Outcome of Incidental Pulmonary Nodules in a Real-World Setting

OBJECTIVES

Early diagnosis of lung cancer is imperative to improve survival. Incidental pulmonary nodules (IPN) may represent early stages of lung cancer and appropriate follow-up and management of these nodules is important, but also very resource demanding. We aim to describe the results of the CT-based follow-up on a cohort of patients with IPN in terms of detected malignancies, the proportion undergoing invasive procedures, and the subsequent outcome.

MATERIALS AND METHODS

Retrospective cohort study of patients in a CT IPN follow-up program who underwent a needle biopsy of the lung from 2018 to 2021 at Aarhus University Hospital.

RESULTS

A total of 4181 patients with IPN were followed with CT control scans. Out of these 249 (6%) were diagnosed with lung cancer of which 224 (90%) were diagnosed as a result of the IPN follow-up. Seventy-five percent of the patients were diagnosed in stages I to II and curable treatment was possible in 77.9% of the patients. In the CT IPN follow-up program 449 patients underwent a CT guided needle biopsy. Out of these 190 patients underwent biopsy without the detection of malignancy, corresponding to 4.5% of the entire IPN population.

CONCLUSION

The cumulated incidence of lung cancer in our population in the IPN follow-up program was 6%. The probability of malignancy when undergoing an invasive procedure on an IPN was 55.7% of which lung cancer was vastly predominant. The majority of lung cancers were diagnosed in an early and potentially curable stage.

Feasibility of tissue re-biopsy in non-small cell lung cancers resistant to previous epidermal growth factor receptor tyrosine kinase inhibitor therapies

Background

When epidermal growth factor receptor (EGFR) gene mutation-positive non-small cell lung cancer (NSCLC) acquires resistance to the initial tyrosine kinase inhibitor (TKI) treatment, reassessing the tumor DNA by re-biopsy is essential for further treatment selection. However, the process of TKI-sensitive tumor re-progression and whether re-biopsy is possible in all cases of acquired resistance to EGFR-TKI remain unclear.

Methods

We retrospectively analyzed data from 69 consecutive patients with EGFR gene mutation-positive advanced NSCLC who had been treated with EGFR-TKI and exhibited disease relapse after initial disease remission. The relapsing lesions were identified at the time of RECIST-progressive disease (PD) and clinical-PD (when the attending physician judged the patient as clinically relapsing and stopped EGFR-TKI therapy). We determined the potential re-biopsy methods for each relapsing lesion and evaluated their feasibility according to difficulty and invasiveness criteria as follows: category A, accessible by conventional biopsy techniques; category B, difficult (but possible) to biopsy and accessible with invasive methods; and category C, extremely difficult to biopsy or inaccessible without using highly invasive methods, including surgical biopsy.

Results

The total feasibility rate of re-biopsy (category A or B) was 68% at RECIST-PD and 84% at clinical-PD, and the most common accessible relapsing lesions were primary tumors at RECIST-PD and pleural effusion at clinical-PD. All relapsing lesions at primary sites (categories A and B) were assessed as having the potential for re-biopsy. However, re-biopsy for metastasis was assessed as difficult in a substantial proportion of the study population (42 and 20% category C at RECIST-PD and clinical-PD, respectively).

Conclusions

Re-biopsy of relapsing disease is feasible in many cases, although it may present difficulties in cases with, e.g., metastatic relapsing lesions. To facilitate treatment strategies in NSCLC patients with relapse after EGFR-TKI therapy, re-biopsy should be standardized with the use of simpler and more reliable methods.