3D Specimen Mapping Expedites Frozen Section Diagnosis of Nonpalpable Ground Glass Opacities

BACKGROUND: Pulmonary ground glass opacities (GGOs) are early-stage adenocarcinoma spectrum lesions that are not easily palpable. Challenges in localizing GGOs during intraoperative pathology can lead to imprecise diagnoses and additional time under anesthesia. To improve localization of GGOs during frozen section diagnosis, we evaluated a novel technique, 3-dimensional near-infrared specimen mapping (3D-NSM).

METHODS: Fifty-five patients with a cT1 GGO were enrolled and received a fluorescent tracer preoperatively. After resection, specimens were inspected to identify lesions. Palpable and nonpalpable nodules underwent 3D-NSM and the area of highest fluorescence was marked with a suture. Time for 3D-NSM, time for frozen section diagnosis, and number of tissue sections examined were recorded. To compare 3D-NSM with standard-of-care techniques, a control cohort of 20 subjects with identical inclusion criteria were enrolled. Specimens did not undergo 3D-NSM and were sent directly to pathology.

RESULTS: 3D-NSM localized 54 of 55 lesions with 1 false negative. All 41 palpable lesions were identified by 3D-NSM. Thirteen (92.8%) of 14 nonpalpable lesions were located by 3D-NSM. Time to diagnosis for the 3D-NSM cohort was 23.5 minutes, compared with 26.0 minutes in the control cohort (P = .04). 3D-NSM did not affect time to diagnosis of palpable lesions (23.2 minutes vs 21.4 minutes; P = .10). 3D-NSM significantly reduced time to diagnosis for nonpalpable lesions (23.3 minutes vs 34.4 minutes; P < .0001). 3D-NSM also reduced the number of tissue sections analyzed in nonpalpable lesions (4.50 vs 11.00; P < .0001).

CONCLUSIONS: 3D-NSM accurately localizes GGOs and expedites intraoperative diagnosis by reducing the number of tissue sections analyzed for nonpalpable GGOs.