Diagnostic imaging of lung cancer after heart transplantation.

Aims And Background: In heart transplant recipients pulmonary neoplasms are among the most frequent solid tumors; they have a rapid and aggressive course, and therefore require an early diagnosis. We describe the role that diagnostic imaging plays in different diagnostic moments of this disease.

Methods: We evaluated the incidence and diagnosis of lung cancer in patients who underwent heart transplants at our institution. Taking into account the few different diagnostic imaging techniques (chest X-ray, high-resolution computed tomography [CT], staging CT and CT-guided biopsy) used in standard surveillance protocols or indicated by clinical symptoms, we evaluated their diagnostic accuracy, their efficacy in tumor staging, and their impact on the therapeutic choices.

Results: Seventeen neoplasms in a total of 712 patients were diagnosed (2.4%). In 16 of these 17 cases chest X-ray (routinely performed as follow-up in 11 cases, indicated by symptoms in 5 cases) was diagnostic. In another 11 cases chest X-ray was false positive. The diagnostic accuracy, sensitivity, specificity, positive and negative predictive value of chest X-ray was 98%, 91%, 98%, 50%, and 99%, respectively. Total-body CT correctly staged the tumors and provided information as to whether surgery was indicated or not (stage II or advanced).

Conclusions: Chest X-ray is still the surveillance radiological technique in heart transplant recipients. Considering its low specificity and sensitivity, we propose high-resolution CT imaging during follow-up to identify pulmonary lesions as soon as possible and enable a differential diagnosis with parenchymal inflammation. The use of CT-guided fine-needle biopsy and culture examinations permits to differentiate neoplastic from inflammatory parenchymal opacities. Use of CT in cancer staging is effective for subsequent treatment choices.