Lung transplant is the therapy of choice for a growing number of patients with end-stage lung diseases. Patients receiving a lung transplant are faced with many challenges including drug toxicities, infections, and the risk of rejection.1 Despite these challenges, lung transplant may significantly prolong survival and improve quality of life for many patients.
CANDIDATES FOR LUNG TRANSPLANT
Identifying patients who are appropriate candidates for lung transplant is important to achieving favorable transplant outcomes and to maximizing life expectancy for each patient. The most recent edition of International Society for Heart and Lung Transplant (ISHLT) Guidelines for the Selection of Lung Transplant Candidates is an excellent guide to help physicians identify when to refer potential patients and to how to identify patients who are the most likely to benefit from lung transplant.2
Adults with end-stage lung disease are generally candidates for lung transplant if they meet the following criteria:
- A greater than 50% risk of death from lung disease within 2 years if a lung transplant is not performed
- A greater than 80% likelihood of surviving at least 90 days after the lung transplant procedure
- A greater than 80% likelihood of a 5-year survival posttransplant if graft function is preserved.2
These can only be estimated by transplant programs and not by the referring team in most cases.
Once a patient is identified as a candidate for lung transplant, early referral of patients to a lung transplant program has several advantages and is essential for positive outcomes. Early patient referral allows for timely completion of the formal evaluation of candidacy, patient and family education, as well as the opportunity for the patient and family to raise funds or use other resources to overcome financial hurdles. Listing a patient on the transplant waitlist implies that the patient has a limited life expectancy without a lung transplant and that the risk-benefit ratio favors lung transplant since all other medical options have been exhausted.1
NONCANDIDATES FOR LUNG TRANSPLANT
There are very few absolute contraindications to lung transplant. Generally, most transplant centers in the United States agree that contraindications to lung transplant include conditions associated with increased risk of mortality, including:
- A recent history of a major malignancy. Patients with a 2-year, disease-free interval combined with a low predicted risk of recurrence may be considered in certain cases of localized, non-melanoma skin cancer. A 5-year, disease-free survival is strongly suggested in patients with a history of breast, bladder, or kidney cancer as well as in cases of sarcoma, melanoma, lymphoma and certain hematologic disorders.
- The presence of significant dysfunction of another major organ systems including the heart, liver, kidney, or brain unless a combined organ transplant can be considered and performed.
- Significant coronary heart disease not amenable to revascularization or intervention prior to or at the time of lung transplant.
- The presence of an acute medical condition including but not limited to sepsis and acute liver failure.
- Active Mycobacterium tuberculosis and other highly virulent or highly resistant microbes that are poorly controlled pretransplant.
- Severe obesity with a body mass index greater than 35.
- A history of nonadherence to medical therapy, psychiatric or psychological conditions that might lead to nonadherence, poor or limited social support system, and limited functional status not amenable to rehabilitation.
- Current substance abuse or dependence, including illicit substances, alcohol, and tobacco (nicotine-containing substances). Most centers require at least 6 months’ abstinence from illicit substances prior to being added to the lung transplant waitlist.2
Many transplant centers in the US define the age cutoff for lung transplant at 65; however, some centers may consider candidates older than 65. Advanced age by itself should not be considered a contraindication to lung transplant. However, increased age is usually associated with other comorbid conditions that may increase perioperative and long-term morbidity and mortality. As mentioned previously, the number of older candidates for lung transplant has increased. In the US, 29% of the patients on the national waiting list in 2015 were over age 65.4
Past chest surgery
It is not uncommon for lung transplant candidates to have a history of chest surgery such as lung resection, pleurodesis, or coronary artery bypass grafting. The limited literature regarding the outcomes for these patients suggests they may experience higher rates of bleeding, re-exploration, and renal dysfunction.2 However, these patients should not be excluded from lung transplant and successful transplant outcomes have been achieved in this population by experienced centers.5 In candidates with a history of chronic obstructive pulmonary disease (COPD) and lung-volume reduction surgery (LVRS), early case series indicate that these patients did well after lung transplant.6 However, more recent data demonstrate that patients with prior LVRS who undergo lung transplant experience higher rates of bleeding, worse early graft dysfunction, and worse outcomes overall.7 As with lung transplant candidates with previous chest surgery, lung transplant candidates with previous LVRS are best served by experienced transplant centers.
Hepatitis and HIV
Patients with a history of infection with hepatitis B, hepatitis C, or human immunodeficiency virus (HIV) are candidates for lung transplant at centers experienced with lung transplant in patients with these infections. Most centers advocate that patients with a history of hepatitis B or C have viral infection levels that are controlled or reduced as low as possible and that there is no evidence of portal hypertension or severe cirrhosis.8,9 In the case of HIV, patients should have controlled disease with a negative or undetectable viral load and have no current acquired immunodeficiency defining illness.10 Patients colonized with particular species of Burkholderia cepacia or Mycobacterium abscessus subspecies can be considered for lung transplant only at centers with established preoperative and postoperative protocols for these infections due to the increased risk of perioperative mortality associated with these organisms.11,12