Physical Address

304 North Cardinal St.
Dorchester Center, MA 02124

Surgical Management of Patients Considered Marginally Resectable


Summary of Key Points

  • Up to 25% of patients with stage I nonsmall cell lung cancer are considered medically inoperable or high risk for surgery.

  • Therapies such as stereotactic body radiation therapy or ablation offer a less invasive alternative to surgery for marginally resectable patients.

  • Guidelines have been developed to determine fitness for lung cancer surgery (see text).

  • Guidelines to determine optimal therapy (e.g., surgery vs. stereotactic body radiation therapy/ablation) are not well established.

  • The American College of Chest Physicians has determined that patients with a forced expiratory volume in 1 second or percentage of lung diffusion capacity for carbon monoxide less than 40% are at an increased risk for resection.

  • The American College of Surgeons Oncology Group has defined criteria for patients considered to be high-risk for lobectomy but who are still candidates for sublobar resection or nonoperative therapy.

  • Resection is still feasible in such patients defined as high risk.

  • Sublobar resection can be undertaken with low mortality by experienced surgeons.

  • Sublobar resection does not result in significant declines in pulmonary function in high-risk patients.

  • Evaluation in a multidisciplinary setting that includes an experienced thoracic surgeon is recommended when determining therapy for marginally resectable patients.

The standard treatment of stage I nonsmall cell lung cancer (NSCLC) is lobectomy with systematic node dissection. Unfortunately, up to 25% of patients with stage I NSCLC are considered to be medically inoperable or are at high risk for surgery. The increasing use of computed tomography (CT) screening often results in the detection of small tumors. This increase in the number of people with small tumors raises the following question: “What is the appropriate extent of pulmonary resection, particularly in older patients or in patients who, for other reasons, have marginally resectable disease?” The role of sublobar resection is further challenged by the introduction of new techniques associated with low rates of mortality and morbidity, such as stereotactic ablative radiotherapy (SABR) and radiofrequency ablation (RFA).

Which Patients are Considered Marginally Resectable?

Respiratory failure and pulmonary complications represent the most substantial risks following lung resection, and preprocedure risk assessment is based primarily on pulmonary function. Algorithms for differentiating risk levels for patients who are candidates for lung resection have been published. These guidelines provide general cutoffs for additional assessment and suggest threshold values to differentiate low-risk patients from high-risk patients. Cardiac evaluation and lung function testing—including lung diffusion capacity for carbon monoxide (DLCO)—are recommended for every patient who is to have pulmonary resection. Most centers use predictive postoperative forced expiratory volume in 1 second (FEV 1 ) and DLCO. If both values are higher than 30%, resection may still be feasible. According to the American College of Chest Physicians guidelines on the physiologic evaluation of patients for pulmonary resection, patients with an estimated postoperative FEV 1 or DLCO of less than 40% are considered to be at increased risk for postoperative complications. The American College of Surgeons Oncology Group (ACOSOG) has initiated two studies in high-risk patients who have had sublobar resection and patients who are medically inoperable and are treated with RFA. Although the same physiologic criteria were used for both studies ( Table 33.1 ), an important factor was that a credentialed surgeon evaluated patients and deemed each patient to be either a poor candidate for lobectomy but a candidate for a more limited resection or a potential candidate for RFA because the patient was medically inoperable. Criteria that define marginally resectable as contrasted with unresectable are not standardized, and clinical evaluation by an experienced surgeon is essential. Ideally, the cases of all patients who are considered to have marginally resectable disease should be reviewed at a multidisciplinary meeting with an experienced thoracic surgeon participating in the discussion. In some cases of heterogeneous emphysema, pulmonary function may even improve after resection when the tumor is in the most emphysematous zone. This improvement is demonstrated by the results of lung volume–reduction surgery, and patients with this type of disease should not be denied the benefits of a curative lung resection.

TABLE 33.1
Major and Minor Eligibility Criteria in the American College of Surgeons Oncology Group Z4032 Trial a
Major Criteria Minor Criteria
FEV 1 ≤50% FEV 1 , 51% to 60%
DLCO ≤50% DLCO, 51% to 60%
Age ≥75 years
Pulmonary hypertension (defined as pulmonary artery systolic pressure >40 mmHg)
Poor left ventricular function (defined as an ejection fraction ≤40%)
Resting or exercise arterial pO 2 ≤55 mmHg or SpO 2 ≤88%
pCO 2 >45mmHg
Modified Medical Research Council Dyspnea Scale score ≥3
DLCO , lung diffusion capacity for carbon monoxide; FEV 1 , forced expiratory volume in 1 second; pCO 2 , partial pressure of carbon dioxide; pO 2 , partial pressure of oxygen; SpO 2 , peripheral capillary oxygen saturation.

a Eligible patients had to meet one major criterion or two minor criteria.

It is difficult to know how many patients with stage I NSCLC are considered marginally resectable; however, we can get an estimate from some large database studies, such as those using data from the Surveillance, Epidemiology, and End Results (SEER) database. In one study involving 14,555 patients with stage I and II lung cancer, approximately 30% of patients aged 75 years or older were not offered surgery, compared with 8% of patients younger than 65 years. It is unclear how many of these patients were not surgical candidates, and how many, if evaluated by an experienced surgeon, would have been offered sublobar resection. In another analysis of data from the SEER database, 10,761 patients with stage IA NSCLC had resection, with sublobar resection performed in 2234 (20.7%) of these patients.

You're Reading a Preview

Become a Clinical Tree membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here

Related Posts