The Different Evaluative Significance of Enlarged Lymph Nodes on Preoperative CT in the N Stage for Patients with Suspected Subsolid and Solid Lung Cancers.

RATIONALE AND OBJECTIVES

To investigate the clinical value of enlarged mediastinal and/or hilar lymph nodes on CT for patients with lung subsolid and solid nodules.

MATERIALS AND METHODS

The study was performed on patients who underwent surgical treatment for suspected lung cancer. One hundred seventeen subsolid nodules and 101 solid nodules with enlarged lymph nodes (LNs) were included in the study group. The same number of cases with normal LNs with a balanced distribution of the clinical T stage were randomly selected as the control group for each study group. The pathological statuses of the lymph nodes of these patients proven by histopathology after surgery were collected.

RESULTS

Lung solid lesions with enlarged LNs were more prone to lymph node metastasis (37.6% vs. 13.9%, p <0.001). However, there were only two and one metastatic lesions in the subsolid group with and without enlarged LNs, respectively. (2/117 vs. 1/117, p = 1.000). No pathological lymph node metastasis was observed in subsolid lesions under clinical stage T1b (cT1b), even though some of them (117/234) with enlarged LNs.

CONCLUSION

The evaluative significance of enlarged LNs on CT is different for subsolid and solid lesions. CT is useful for lymph node evaluation and N staging of solid lesions but may has little value for subsolid lesions. There is a very low possibility of lymph node metastasis occurring in patients with subsolid lesions under cT1b. Enlarged LNs on CT may not be critical in subsequent management and treatment for subsolid nodules.