Use of CT-derived radiomic features to preoperatively identify invasive mucinous adenocarcinoma in solitary pulmonary nodules ≤3 cm

Objective

In this study, we aimed to utilize computed tomography (CT)-derived radiomics and various machine learning approaches to differentiate between invasive mucinous adenocarcinoma (IMA) and invasive non-mucinous adenocarcinoma (INMA) preoperatively in solitary pulmonary nodules (SPN) ≤3 cm.

Methods

A total of 538 patients with SPNs measuring ≤3 cm were enrolled, categorized into either the IMA group (n = 50) or INMA group (n = 488) based on postoperative pathology. Radiomic features were extracted from non-contrast-enhanced CT scans and identified using the least absolute shrinkage and selection operator (LASSO) algorithm. In constructing radiomics-based models, logistic regression, support vector machines, classification and regression trees, and k-nearest neighbors were employed. Additionally, a clinical model was developed, focusing on CT radiological features. Subsequently, this clinical model was integrated with the most effective radiomic model to create a combined model. Performance assessments of these models were conducted, utilizing metrics such as the area under the receiver operating characteristic curve (AUC), DeLong's test, net reclassification index (NRI), and integrated discrimination improvement (IDI).

Results

The support vector machine approach showed superior predictive efficiency, with AUCs of 0.829 and 0.846 in the training and test cohorts, respectively. The clinical model had AUCs of 0.760 and 0.777 in the corresponding cohorts. The combined model had AUCs of 0.847 and 0.857 in the corresponding cohorts. Furthermore, compared to the radiomic model, the combined model significantly improved performance in both the training (DeLong test P = 0.045, NRI 0.206, IDI 0.024) and test cohorts (P = 0.029, NRI 0.125, IDI 0.032), as well as compared to the clinical model in both the training (P = 0.01, NRI 0.310, IDI 0.09) and test cohorts (P = 0.047, NRI 0.382, IDI 0.085).

Conclusion

the combined model exhibited excellent performance in distinguishing between IMA and INMA in SPNs ≤3 cm.

Favorable treatment response of bevacizumab-combined chemotherapy for advanced or recurrent invasive mucinous adenocarcinoma of the lung: A retrospective observational study

Invasive mucinous adenocarcinoma (IMA) of the lung is a rare variant of adenocarcinoma characterized by abundant intracytoplasmic mucin within the tumor. Although IMA has poor sensitivity to conventional chemotherapy regimens used for non-small cell lung cancer, we observed a better response to the bevacizumab (BEV) regimen. In this retrospective study, we aimed to investigate the response to BEV-combined regimens in patients with IMA. Among 16 consecutive patients diagnosed with IMA between January 2016 and December 2020 at our institution and treated with systemic chemotherapy, seven patients were treated with BEV-combined regimens. The overall response rate to BEV-combined regimens was 85.7%, with six patients showing a partial response. The median progression-free survival was 6.1 months. One patient experienced respiratory failure, which was improved after administration of BEV-combined regimen. BEV-combined systemic therapy may have a favorable effect on advanced or recurrent IMA of the lung.

Mixed invasive mucinous and non-mucinous adenocarcinoma of the lung with hematogenous metastases to multiple organs

Mixed invasive mucinous and non-mucinous adenocarcinoma is a rare variant of lung adenocarcinoma. In pure invasive mucinous adenocarcinoma, multilobar and bilateral involvement are common, and extrathoracic metastasis is rare. Here, we report a case of mixed invasive mucinous and non-mucinous adenocarcinoma with distant metastasis to multiple organs without marked enlargement of the primary lung lesion. The pathological findings indicated high tumor invasiveness and the patient died 10 months after diagnosis despite chemoimmunotherapy. Further investigations are necessary to elucidate the clinical characteristics and appropriate management of mixed invasive mucinous and non-mucinous adenocarcinoma.

Establishment and characterization of novel high mucus-producing lung tumoroids derived from a patient with pulmonary solid adenocarcinoma

Among mucus-producing lung cancers, invasive mucinous adenocarcinoma of the lung is a rare and unique subtype of pulmonary adenocarcinoma. Notably, mucus production may also be observed in the five subtypes of adenocarcinoma grouped under the higher-level diagnosis of Invasive Non-mucinous Adenocarcinomas (NMA). Overlapping pathologic features in mucus-producing tumors can cause diagnostic confusion with significant clinical consequences. In this study, we established lung tumoroids, PDT-LUAD#99, from a patient with NMA and mucus production. The tumoroids were derived from the malignant pleural effusion of a patient with lung cancer and have been successfully developed for long-term culture (> 11 months). Karyotyping by fluorescence in situ hybridization using an alpha-satellite probe showed that tumoroids harbored aneuploid karyotypes. Subcutaneous inoculation of PDT-LUAD#99 lung tumoroids into immunodeficient mice resulted in tumor formation, suggesting that the tumoroids were derived from cancer. Xenografts from PDT-LUAD#99 lung tumoroids reproduced the solid adenocarcinoma with mucin production that was observed in the patient's metastatic lymph nodes. Immunoblot analysis showed MUC5AC secretion into the culture supernatant of PDT-LUAD#99 lung tumoroids, which in contradistinction was barely detected in the culture supernatants of NCI-A549 and NCI-H2122 pulmonary adenocarcinoma cells known for their mucin-producing abilities. Here, we established a novel high-mucus-producing lung tumoroids from a solid adenocarcinoma. This preclinical model may be useful for elucidating the pathogenesis of mucus-producing lung cancer.

[Construction of a Prognostic Prediction Model of Patients with Pathologic N0 in Resected Invasive Mucinous Adenocarcinoma of the Lung]

BACKGROUND

Invasive mucinous adenocarcinoma (IMA) was a rare and specific type of lung adenocarcinoma, which was often characterized by fewer lymphatic metastases. Therefore, it was difficult to evaluate the prognosis of these tumors based on the existing tumor-node-metastasis (TNM) staging. So, this study aimed to develop Nomograms to predict outcomes of patients with pathologic N0 in resected IMA.

METHODS

According to the inclusion criteria and exclusion criteria, IMA patients with pathologic N0 in The Affiliated Lihuili Hospital of Ningbo University (training cohort, n=78) and Ningbo No.2 Hospital (validation cohort, n=66) were reviewed between July 2012 and May 2017. The prognostic value of the clinicopathological features in the training cohort was analyzed and prognostic prediction models were established, and the performances of models were evaluated. Finally, the validation cohort data was put in for external validation.

RESULTS

Univariate analysis showed that pneumonic type, larger tumor size, mixed mucinous/non-mucinous component, and higher overall stage were significant influence factors of 5-year progression-free survival (PFS) and overall survival (OS). Multivariate analysis further indicated that type of imaging, tumor size, mucinous component were the independent prognostic factors for poor 5-year PFS and OS. Moreover, the 5-year PFS and OS rates were 62.82% and 75.64%, respectively. In subgroups, the survival analysis also showed that the pneumonic type and mixed mucinous/non-mucinous patients had significantly poorer 5-year PFS and OS compared with solitary type and pure mucinous patients, respectively. The C-index of Nomograms with 5-year PFS and OS were 0.815 (95%CI: 0.741-0.889) and 0.767 (95%CI: 0.669-0.865). The calibration curve and decision curve analysis (DCA) of both models showed good predictive performances in both cohorts.

CONCLUSIONS

The Nomograms based on clinicopathological characteristics in a certain extent, can be used as an effective prognostic tool for patients with pathologic N0 after IMA resection.

Invasive mucinous adenocarcinoma of the lung with bronchorrhea - A marked reduction volume of sputum after SARS-CoV-2 infection

Bronchorrhea is a watery sputum volume of at least 100 mL/day, which is commonly associated with lung malignancies. We report a 57-year-old woman was admitted to the hospital with a cough, profuse sputum. Chest CTs showed crazy paving pattern and lung nodules. Cell nests were visible on the Thinprep Cytologic Test. The case was considered an invasive mucinous adenocarcinoma of the lung combined with bronchorrhea. Significantly, the sputum volume declined rapidly and did not rise again when the patient was diagnosed with COVID-19 and treated with nirmatrelvir/ritonavir. This case is suggestive of studies related to regulatory mediators associated with bronchorrhea.

Distinct Recurrence Pattern and Survival Outcomes of Invasive Mucinous Adenocarcinoma of the Lung: The Potential Role of Local Therapy in Intrapulmonary Spread

BACKGROUND

Invasive mucinous adenocarcinoma (IMA) is distinct from non-mucinous adenocarcinoma, but studies on recurrent IMA are scarce. Thus, this study aimed to evaluate the recurrence patterns of IMA and the role of pulmonary local therapy (LT) in resectable pulmonary recurrence of IMA.

METHODS

The study reviewed 403 patients with surgically resected IMA between 1998 and 2018. The recurrence patterns were categorized as solitary pulmonary recurrence (SPR), multiple pulmonary recurrence (MPR), and extra-pulmonary recurrence (EPR). The clinicopathologic characteristics, overall survival (OS), and post-recurrence survival (PRS) were analyzed according to the recurrence pattern and LT administration.

RESULTS

Recurrences were found in 91 (22.6%) patients, including 18 patients with SPR, 37 patients with MPR, and 36 patients with EPR. Compared with the MPR and EPR groups, the SPR group had a longer disease-free interval (32.5 vs. 9.6 vs. 10.1 months, respectively; p < 0.01) and a better OS (5-year OS: 88.5%, 41.5%, and 22.9%, respectively; p < 0.01). In case of resectable pulmonary recurrence, pulmonary LT was administered to 15 patients with SPR and 3 patients with MPR. These patients showed a better 5-year PRS than the other patients with pulmonary recurrence (86.3% vs. 30.4%; p < 0.01). Notably, long-term survival was observed for one patient with MPR undergoing LT and two patients with SPR undergoing a second LT for a second pulmonary recurrence.

CONCLUSIONS

In this series, the patients with recurrent IMA showed different prognoses according to the recurrence pattern. The patients with pulmonary recurrence of IMA undergoing LT showed a favorable prognosis, suggesting the potential role of LT for resectable pulmonary recurrence of IMA.

Comparison of the immunotherapy efficacy between invasive mucinous and non-mucinous adenocarcinoma in advanced lung cancer patients with KRAS mutation: a retrospective study

Invasive mucinous adenocarcinoma (IMA) is a rare variant of adenocarcinoma with unique clinical, radiological, and pathological features, among which KRAS mutation is the most common. However, the differences in the efficacy of immunotherapy between KRAS-positive IMA and invasive non-mucinous adenocarcinoma (INMA) patients remain unclear. Patients with KRAS mutated adenocarcinomas receiving immunotherapy between June 2016 and December 2022 were enrolled. Based on mucin-producing status, the patients were placed into two subgroups: the IMA group and INMA group. Patients with IMA were further classified into two subtypes according to the presence of mucin patterns: pure IMA (≥ 90%) and mixed mucinous/nonmucinous adenocarcinoma (≥ 10% of each histological component). Kaplan-Meier Curves and log-rank tests were used to analyze survival. Cox regression analysis of PFS were used to analyze the independent factors associated with efficacy. Sixty-five advanced adenocarcinoma patients with KRAS mutations received immunotherapy, including 24 patients with IMA and 41 with INMA. The median progression-free survival (PFS) was 7.7 months, whereas the median overall survival (OS) was 24.0 months. Significant difference in PFS could be observed in IMA and INMA (3.5 months vs. 8.9 months; P = 0.047). Patients with pure IMA tended toward prolonger survival in contrast to mixed mucinous/nonmucinous adenocarcinoma in PFS (8.4 months vs. 2.3 months; P = 0.349). The multivariable analysis demonstrated that IMA was an independent risk factor for PFS. In KRAS mutated patients, IMA was associated with poorer PFS after immunotherapy compared with INMA.

A Case of Invasive Mucinous Adenocarcinoma with Acute Respiratory Distress Syndrome Diagnosed by Autopsy Findings

We herein report a fatal case of invasive mucinous adenocarcinoma (IMA) with acute respiratory distress syndrome (ARDS) diagnosed based on autopsy findings. A 76-year-old man presented with severe respiratory discomfort on admission. Computed tomography (CT) revealed a peripheral distribution of consolidation. Although his respiratory status improved after steroid therapy, re-exacerbation occurred, and the patient died on day 131. A bronchoscopic lung biopsy had shown organizing pneumonia, but a post-mortem examination surprisingly revealed IMA with organizing pneumonia. IMA presenting with ARDS as the first symptom is extremely rare.

Primary lung invasive adenocarcinoma misdiagnosed as infectious pneumonia in 18F-FDG PET/CT:A case report

A 64-year-old woman presented to our hospital with cough and a large amount of white foam sputum, F-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) showed diffuse ground-glass opacities in both lungs, which was considered as infectious pneumonia. However, after ineffective anti-infection, the primary invasive mucinous adenocarcinoma was finally diagnosed. Pulmonary invasive mucinous adenocarcinoma is rare and special subtype of lung adenocarcinoma, it has a variety of imaging manifestations. When intense tracer uptake, air bronchial sign, honeycomb sign present in diffuse ground-glass opacities in F-FDG PET/CT, lung invasive mucinous adenocarcinoma should be highly suspected.

Invasive Mucinous Adenocarcinomas With Spatially Separate Lung Lesions: Analysis of Clonal Relationship by Comparative Molecular Profiling

INTRODUCTION

Pulmonary invasive mucinous adenocarcinomas (IMAs) often present with spatially separate lung lesions. Clonal relationship between such lesions, particularly those involving contralateral lobes, is not well established. Here, we used comparative genomic profiling to address this question.

METHODS

Patients with genomic analysis performed on two IMAs located in different lung regions were identified. Molecular assays included DNA-based next-generation sequencing (NGS) for 410 to 468 genes (Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets), RNA-based NGS for 62 genes (Memorial Sloan Kettering-Fusion), or non-NGS assays.

RESULTS

Comparative genomic profiling was performed on two separate IMAs in 24 patients, of whom 19 had contralateral lesions. Tumors from all but one patient shared matching driver alterations, including KRAS (n = 19), NRG1 (n = 2), ERBB2 (n = 1) or BRAF (n = 1). In addition, in patients with paired tumors profiled by NGS (n = 12), shared driver alterations were accompanied by up to 4 (average 2.6) other identical mutations, further supporting the clonal relationship between the tumors. Only in a single patient separate IMAs harbored entirely nonoverlapping mutation profiles, supporting clonally unrelated, distinct primary tumors. Notably, in a subset of patients (n = 3), molecular testing confirmed a clonal relationship between the original resected IMAs and subsequent contralateral IMA presenting after an extremely long latency (8.1-11.7 y).

CONCLUSIONS

Comparative molecular profiling supports that nearly all separate pulmonary IMA lesions represent intrapulmonary spread arising from a single tumor and documents a subset with a remarkably protracted course of intrapulmonary progression. This study reinforces the unique biology and clinical behavior of IMAs while further highlighting the value of genomic testing for clarifying the clonal relationship between multiple lung carcinomas.

A case of bilateral invasive mucinous adenocarcinoma of the lung with severe productive cough and dyspnea successfully treated with palliative lung lobectomy

Invasive mucinous adenocarcinoma (IMA) of the lung is a chemo-refractory type of lung cancer with frequent intrapulmonary dissemination. Patients with IMA of the lung often suffer from a productive cough and rapid deterioration of performance status (PS). There is currently no standard therapeutic strategy against this unrelenting condition. Here we report a patient with bilateral IMA of the lung with severe productive cough and dyspnea successfully controlled by palliative lung lobectomy. A 67-year-old Japanese man presented with a 3-month history of productive cough. Chest computed tomography (CT) revealed a mass lesion in the left lower lobe and a small nodule and multiple thin-walled cystic lesions in the right lung. He was diagnosed with stage IIB IMA of the lung. Over the next two weeks, his productive cough and dyspnea drastically worsened and his PS declined from 0 to 4. Chest CT showed increases in size of both the nodule and cystic lesions in the right lung and the mass lesion in the left lower lobe. He was re-diagnosed as stage IVA. Given the extreme heterogeneity of the tumor distribution, we decided to perform palliative resection of the left lower lobe. After the surgery, he experienced complete relief of respiratory symptoms, and his PS improved dramatically, enabling chemotherapy. Thirty-one months after surgery, he maintains good PS. In conclusion, our report suggests that aggressive introduction of palliative lung lobectomy played a substantial role for in the excellent outcome of our patient with relatively well confined, advanced-stage IMA.

Primary Invasive Mucinous Adenocarcinoma of the Lung: Prognostic Value of CT Imaging Features Combined with Clinical Factors

Objective

To investigate the association between CT imaging features and survival outcomes in patients with primary invasive mucinous adenocarcinoma (IMA).

Materials and Methods

Preoperative CT image findings were consecutively evaluated in 317 patients with resected IMA from January 2011 to December 2015. The association between CT features and long-term survival were assessed by univariate analysis. The independent prognostic factors were identified by the multivariate Cox regression analyses. The survival comparison of IMA patients was investigated using the Kaplan-Meier method and propensity scores. Furthermore, the prognostic impact of CT features was assessed based on different imaging subtypes, and the results were adjusted using the Bonferroni method.

Results

The median follow-up time was 52.8 months; the 5-year disease-free survival (DFS) and overall survival rates of resected IMAs were 68.5% and 77.6%, respectively. The univariate analyses of all IMA patients demonstrated that 15 CT imaging features, in addition to the clinicopathologic characteristics, significantly correlated with the recurrence or death of IMA patients. The multivariable analysis revealed that five of them, including imaging subtype (p = 0.002), spiculation (p < 0.001), tumor density (p = 0.008), air bronchogram (p < 0.001), emphysema (p < 0.001), and location (p = 0.029) were independent prognostic factors. The subgroup analysis demonstrated that pneumonic-type IMA had a significantly worse prognosis than solitary-type IMA. Moreover, for solitary-type IMAs, the most independent CT imaging biomarkers were air bronchogram and emphysema with an adjusted p value less than 0.05; for pneumonic-type IMA, the tumors with mixed consolidation and ground-glass opacity were associated with a longer DFS (adjusted p = 0.012).

Conclusion

CT imaging features characteristic of IMA may provide prognostic information and individual risk assessment in addition to the recognized clinical predictors.

Prognostic Impact of Histopathologic Features in Pulmonary Invasive Mucinous Adenocarcinomas

OBJECTIVES

The prognostic significance of pathologic features and invasive size has not been well studied for invasive mucinous adenocarcinoma (IMA). This study evaluates the significance of pathologic features and invasive size in relation to clinical outcome.

METHODS

We reviewed the pathologic features in 84 IMAs, including histologic pattern, nuclear atypia, mitosis, necrosis, and lymphovascular invasion. The invasive size was calculated from the total size using the percentage of invasive components. Cases were subdivided into two pathologic grades based on five pathologic features, and the pathologic grade and adjusted T (aT) stage were correlated with disease-free and overall survival (OS).

RESULTS

Necrosis and N stage were significantly associated with aT stage, and a significant association was noted between OS and aT stage. Nuclear atypia, mitosis, and lymphovascular and pleural invasion also showed a significant association with OS. High-grade tumors showing a significantly worse OS compared with low-grade tumors, as well as pathologic grade (hazard ratio [HR], 2.337; P = .043) and aT stage (HR, 1.875; P = .003), were independent prognostic factors in multivariate analysis.

CONCLUSIONS

The pathologic grading system stratified IMAs into high- and low-grade tumors with significant differences in OS. Invasive size may provide a better prognostic stratification for OS.

Prognostic impact of mucin spread, tumor cell spread, and invasive size in invasive mucinous adenocarcinoma of the lung

OBJECTIVES

The pathological T descriptor of lung invasive mucinous adenocarcinoma (IMA) is currently defined according to mucin spread, whereas that of lung non-mucinous adenocarcinoma is defined according to invasive lesion. This study aimed to evaluate and compare the prognostic impact of mucin spread, tumor cell spread, and invasive lesion in patients with lung IMA.

MATERIALS AND METHODS

Twenty-seven patients with completely resected pT1-4N0M0 IMA were evaluated. The radiological size (RS), mucin spread size (MS), tumor cell spread size (TS), and invasive size (IS) of the primary tumors were determined. Cox proportional hazards models were used to estimate recurrence-free survival (RFS). Because the MS, TS, and IS may be mutually confounding factors, they were evaluated using separate multivariate models including potential prognostic factors identified as significant on univariate analyses.

RESULTS

The median postoperative follow-up time was 4.9 years. TS and IS were significantly smaller than RS by a median of 0.3 cm (p = 0.027) and 1.4 cm (p < 0.0001), whereas MS and RS were not significantly different (p > 0.999). Univariate analyses identified T descriptors defined by MS, TS, and IS as potentially negative prognostic factors, in addition to age >75 years and carcinoembryonic antigen >5 ng/mL. Multivariate analyses revealed that T factors defined by MS, TS, and IS were significant predictors of RFS (p < 0.0001, p = 0.0002, and p = 0.0067, respectively).

CONCLUSION

MS is a reasonable determinant of the pathological T descriptor of lung IMA. TS and IS are potential candidates, although they remain discordant with RS. If the TS or IS is to be considered a candidate for the pathological T descriptor of lung IMA, the discordance with RS should first be resolved. If IS is used to define pathological T factor, clear criteria for mucinous AIS/MIA with IMA features should be developed.

Optimal method for measuring invasive size that predicts survival in invasive mucinous adenocarcinoma of the lung

PURPOSE

The purpose of this study was to determine the optimal method for measuring pathological invasive size that predicts prognosis in invasive mucinous adenocarcinoma (IMA).

METHODS

We analyzed patients who underwent complete surgical resection for lung IMA. The invasive size of IMA was measured using two methods: (1) excluding lepidic method (ELM), that is, lepidic component was excluded from the invasive area regardless of alveolar mucin and (2) including lepidic method (ILM), that is, lepidic component was included as invasive area if alveolar space was filled with mucin. The prognostic predictability of ELM and ILM on survival was assessed using univariable and multivariable Cox regression models. The discriminative power was assessed using concordance probability estimate (CPE) and Akaike's information criteria (AIC), and the prognostic impact of the newly redefined pathological stage according to ELM or ILM was also assessed.

RESULTS

A total of 101 patients were included. The median invasive size via ELM and ILM was 1.4 cm (range, 0.0-7.7 cm) and 2.1 cm (range, 0.0-14.2 cm), respectively. ELM had better discriminative power than ILM (ELM, HR = 1.38, AIC = 110.19, CPE = 0.671; ILM, HR = 1.19, AIC = 111.52, CPE = 0.655). Although the survival curves based on ILM crossed between T3 and T4, the overall survival (OS) curves based on ELM were sufficiently distinct from one another.

CONCLUSIONS

ELM has higher discriminative power for OS, and thus the optimal method for measuring the pathological invasive size of IMA should exclude the lepidic component regardless of alveolar mucin.

[Advanced Pneumonic-type Lung Carcinoma: A Retrospective Study of Clinical-radiological-pathological Characteristics with Survival Analysis in A Single Chinese Hospital]

背景与目的

肺炎型肺癌是一种临床和影像表现特殊的肺癌。本研究旨在总结此类肺癌的临床、影像及病理学特征，诊断手段，治疗方案及预后情况。

方法

肺炎型肺癌定义为：肺部计算机断层扫描（computed tomography, CT）以磨玻璃或实变影为主要表现，经组织学或细胞学明确诊断的肺癌。收集2013年1月1日-2018年8月30日期间，就诊于北京协和医院呼吸与危重症医学科的晚期肺炎型肺癌病例，回顾性分析这些患者临床资料并进行生存随访。

结果

共纳入46例患者，均为肺腺癌。咳嗽（41/46, 89.1%）、咳痰（35/46, 76.1%）是最常见的临床表现。胸部CT常见表现为磨玻璃影（87.0%）、实变影（84.8%）、以及多发磨玻璃结节（84.8%），多发囊样变和空洞分别为40.0%和13.0%。同侧及对侧肺转移分别见于95.3%和84.8%的病例。从出现症状到明确诊断的中位时间为214天（95%CI: 129-298）。CT引导肺穿刺活检及外科肺活检的确诊率为100%，支气管镜下的支气管肺泡灌洗（BAL）联合经支气管肺活检（TBLB）的确诊率为80.9%（17/21），痰液病理学检查的确诊率为45.0%（9/20）。病理亚型，26例（26/46, 56.5%）为浸润性粘液腺癌，20例患者因缺乏足够的病理标本量而无法进一步区分亚型。38例进行了EGFR基因检测，6例（6/38, 15.8%）有突变。33例进行ALK基因检测，仅1例（1/33, 3.0%）有ALK重排。中位总生存期（overall survival, OS）为522天（95%CI: 424-619）。EGFR野生型或ALK融合基因阴性的患者，化疗明显延长中位OS（HR=0.155, P=0.002, 2），接受化疗者中位OS 547天（95%CI: 492-602），不接受化疗者中位OS 331天（95%CI: 22-919）。

结论

肺炎型肺癌由于其临床和影像特征与肺部感染相似而经常导致延误诊断。支气管镜下的BAL联合TBLB有相当高的确诊率。浸润性粘液腺癌为肺炎型肺癌的主要病理亚型。肺炎型肺癌EGFR突变及ALK重排发生率很低。对于无明确驱动基因的患者，应积极行化疗，延长患者生存期。

Next generation sequencing of lung adenocarcinoma subtypes with intestinal differentiation reveals distinct molecular signatures associated with histomorphology and therapeutic options

OBJECTIVES

We aim to provide a better understanding of the molecular landscape of primary lung adenocarcinomas with intestinal differentiation.

MATERIAL AND METHODS

Five invasive mucinous adenocarcinomas (IMA) and seven pulmonary enteric adenocarcinomas (PEAD) were included in this study. Furthermore, we analyzed six pulmonary colloid adenocarcinomas (CAD), including one primary tumor, one metastasis, and two sample pairs consisting of the primary colloid lung tumor and a matching metastasis and an acinar component, respectively. All samples were characterized using immunohistochemistry (TTF-1, CK7, CK20, CDX2, Ki-67, ALK and PD-L1) and a next generation sequencing panel covering 404 cancer-related genes (FoundationOne® gene panel).

RESULTS AND CONCLUSION

While Ki-67 expression was comparably low in IMA (range: 8-15%) and in primary CAD (range: 5-8%), we observed considerably higher proliferation rates in the non-colloid tumor compartment (16%) and metastases (72%) from CAD, as well as in the PEAD-group (36-71%). The overall tumor mutational burden was lowest in IMA (2.5 mutations per megabase), intermediate in CAD (5.8 mutations per megabase) and highest in PEAD (16.8 mutations per megabase). KRAS mutations were frequent in all three tumor subtypes, but TP53 mutations were mostly limited to PEAD. While chromosomal alterations were rare in IMA, we discovered MYC amplifications in three of four CAD. Comparing primary and metastatic CAD, we observed the acquisition of multiple mutations and chromosomal alterations. PEAD had a variety of chromosomal alterations, including two cases with RICTOR amplification. PD-L1 expression (20%, 50% and 80% of tumor cells) was limited to three PEAD samples, only. In conclusion, we provide a detailed insight into the molecular alterations across and within the different subtypes of pulmonary adenocarcinomas with intestinal differentiation. From a clinical perspective, we provide data on potential treatment strategies for patients with PEAD, including immunotherapy.

Comparing clinicopathological features and prognosis of primary pulmonary invasive mucinous adenocarcinoma based on computed tomography findings

Objective

To evaluate the relationship between clinicopathologic characteristics and prognosis in patients with invasive mucinous adenocarcinoma (IMA) of the lung.

Methods

A total of 68 patients who underwent surgical resection for primary lung IMA were reviewed during the period of 2009 and 2017. Tumors were classified as solitary-type or pneumonic-type according to the computed tomography (CT) findings. Cox proportional hazards model was used to assess the effects of clinicopathological characteristics on univariate and multivariable analyses of disease-free survival (DFS).

Results

Solitary-type was found in 54 patients, while pneumonic-type was found in 14 patients. The patients’ age varied between 56 and 68 years (patients’ median age was 61 years). Besides, 50 patients had T1/T2 tumor stage (73.5%). Compared with solitary-type, higher T stage, N stage, and pathological stage (P < 0.001) were found in pneumonic-type. Moreover, the survival analysis showed that the pneumonic-type had a significantly poorer DFS compared with solitary-type (P = 0.004). Univariate analysis showed that pneumonic pattern on CT scan, T stage, pathologic stage, and thyroid transcription factor-1 (TTF-1) were significant predictive factors of survival (P = 0.011, 0.014, 0.013, 0.029, respectively). Multivariate analysis further indicated that pneumonic-type was the only independent prognostic factor for poor survival [hazard ratio (HR) = 6.764, 95% confidence interval (CI): 1.563–29.269, P = 0.011].

Conclusions

Based on CT findings, the solitary-type IMA is associated with a lower stage and better prognosis compared with the pneumonic-type IMA.

Molecular characteristics of multifocal invasive mucinous adenocarcinoma of the lung: Report of a rare case

Invasive mucinous adenocarcinoma (IMA) is an uncommon entity in the lung, with a poor prognosis. Multifocal IMA of the lung is even more unusual, and there is little experience with effective treatments. Herein, we present a case of multifocal IMA diagnosed in a 36 year‐old man by video‐assisted thoracoscopic surgery. A right middle lobe and a nodule in the right upper lobe were resected, as were mediastinal lymph nodes, leaving behind an autonomous right lower lobe nodule. To explore the feasibility of molecular treatment, next‐generation sequencing of genetic mutations was performed after four cycles of chemotherapy (pemetrexed + cisplatin). Ultimately, a KIAA1468‐RET fusion gene was detected at a disproportionate level (~67.3%), indicating that targeted therapy may be efficacious in treating this disease.

Lepidic predominant adenocarcinoma and invasive mucinous adenocarcinoma of the lung exhibit specific mucin expression in relation with oncogenic drivers

OBJECTIVES

To evaluate MUC1, MUC2, MUC5B, MUC5AC, and MUC6 expression in invasive lepidic predominant adenocarcinoma (LPA) and invasive mucinous adenocarcinoma (IMA) of the lung, and the impact of oncogenic drivers.

MATERIALS AND METHODS

MUC1, MUC2, MUC5B, MUC5AC, MUC6, TTF1 and Hnf4α immunohistochemistry was performed on surgical samples from 52 patients with IMA (n=25) or LPA (n=27). We searched for EGFR, KRAS, BRAF, and HER2 mutations and ALK, ROS1, and NRG1 rearrangements.

RESULTS

MUC1, MUC2, MUC5B, MUC5AC, and MUC6 expression was detected in tumor cells in 77%, 2%, 63%, 36%, and 21% of cases, respectively. MUC1 was significantly more overexpressed in LPA. MUC5B, MUC5AC, and MUC6 were typically detected in goblet cells and overexpressed in IMA. Hnf4α-positive IMA (n=11) were TTF1-negative and typically did not expressed MUC1 and expressed MUC5AC and MUC6. Hnf4α-negative IMA (n=14) showed a reverse profile of mucins expression, with MUC1 expression and a lack of MUC5AC and MUC6 expression. EGFR-positive status was significantly associated with LPA, MUC1 expression, and no MUC5B, MUC5AC, or MUC6 expression. KRAS-positive status was significantly associated with IMA and MUC5B and MUC5AC expression.

CONCLUSIONS

LPA and IMA exhibit specific mucin expression profiles, with MUC1 being associated with LPA, while MUC5B, MUC5AC, and MUC6 were associated with IMA. Hnf4α expression and EGFR and KRAS mutations may play a role in mucin expression profiles of these lung adenocarcinoma subtypes.

Non-Mucinous Lepidic Predominant Adenocarcinoma Presenting with Extensive Aerogenous Spread

An extremely rare case of non-mucinous lepidic-predominant invasive adenocarcinoma (LPA) showing extensive aerogenous spread with a pneumonic presentation is reported. A 73-year-old woman was referred to our hospital because of an infiltrative shadow on chest xray. Chest computed tomography revealed extensive ground glass opacities in the right lower lobe, which was accompanied by infiltrative shadow with a pneumonic presentation. Invasive mucinous adenocarcinoma was presumed, and a partial resection of the right lower lobe was done. Histopathological examination revealed lepidic growth-predominant invasive adenocarcinoma with Clara type tumor cells, and there were innumerable aerogenous metastases also consisting of Clara cells. Because Alcian Blue and periodic acid-Schiff staining disclosed no mucus, the tumor was diagnosed as a non-mucinous LPA. The patient showed a poor response to 5 courses of pemetrexed, and she died one year after the diagnosis due to cancer progression. Nonmucinous LPA showed a rare presentation characterized by extensive aerogenous spread followed by a poor prognosis.

Analysis of the clinicopathologic characteristics and prognostic of stage I invasive mucinous adenocarcinoma

PURPOSE

The correlations between histological, clinical features and prognosis of stage I invasive mucinous adenocarcinoma (IMA) have not been thoroughly studied for its rare incidence. This study aimed to compare the prognosis among IMA with different percentage of mucinous component and the effect of adjuvant chemotherapy on IMA patients.

METHODS

A total of 145 stage I IMA and 3536 invasive nonmucinous adenocarcinoma patients with R0 resection were included. Based on the percentage of mucinous pattern presented in tumor, IMA were classified into two subgroups: pure mucinous (>90 % invasive mucinous pattern) and mixed mucinous/nonmucinous (≥10 % of each histologic component). Invasive nonmucinous adenocarcinomas were classified into three subgroups: lepidic (LEP), acinar/papillary (ACN/PAP) and solid/micropapillary (SOL/MIP). Disease-free survival (DFS) and overall survival (OS) were assessed and compared among IMA and invasive nonmucinous patients.

RESULTS

For IMA patients, DFS (p = 0.003) was worse for mixed mucinous/nonmucinous compared with pure mucinous subgroup, OS (p = 0.514) was not prognostically different between two groups. There were no significant difference for DFS (p = 0.428) and OS (p = 0.232) between IMA and invasive nonmucinous adenocarcinoma. However, statistical significance were seen for DFS (p < 0.001) and OS (p < 0.001) between 5 major histological subgroups: LEP and pure IMA showed excellent prognosis, mixed mucinous/nonmucinous IMA and SOL/MIP subtypes presented the worst prognosis. No significant survival benefit from adjuvant chemotherapy for IMA patients.

CONCLUSIONS

Mixed mucinous/nonmucinous IMA had a worse DFS compared with pure mucinous. Early stage IMA could not benefit from adjuvant chemotherapy.

KRAS and NKX2-1 Mutations in Invasive Mucinous Adenocarcinoma of the Lung

INTRODUCTION

Mucinous differentiation is observed in a subset of lung adenocarcinomas with unique clinical and pathological features, but the biology of these neoplasms is poorly understood.

METHODS

We apply targeted next-generation sequencing to characterize the mutational profiles of 21 invasive mucinous adenocarcinomas, mixed mucinous/nonmucinous adenocarcinomas, and adenocarcinomas with mucinous features of the lung and validate key findings on 954 additional lung adenocarcinomas from our institution and 514 lung adenocarcinomas from The Cancer Genome Atlas.

RESULTS

Sequencing identifies pathogenic mutations in the oncogenes Kirsten rat sarcoma viral oncogene homolog (KRAS), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), erb-b2 receptor tyrosine kinase 2 (ERBB2), and anaplastic lymphoma receptor tyrosine kinase (ALK) and recurrent mutations in tumor protein p53 (TP53), serine/threonine kinase 11 (STK11), NK2 homeobox 1 (NKX2-1), and SET domain containing 2 (SETD2). In the combined discovery and validation cohorts, we identify nine neoplasms with distinct molecular and pathological features. All are invasive mucinous adenocarcinomas or mixed mucinous/nonmucinous adenocarcinomas with mutations of KRAS and frameshift or nonsense mutations of NKX2-1. Immunohistochemical analysis shows that these neoplasms are associated with altered differentiation states, including loss of expression of the pulmonary marker thyroid transcription factor 1 (also called Nkx2.1) and expression of gastrointestinal markers.

CONCLUSIONS

These findings describe recurrent NKX2-1 mutations in invasive mucinous adenocarcinomas of the lung and support NKX2-1 as a lineage-specific tumor suppressor gene in lung carcinogenesis.