancer are diagnosed at more advanced stages, and their cancers behave more aggressively compared with the general population. Patients undergoing LT for primary sclerosing cholangitis (particularly with inflammatory bowel disease) and alcoholic liver disease have high rates of malignancies compared with patients undergoing LT for other indications. These populations are at particular risk for gastrointestinal and aerodigestive cancers respectively. Counseling smoking cessation, skin protection from sun exposure and routine clinical follow-up are the current approach in practice. There are no standardized surveillance protocol, but available data suggests that regimented surveillance strategies are needed and capable of yielding cancer diagnosis at earlier stages with better resulting survival. Evidence-based strategies are needed to guide optimal surveillance and safe minimization of immunosuppression.

Risk of colorectal carcinoma in post-liver transplant patients: a systematic review and meta-analysis

Liver transplant patients (LTx) have an increased risk for developing de novo malignancies, but for colorectal cancer (CRC) this risk is less clear. We aimed to determine whether the CRC risk post-LTx was increased. A systematic search was performed in MEDLINE and Cochrane databases to identify studies published between 1986 and 2008 reporting on the risk of CRC post-LTx. The outcomes were (1) CRC incidence rate (IR per 100,000 person-years (PY)) compared to a weighted age-matched control population using SEER and (2) relative risk (RR) for CRC compared to the general population. If no RR data were available, the RR was estimated using SEER. Twenty-nine studies were included. The overall post-LTx IR was 119 (95% CI 88-161) per 100,000 PY. The overall RR was 2.6 (95% CI 1.7-4.1). The non-primary sclerosing cholangitis (PSC) IR was 129 per 100,000 PY (95% CI 81-207). Compared to SEER (71 per 100,000 PY), the non-PSC RR was 1.8 (95% CI 1.1-2.9). In conclusion, the overall transplants and the subgroup non-PSC transplants have an increased CRC risk compared to the general population. However, in contrast to PSC, non-PSC transplants do not need an intensified screening strategy compared to the general population until a prospective study further defines recommendations.

Risk of malignant neoplasms after liver transplantation: a population-based study

Posttransplant malignancies have become a serious long-term complication after liver transplantation. Our aim was to compare the incidence of posttransplant cancers with national cancer incidence rates. The study included all Finnish liver transplant patients transplanted at the Helsinki University Central Hospital between 1982 and 2005. The cohort was linked with the nationwide Finnish Cancer Registry. Observed numbers of cancers were compared to site-specific expected numbers based on national cancer incidence rates stratified by age, sex, and calendar time. The standardized incidence ratios (SIRs) were calculated as observed-to-expected ratios. Thirty-nine posttransplant de novo cancers and 11 basal cell carcinomas were found in the cohort of 540 patients during 3222 person years of follow-up. The overall SIR was 2.59 (95% confidence interval 1.84-3.53). SIR was higher for males (SIR 4.16) than for females (SIR 1.74), higher among children (SIR 18.1) than among adults (SIR 5.77 for ages of 17-39 years and 2.27 for ages >/= 40 years), and more elevated in the immediate posttransplant period (SIR 3.71 at < 2 years) compared to later periods (SIR 2.46 at 2-10 years and 1.53 at >10 years). The most common cancer types were nonmelanoma skin cancer (SIR 38.5) and non-Hodgkin lymphoma (SIR 13.9). Non-Hodgkin lymphoma was associated with male gender, young age, and the immediate posttransplant period, whereas old age and antibody induction therapy increased skin cancer risk. In conclusion, cancer incidence is increased among liver transplant patients compared to the general population. This study points out the importance of cancer surveillance after liver transplantation.

Incidence and risk factors for the development of lung tumors after liver transplantation

Tobacco and immunosuppression are risk factors for developing upper aerodigestive and lung tumors after transplantation. This study comprises 701 adult recipients who survived more than 2 months after transplant: 276 patients underwent orthotopic liver transplantation (OLT) for alcoholic cirrhosis (AC) and 425 for nonalcoholic disease. The aim is to analyze the incidence, clinical characteristics, risk factors, and outcome of patients who develop lung malignancies after OLT. Incidence of lung cancer was 2.1% (15 patients): 4.3% (12 patients) in the alcoholic group and 0.7% (three patients) in the nonalcoholic group (P < 0.001). Mean time from OLT to tumor diagnosis was 86 months. Thirteen patients were smokers; 12 patients were heavy drinkers; and 11 were drinkers and smokers. Squamous cell carcinoma was diagnosed in nine patients, large cell carcinoma in three, adenocarcinoma in two, and broncoalveolar in one. Tumor staging: 10 patients at stage IV; three at stage IIIB; and two at stage IIB. Tumor resection was performed in one patient, and three also received chemotherapy. Mean survival after tumor diagnosis was 5.4 months. There is a higher risk of lung cancer in smoker patients who have undergone OLT for AC, and have a very poor prognosis because tumors are diagnosed at advanced stages.

Bronchogenic carcinoma in solid organ transplant recipients

Malignancies are increased in some types of solid organ transplant patients receiving immunosuppressive therapy and are a significant contributor to patient morbidity and mortality. There may be a 100-fold increase in the incidence of de novo neoplasia in this population. The risk of lymphoproliferative malignancies is well appreciated. In contrast, the risk of solid tumors with their consequent morbidity and mortality is less well known, probably because of their common occurrence in the general population. Lung cancer is the most common cause of cancer death in the United States; therefore, lung cancer in patients undergoing organ transplantation would be expected to occur frequently on the basis of chance alone. However, the lung cancer risk is approximately 20 to 25 times that of the general population, with an incidence of 0.28% to 4.1% in patients after heart and lung transplant. Risk factors thought to contribute include cigarette smoking, advanced age at transplantation, and chronic immunosuppressive therapy. The role of transplantation (and consequent therapy) in the development of lung cancer in this high-risk population remains unclear. As in the nontransplant population, adequate screening techniques are lacking, making early diagnosis and treatment a challenge. Despite close follow-up and routine imaging with chest radiography and CT, lung cancers continue to be discovered incidentally and at advanced stages. Treatment is similar to that of patients who are nontransplanted with similar stage, histology, and performance status.

Incidence and risk factors for cancer after liver transplantation

De novo tumors (DNT) are a serious complication after orthotopic liver transplantation (OLT), showing a higher overall incidence ranging from 4.7% to 15.7% in non-selected series. Skin cancer (SC) is the most frequent malignancy observed, ranging from 6% to 70% of the tumors observed, followed by post-transplant lymphoproliferative disorders (PTLD) (4.3-30%). Different immunosuppressive protocols do not seem to influence DNT appearance. Colon and upper aerodigestive cancer after OLT seems to be more prone to develop when there are associated risk factors, such as primary sclerosing cholangitis (PSC) and alcoholic liver cirrhosis (ALC). Some risk factors, such as age, smoking, alcohol and others seem to play a role in higher risk for malignancy, but the presence of a long-term immunosuppressive state, more than the specific regimen used, is the basis for this higher incidence. Ethnic and demographic factors are also important variables influencing the heterogeneity of the results, especially influencing Kaposi's sarcoma and skin tumors.

Update on post-liver transplantation infections, malignancies, and surgical complications

Complications of liver transplantation are not limited to acute and chronic rejection, and recurrence of original disease, but include surgical complications, most commonly hepatic artery occlusion, infections, and development of de novo malignancies. In the early posttransplantation period, procurement/preservation injury, non-immunologic injury to the graft during harvesting and implantation, is manifested by centrilobular hepatocyte pallor and cholestasis but rarely leads to significant graft dysfunction. Ischemic complications, such as hepatic artery thrombosis, are more serious complications and may lead to early graft loss or biliary stricture. Infectious complications generally occur in the mid-to-late period after transplantation; cytomegalovirus (CMV) remains a common pathogen. Human herpes 6 virus infection has been implicated in allograft dysfunction, but is usually seen in the setting of co-infection with CMV. De novo malignancies are emerging as a significant cause of mortality after liver transplantation; risk is cumulative, and increases with time posttransplantation. Development of such malignancies in the setting of solid organ transplantation is multifactorial, and is related to individual and regional predispositions to malignancy, pre-transplantation disease states, recipient viral status, and use and intensity of immunosuppression regimens.