Routine computed tomography screening of the chest in high-risk cardiac transplant recipients may improve survival

Lung Cancer in Lung Transplant Recipients: Clinical, Radiologic, and Pathologic Characteristics and Treatment Outcome

OBJECTIVE

This study aimed to investigate clinical and radiologic characteristics of lung cancer in lung transplant recipients and evaluate the treatment course and prognosis.

METHODS

The study included 448 patients who underwent lung transplant between 2005 and 2021. All patients had pretransplant chest computed tomography (CT), 429 patients had posttransplant CT, whereas 19 had no posttransplant CT (median number of posttransplant CT, 6; range, 0-24). Medical records of these patients were reviewed to identify patients who developed lung cancer after lung transplant. Computed tomography and positron emission tomography/CT at the time of lung cancer diagnoses were reviewed to obtain imaging features. Demographics, tumor histology, stages, and survival were compared using Fisher exact test and Wilcoxon rank sum test.

RESULTS

Among 448 lung transplant recipients with a median follow-up of 71.3 months after lung transplant, 15 patients (3.3%) developed posttransplant lung cancer (13 unilateral, 2 bilateral; 10 men, 5 women; median age, 63.1 years; median time from transplantation to cancer diagnosis, 3.1 years). Twelve cancers were in native lung, and 3 were in transplanted lung. The incidence of lung cancer was higher in single lung transplant recipients than in bilateral lung transplant recipients (10.3% vs 0.6%, respectively; P < 0.0001). Imaging manifestations varied according to tumor stages. Among 12 patients treated for lung cancer, 2 patients developed posttreatment acute respiratory distress syndrome. The median survival from cancer diagnosis of cancer was 6.2 months.

CONCLUSIONS

Posttransplant lung cancer was noted in 3% of lung transplant recipients and was more common in unilateral transplant recipients. The prognosis upon diagnosis was poor with rapid clinical deterioration and serious posttreatment complications.

Rapidly progressive pulmonary hypertension and right ventricular failure in a heart and kidney transplant recipient

A 54-year-old man status post heart and kidney transplant presented with dyspnea. Imaging was consistent with lymphangitic carcinomatosis (LC), in the setting of biopsy proven adenocarcinoma. He developed pulmonary hypertension (PH) and died of right ventricular failure (RVF) 3 weeks later. Acute PH with radiographic features of LC in a high-risk patient warrants expedited malignancy investigation.

The role of radiology in addressing the challenge of lung cancer after lung transplantation

The importance of lung cancer as a complication of lung transplantation is increasingly recognised. It may become an important survival-limiting factor in lung transplant patients as management of other complications continues to improve and utilisation of extended criteria donors grows. Radiology can play a key role in tackling this issue at multiple stages in the transplantation pathway and follow-up process. Routine chest CT as part of pre-transplant recipient assessment (and donor assessment if available) can identify suspicious lung lesions with high sensitivity and detect chronic structural lung diseases such as pulmonary fibrosis associated with an increased risk of malignancy post-transplant. Pre-transplant CT also provides a comparison for later CT studies in the assessment of nodules or masses. The potential role of regular chest CT for lung cancer screening after transplantation is less certain due to limited available evidence on its efficacy. Radiologists should be cognisant of how the causes of pulmonary nodules in lung transplant patients may differ from the general population, vary with time since transplantation and require specific recommendations for further investigation/follow-up as general guidelines are not applicable. As part of the multidisciplinary team, radiology is involved in an aggressive diagnostic and therapeutic management approach for nodular lung lesions after transplant both through follow-up imaging and image-guided tissue sampling. This review provides a comprehensive overview of available clinical data and evidence on lung cancer in lung transplant recipients, and in particular an assessment of the current and potential roles of pre- and post-transplant imaging. KEY POINTS: • Lung cancer after lung transplantation may become an increasingly important survival-limiting factor as mortality from other complications declines. • There are a number of important roles for radiology in tackling the issue which include pre-transplant CT and supporting an aggressive multidisciplinary management strategy where lung nodules are detected in transplant patients. • The introduction of routine surveillance chest CT after transplant in addition to standard clinical follow-up as a means of lung cancer screening should be considered.

Neural cell integration into 3D bioprinted skeletal muscle constructs accelerates restoration of muscle function

A bioengineered skeletal muscle construct that mimics structural and functional characteristics of native skeletal muscle is a promising therapeutic option to treat extensive muscle defect injuries. We previously showed that bioprinted human skeletal muscle constructs were able to form multi-layered bundles with aligned myofibers. In this study, we investigate the effects of neural cell integration into the bioprinted skeletal muscle construct to accelerate functional muscle regeneration in vivo. Neural input into this bioprinted skeletal muscle construct shows the improvement of myofiber formation, long-term survival, and neuromuscular junction formation in vitro. More importantly, the bioprinted constructs with neural cell integration facilitate rapid innervation and mature into organized muscle tissue that restores normal muscle weight and function in a rodent model of muscle defect injury. These results suggest that the 3D bioprinted human neural-skeletal muscle constructs can be rapidly integrated with the host neural network, resulting in accelerated muscle function restoration.

3D bioprinting of skeletal muscle using primary human muscle progenitor cells results in correct muscle architecture, but functional restoration in rodent models is limited. Here the authors include human neural stem cells into bioprinted skeletal muscle and observe improved architecture and function in vivo.

Incidence, risk factors and outcome of de novo tumors in liver transplant recipients focusing on alcoholic cirrhosis

Orthotopic liver transplantation (OLT) is an established life-saving procedure for alcoholic cirrhotic (AC) patients, but the incidence of de novo tumors ranges between 2.6% and 15.7% and is significantly increased in comparison with patients who undergo OLT for other etiologies. Tobacco, a known carcinogen, has been reported to be between 52% and 83.3% in AC patients before OLT. Other risk factors that contribute to the development of malignancies are dose-dependent immunosuppression, advanced age, viral infections, sun exposure, and premalignant lesions (inflammatory bowel disease, Barrett’s esophagus). A significantly more frequent incidence of upper aerodigestive (UAD) tract, lung, skin, and kidney-bladder tumors has been found in OLT recipients for AC in comparison with other etiologies. Liver transplant recipients who develop de novo non-skin tumors have a decreased long-term survival rate compared with controls. This significantly lower survival rate is more evident in AC recipients who develop UAD tract or lung tumors after OLT mainly because the diagnosis is usually performed at an advanced stage. All transplant candidates, especially AC patients, should be encouraged to cease smoking and alcohol consumption in the pre- and post-OLT periods, use skin protection, avoid sun exposure and over-immunosuppression, and have a yearly otopharyngolaryngeal exploration and chest computed tomography scan in order to prevent or reduce the incidence of de novo malignancies. Although still under investigation, substitution of calcineurin inhibitors for sirolimus or everolimus may reduce the incidence of de novo tumors after OLT.

Lung cancer and lung transplantation: a review

With the increase in the number of lung transplants, it is expected that there will be a corresponding increase in the number of lung cancers reported in these patients. Longevity of the transplant recipients, lung transplantation for chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis, a history of smoking, and the increasing age of the lung donors make lung cancer more likely. Nodules and masses seen in chest imaging in lung transplant patients call for work up until a final diagnosis is achieved because there is a high likelihood of a serious infection or malignancy. The presence of a native lung is a major risk factor for lung cancer occurring in the transplant setting. Lung cancer of donor origin is rare. Bronchioloalveolar carcinoma confined to one lung can potentially be treated by transplanting the affected lung. Treatment for patients with lung cancer in the lung transplant setting has to be individualized because of the complexity of their medical problems and multiple medications. Attention needs to be focused on detecting lung cancer early in these patients to achieve a favorable outcome.

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.