Education Icon

Non-Small Cell Lung Carcinoma with Neuroendocrine Features

Milos J Janicek, MD
Francine Jacobson, MD

March 5, 1996

Presentation

A 67-year-old black woman with a long smoking history presented with an incidental finding of a 2.5 cm nodule in the left upper lobe (LUL) on a previous chest radiograph. The metastatic work-up had been negative. She had undergone lingulectomy, sparing the left upper lobe, through video-thoracoscopy after negative mediastinoscopy.

Imaging Findings

Plain chest radiograph
Close-up of nodule on plain chest radiograph
CT of lung

Chest radiograph demonstrates a 1-cm, slightly lobulated, solitary, indeterminate lung nodule with suggestion of spiculated contour (arrow). [See the digitally enhanced close-up of the nodule from the radiograph (arrows).] This lesion is better demonstrated by computed tomography (CT) (arrow). No definite calcification is visible within the nodule.

Differential Diagnosis

Differential diagnosis includes primary (benign or malignant) tumor, secondary tumor, and granuloma; less likely are (fungus) pneumonia, hamartoma, arteriovenous malformation.

Diagnosis

Large cell neuroendocrine carcinoma

Discussion

After determination that a nodule seen on a radiograph is truly parenchymal (using fluoroscopy, oblique views, and CT), the most valuable indicator of the nature of that nodule is its growth pattern. Absence of growth for more than 2 years is considered the best noninvasive proof of benignity. The size criterion is no longer valid since Zerhouni et al (1) demonstrated that 42% of 177 malignant nodules measured less than 2 cm. In addition, while Spiegelman et al (2) suggested that CT density greater than 164 Hounsfield units (HU) indicated the benign nature of noncalcified pulmonary nodules, the finding was not corroborated by independent studies.

Strict criteria for determination of benign calcifications in lung nodules include (3):

Larger and more spiculated nodules are less likely to be benign, regardless of the presence or absence of calcifications.

On CT, the presence of fat is highly suggestive of hamartoma, especially in combination with calcifications. Very promising data presented by Swensen et al (4) suggest that maximum level of enhancement [after intravenous injection of 100mL (2nL/sec) nonionic contrast] for malignant lesions was never less than 20 HU as opposed to benign lesions with median enhancement at 12 HU.

Given the age and smoking history of our patient, the invasive approach and histological diagnosis outlined above were fully justified. However, development of minimally invasive thoracoscopic surgery will make possible more aggressive management of small pulmonary nodules in any patient.

References

1) Zerhouni ET et al. Computed tomography of the pulmonary nodule: A national cooperative study. Radiology 1986; 160:319-327.

2) Siegelman SS et al: CT of the solitary pulmonary nodule. AJR 1980; 135:1-13.

3) Caskey CI et al. Current evaluation of the solitary pulmonary nodule. Radiologic Clinics of North America 1990; 28:511-520.

4) Swensen SJ et al. CT evaluation of enhancement of pulmonary nodules with iodinated contrast material [abstract]. Radiology 1994; 193(P):233.

Dear Visitors: Nothing on this World Wide Web site should be considered medical advice. Only your own doctor can help you make decisions about your medical care. It is not the policy of the Brigham and Women's Hospital Department of Radiology to provide consultation on the World Wide Web or via e-mail. If you have a specific medical question or are seeking medical care, please call the Brigham and Women's Hospital toll-free physician referral line at 1-800-294-9999.

Is this a mirrored page?
The official homepage of the BrighamRAD Teaching Case Database is http://brighamrad.harvard.edu/education/online/tcd/tcd.html

Contact the BrighamRAD Design Team for additional information about this website.