MKSAP Quiz: Peripheral 9-mm solid pulmonary nodule

A 72-year-old woman is evaluated during a routine visit. She has a 30-pack-year smoking history and quit 5 years ago. A screening low-dose chest CT scan shows a peripheral 9-mm solid pulmonary nodule in the left upper lobe and emphysema. What is the most appropriate management?


A 72-year-old woman is evaluated during a routine visit. She has a 30-pack-year smoking history and quit 5 years ago. She has a history of mild COPD and breast cancer diagnosed 15 years ago, currently in remission. A chest radiograph from 5 years ago showed no signs of disease recurrence. Medications are albuterol and tiotropium inhalers.

On physical examination, vital signs are normal. Lung examination reveals prolonged expiration and diminished breath sounds throughout. The breast examination is unremarkable.

A screening low-dose chest CT scan shows a peripheral 9-mm solid pulmonary nodule in the left upper lobe and emphysema but no mediastinal or hilar lymphadenopathy and no pleural effusion. A PET/CT scan using fluorodeoxyglucose (FDG) is performed and the nodule is intensely hypermetabolic. There is no evidence of distant uptake.

Which of the following is the most appropriate management?

A. Bronchoscopy with biopsy
B. Serial chest CT scans
C. Surgical wedge resection
D. Transthoracic needle aspiration


MKSAP Answer and Critique

The correct answer is C. Surgical wedge resection. This content is available to MKSAP 18 subscribers as Question 35 in the Pulmonary and Critical Care section. More information about MKSAP is available online.

Definitive treatment is recommended for this patient and, therefore, a surgical wedge resection is appropriate. She has several risk factors for malignancy, including age, size of the nodule, upper-lobe location of the nodule, smoking history, and history of malignancy. In addition, the PET/CT scan showed fludeoxyglucose avidity, confirming the high probability of malignancy but without evidence of distant metastasis. As with subcentimeter nodules, the availability of previous imaging of the chest to assess the stability or growth of these lesions is helpful. An enlarging or new pulmonary nodule warrants more aggressive evaluation with tissue diagnosis or excision depending on the nodule's pretest probability of malignancy. The first step when evaluating a solid pulmonary nodule that is larger than 8 mm is to estimate the probability of malignancy. This can be done either clinically or using quantitative models and should place the patient in one of three categories: low probability (less than 5%), intermediate probability (5% to 65%), or high probability (greater than 65%). This is most useful when nodules are 8-30 mm. If the lesion is larger than 30 mm, the likelihood of malignancy is so high that it typically is resected; in contrast, when the lesion is smaller than 8 mm, the likelihood of malignancy is low and the patient should undergo routine radiological surveillance with serial CT scans.

Biopsy of the nodule or a transthoracic approach is preferred when the probability of malignancy is intermediate (5% to 65%) and would not be appropriate for this patient with a hypermetabolic nodule on PET/CT scan suggesting a high probability of malignancy. Furthermore, the sampling procedure is chosen according to size and location of the nodule, availability, and local expertise. Typically, peripheral nodules are sampled using CT-guided transthoracic needle aspiration, and more central lesions are sampled using bronchoscopic techniques. This lesion is described as peripheral.

Radiologic surveillance with serial CT scans is preferred if the probability of malignancy is low (less than 5%).

This patient's lung nodule is highly suspicious for malignancy on CT/PET scan so sampling with CT-guided transthoracic needle aspiration is not indicated.

Key Point

  • Patients with a solid indeterminate lung nodule larger than 8 mm and high probability of malignancy should be staged using a PET/CT scan followed by definitive management.