Malignant tumours in lung transplant recipients

Background: Immunosuppression after lung transplantation (LuTx) in patients with end-stage pulmonary disease consists of a fine line between organ tolerance and prevention of infections. Cancer immunosurveillance is considered to comprise crucial immune responses to arising tumour cells and is potentially restricted by immunosuppressive therapy. Objectives: We intended to find out whether there was a predominating tumour entity in LuTx patients including its localisation and time to tumour diagnosis. Methods: We analysed 238 patients after LuTx, regarding occurrence of malignant diseases between 2000 and 2016. We collected data on surgical procedure for Tx, smoking status, immunosuppressive therapy, infections, interval from LuTx to tumour diagnosis, tumour histology, and TNM stage. Results: We identified 13 patients (5.5%, eight men, five women) harbouring 15 tumours diagnosed after LuTx. Of these, pulmonary end-stage diseases consisted of chronic obstructive pulmonary disease, interstitial lung disease, and pulmonary arterial hypertension, in six, six, and one patient, respectively. Lung cancer was found in five transplant lungs (62.5%) and in three native lungs after single LuTx (37.5%). Smoking history was positive in 11 patients (84.6%) including all lung cancer patients. One patient developed three different tumours comprising cancer of the lung, the prostate and the skin. The median interval LuTx to tumour was 4.5 years (range 1.46 – 5.56) and was the shortest for pulmonary tumours compared with extrapulmonary (2.1 vs. 4.0 years, respectively). Conclusion: Lung cancer was the most frequent malignant tumour with the shortest interval LuTx to tumour following LuTx. Its early diagnosis requires thorough post-Tx follow-up.