Multifocal ground-glass opacities: multifocal origin versus intrapulmonary metastasis

Case report: Targeted sequencing facilitates the diagnosis and management of rare multifocal pure ground-glass opacities with intrapulmonary metastasis

Introduction

Treatments for multiple ground-glass opacities (GGOs) for which the detection rate is increasing are still controversial. Next-generation sequencing (NGS) may provide additional key evidence for differential diagnosis or optimal therapeutic schedules.

Case presentation

We first reported a rare case in which more than 100 bilateral pulmonary GGOs (91.7% of the GGOs were pure GGOs) were diagnosed as both multiple primary lung cancer and intrapulmonary metastasis. We performed NGS with an 808-gene panel to assess both somatic and germline alterations in tissues and plasma. The patient (male) underwent three successive surgeries and received osimertinib adjuvant therapy due to signs of metastasis and multiple EGFR-mutated tumors. The patient had multiple pure GGOs, and eight tumors of four pathological subtypes were evaluated for the clonal relationship. Metastasis, including pure GGOs and atypical adenomatous hyperplasia, was found between two pairs of tumors. Circulating tumor DNA (ctDNA) monitoring of disease status may impact clinical decision-making.

Conclusions

Surgery combined with targeted therapies remains a reasonable alternative strategy for treating patients with multifocal GGOs, and NGS is valuable for facilitating diagnostic workup and adjuvant therapy with targeted drugs through tissue and disease monitoring via ctDNA.

Utility of whole exome sequencing analysis in differentiating intrapulmonary metastatic multiple ground-glass nodules (GGNs) from multiple primary GGNs

Purpose

Clinical evidence of metastasis with ground-glass nodules (GGNs) has been reported, including pulmonary metastasis and distant metastasis. However, the clonal relationships of multiple GGNs at the genetic level remain unclear.

Experimental design

Sixty tissue specimens were obtained from 19 patients with multiple GGN lung cancer who underwent surgery in 2019. Whole exome sequencing (WES) was performed on tissue samples, and genomic profiling and clone evolution analysis were conducted to investigate the genetic characteristics and clonality of multiple GGNs.

Results

A total of 15,435 nonsynonymous mutations were identified by WES, and GGNs with shared nonsynonymous mutations were observed in seven patients. Copy number variant (CNV) analysis showed that GGNs in ten patients had at least one shared arm-level CNV. Mutational spectrum analysis showed that GGNs in three patients had similar six substitution profiles and GGNs in fou patients had similar 96 substitution profiles. According to the clone evolution analysis, we found that GGNs in five patients had shared clonal driver gene mutations. Taken together, we identified that 5 patients may have multiple primary GGNs without any similar genetic features, 2 patients may have intrapulmonary metastatic GGNs with ≥ 3 similar genetic features, and the other 12 patients cannot be determined due to insufficient evidences in our cohort.

Conclusions

Our findings suggest that the intrapulmonary metastasis exist in multiple GGNs, but the number of GGNs was not associated with the probability of metastasis. Application of genomic profiling may prove to be important to precise management of patients with multiple GGNs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10147-022-02134-8.

The Diagnosis of Intrapulmonary Metastasis Multifocal Pulmonary Ground-Glass Nodules Based on Oncogenic Driver Mutation: Two Case Reports and Review of Literature

With the increased use of low-dose computed tomography (LDCT), the detection of multifocal pulmonary ground-glass nodules (GGNs) has increased. According to the current clinical guidelines, multifocal GGNs tend to be treated as the multiple primary early-stage lung adenocarcinoma. However, studies have indicated that parts of multiple GGNs may originate from single nodules via intrapulmonary metastasis (IPM). Such IPM indicates the advanced stages even when the multiple GGNs are present as the early characteristics in pathological assessments. However, no gold standard exists for the differential diagnosis of multiple IPM GGNs. Here, we report two multifocal pulmonary GGNs cases where panel sequencing (672 driver mutation loci) showed that patient 1 (P1) shared two rare epidermal growth factor receptor (EGFR) mutations (primary L747_T751del and primary T790M) in the left upper lobe anterior segment and left lower lobe superior segment, respectively. Patient 2 (P2) shared a low-frequency human epidermal growth factor receptor 2 (HER2) mutation (primary Tyr772_Ala775dup) in two GGNs located in the apicoposterior and superior lingular segment of the left lower lobe (LLL). Oncogenic driver mutations were concordant between primary tumors and metastasis. Thus, shared low-frequency driver mutations in multiple GGNs strongly suggested that IPM existed with a high probability in these patients. Also, tumor cell spread through air spaces (STAS) was identified in pathological sections of the left upper lobe (LUL) nodule of P1, suggesting aerogenous spread may have been an effective pathway for IPM. Our report suggests that oncogenic driver mutations have prominent diagnostic value for IPM. Also, GGN IPM may occur in one lung lobe and between in different lung lobes.

The Impact of EGFR Tyrosine Kinase Inhibitor on the Natural Course of Concurrent Subsolid Nodules in Patients with Non-Small Cell Lung Cancer

Purpose

The role of epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR-TKIs) in the management of persistent subsolid nodules (SSNs) is unclear. This study aimed to investigate the impact of EGFR-TKIs on concurrent SSNs in patients with stage IV non–small cell lung cancer (NSCLC).

Materials and Methods

Patients who received an EGFR-TKI for at least 1 month for stage IV NSCLC and had concurrent SSN(s) that had existed for at least 3 months on chest computed tomography were included in this retrospective study. Size change of each nodule before and after EGFR-TKI therapies were evaluated using a cutoff value of 2 mm; increase (≥ 2 mm), decrease (≤ −2 mm), and no change (−2 mm < size change < +2 mm).

Results

A total of 77 SSNs, 51 pure ground-glass (66.2%) and 26 part-solid nodules (33.8%), were identified in 59 patients who received gefitinib (n=45) and erlotinib (n=14). Among 58 EGFR mutation analysis performed for primary lung cancer, 45 (77.6%) were EGFR mutant. The proportions of decrease group were 19.5% (15/77) on per-nodule basis and 25.4% (15/59) on per-patient basis. Four SSNs (5.2%) disappeared completely. On per-patient based multivariable analysis, EGFR exon 19 deletion positivity for primary lung cancer was associated with a decrease after initial EGFR-TKI therapy (adjusted odds ratio, 4.29; 95% confidence interval, 1.21 to 15.29; p=0.025).

Conclusion

Approximately 20% of the concurrent SSNs decreased after the initial EGFR-TKI therapy. EGFR exon 19 deletion positivity for primary lung cancer was significantly associated with the size change of concurrent SSNs.

Treatment options for pulmonary multifocal ground glass opacity type adenocarcinoma: Surgery combine thermal ablation?

Objectives

To retrospectively analyze the clinical results of the treatment of pulmonary multifocal adenocarcinoma presenting as ground glass opacity (GGO) by surgery and thermal ablation.

Methods

87 GGO-type pulmonary adenocarcinomas of 48 patients (14 males and 34 females; mean age: 59.7 years old ±9.9, range: 33–79 years old) had been treated from March 2015 to March 2019. Treatment means included 43 wedge resections, 7 segmentectomy, 17 lobectomies, and 20 thermal ablations. The indication selected for treatment means, safety, and local tumor progression rate were evaluated.

Results

No operation-related death occurred in all patients. 42 times of surgery were performed and 67 carcinomas were resected in 42 patients. 23 times of single-port Video-assisted thoracoscopic surgery (VATS), 8 times of two-port VATS and 11 times of three-port VATS were performed in total. There were 2 cases of air leak (exceeding 1 week), 1 case of chylothorax and 1 case of massive pleural effusion. Time duration of surgery was between 60 and 300mins (mean: 167mins). Intra-operative blood loss was between 5 and 300 ​mL (mean: 44 ​mL). Time of chest drainage was between 2 and 23d (mean 4.9d). Chest drainage volume was between 14 and 4633 ​mL (mean: 872 ​mL). Post-operation LOS (length of stay) was between 3 and 25d (mean: 6.2d). 15 times of thermal ablation were performed (1 case of air leak) and 20 carcinomas were ablated in 14 patients. The ablation time was between 30 and 120min (mean: 43min); post-operation LOS was between 1 and 10d (mean: 3.5d). During the mean follow-up period (16 months ​± ​13) (range: 5–60 months), no local tumor progression occurred.

Conclusions

Surgery and thermal ablation are safe and effective options for the treatment of pulmonary multifocal GGO-type adenocarcinoma.

[Diagnosis and Treatment of Pulmonary Multifocal Ground-glass Nodules]

In recent years, with the development of the high resolution computed tomography (HRCT) screening program for lung cancer, the multifocal ground-glass nodule (GGN) has been discovered more and more. Because there are still many uncertainties in the diagnosis and treatment of multifocal GGN in lung, this paper reviews the clinical concerns such as the follow-up interval and time, the relationship between main focus and other focuses, diagnosis, treatment and follow-up of residual nodules.