Clinicopathological and immunohistochemical features of lung invasive mucinous adenocarcinoma based on computed tomography findings

Radiological Features of Primary Pulmonary Invasive Mucinous Adenocarcinoma Based on 312 Consecutive Patients

BACKGROUND

The aim of this study is to investigate the radiological features of primary pulmonary invasive mucinous adenocarcinoma (IMA) in a relatively large population to help improve its further understanding and its accuracy of initial diagnosis.

METHODS

This retrospective study included consecutive patients with pathologically confirmed primary pulmonary IMA from January 2019 to December 2021. According to tumor morphology, IMAs were divided into regular nodule/mass, irregular, and large consolidative types. According to tumor density, IMAs were divided into solid, halo, part-solid, pure ground-glass, and cystic types. ANOVA, chi-square, or Fisher exact tests were used to analyze the differences in radiological and clinicopathological characteristics of IMA according to morphological and density subtypes.

RESULTS

We analyzed 312 patients. Pulmonary IMA tended to occur in the elderly, with a slightly higher number of women than men. IMA showed a predominance in the lower lobe and adjacent to pleura. IMA of regular nodule/mass, irregular, and large consolidative types accounted for 80.8% (252/312), 13.8% (43/312), and 5.4% (17/312), respectively. Solid, halo, part-solid, pure ground-glass, and cystic IMAs accounted for 55.8% (174/312), 28.2% (88/312), 11.2% (35/312), 1.3% (4/312), and 3.5% (11/312), respectively. The lobulated (76.9%), spiculated (63.5%), and air bronchogram (56.7%) signs were common in IMA. Dead branch sign (88.2%), angiogram sign (88.2%), and satellite nodules/skipping lesions (47.1%) were common in large-consolidative-type IMA. Kirsten rat sarcoma viral oncogene mutations were common (56.1%), whereas epidermal growth factor receptor mutations were relatively rare (2.3%).

CONCLUSIONS

Pulmonary IMA of regular nodule/mass type and solid type were the most common at the initial diagnosis. Detailed radiological features can aid in the differential diagnosis of IMA.

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.

Prognostic factors for invasive mucinous adenocarcinoma of the lung: systematic review and meta-analysis

BACKGROUND

Invasive mucinous adenocarcinoma of the lung (IMA) is a unique and rare subtype of lung adenocarcinoma with poorly defined prognostic factors and highly controversial studies. Hence, this study aimed to comprehensively identify and summarize the prognostic factors associated with IMA.

METHODS

A comprehensive search of relevant literature was conducted in the PubMed, Embase, Cochrane, and Web of Science databases from their inception until June 2023. The pooled hazard ratio (HR) and corresponding 95% confidence intervals (CI) of overall survival (OS) and/or disease-free survival (DFS) were obtained to evaluate potential prognostic factors.

RESULTS

A total of 1062 patients from 11 studies were included. In univariate analysis, we found that gender, age, TNM stage, smoking history, lymph node metastasis, pleural metastasis, spread through air spaces (STAS), tumor size, pathological grade, computed tomography (CT) findings of consolidative-type morphology, pneumonia type, and well-defined heterogeneous ground-glass opacity (GGO) were risk factors for IMA, and spiculated margin sign was a protective factor. In multivariate analysis, smoking history, lymph node metastasis, pathological grade, STAS, tumor size, and pneumonia type sign were found to be risk factors. There was not enough evidence that epidermal growth factor receptor (EGFR) mutations, anaplastic lymphoma kinase (ALK) mutations, CT signs of lobulated margin, and air bronchogram were related to the prognosis for IMA.

CONCLUSION

In this study, we comprehensively analyzed prognostic factors for invasive mucinous adenocarcinoma of the lung in univariate and multivariate analyses of OS and/or DFS. Finally, 12 risk factors and 1 protective factor were identified. These findings may help guide the clinical management of patients with invasive mucinous adenocarcinoma of the lung.

[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.

Clinicopathologic Features and Survival Outcomes of Primary Lung Mucinous Adenocarcinoma Based on Different Radiologic Subtypes

BACKGROUND

Primary lung mucinous adenocarcinomas (LMAs) could be subclassified as the pure-solid, part-solid, and pneumonic types according to the findings of high-resolution computed tomography. This study aimed to expound on the clinicopathologic, radiologic, and prognostic characteristics of LMAs based on radiologic classification within a large set of patients.

METHODS

From November 2009 to December 2016, this study enrolled 294 resected LMAs, which were divided into the pure-solid (n = 169), part-solid (n = 87), and pneumonic (n = 38) types. The clinicopathologic and radiologic characteristics of the tumors were evaluated, and patient prognosis was determined through follow-up evaluation. Survival outcomes were calculated by Kaplan-Meier curves and compared using log-rank tests. The prognostic impact of clinicopathologic variables, including radiologic presentations, were evaluated by establishing a Cox proportional hazards model.

RESULTS

The LMAs were infrequently associated with lymph node metastasis (5.4 %), lymphatic/vascular invasion (4.4 %), or visceral pleural invasion (5.1 %). During the median 71-month follow-up period, recurrence was observed in 62 patients and death in 44 patients. The patients with pneumonic-type LMAs had a poorer prognosis (5-year recurrence-free survival [RFS], 23.7 %; 5-year overall survival [OS], 44.7 %) than those with the pure-solid type (RFS, 83.2 %; OS, 100 %) or part-solid type (RFS, 93.7 %; OS, 100 %). Besides, lymph node metastasis, emphysema, and clinical T stage were independent predictors of RFS and OS.

CONCLUSION

Solitary-type LMA patients had excellent prognoses, whereas the survival outcomes for pneumonic-type LMA patients were dismal. Furthermore, pneumonic-type LMA patients were prone to intrapulmonary metastasis by means of aerogenous dissemination rather than distant metastasis.

Immunostimulatory and anti-inflammatory impact of Fragaria ananassa methanol extract in a rat model of cadmium chloride-induced pulmonary toxicity

Cadmium is an extremely dangerous heavy metal that can lead to disastrous consequences in all organisms. Several natural remedies reduce the toxicities of experimentally generated metals in animals. Strawberry Fragaria ananassa contains several bioactive compounds that may mitigate heavy-metal toxicity. The study aim was to evaluate the ability of a strawberry fruit methanol extract (SE) to reduce Cd toxicity and to identify and quantify the active constituents of SE. Forty Wistar rats were classified into four groups: the control group- 1 ml saline IP; SE group- 100 mg of SE/kg rats orally; cadmium (Cd) group-2 mg CdCl2/kg body weight/IP daily; and treated group- SE given 1 hour before Cd administration. Administration of Cd induced several histopathological and immunohistochemical alterations in lung sections. Biochemical analysis of lung homogenates and mRNA levels of antioxidants and inflammatory cytokines indicated significant changes to the risk profile. SE administration significantly decreased the oxidative stress, inflammation, tissue damage, the mean area percentage of collagen fibers, and positive immuno-expressions of TNF-α and NF-κB induced by CdCl2. Moreover, the MDA, TNF-α, GM-CSF, and IL-1β levels in Cd-exposed rat lung tissue were significantly lower in the SE-treated group than in the Cd-group. SE significantly augmented lung GSH, SOD, HO-1, GPx-2, and Nrf2 levels in Cd-exposed rats. SE mitigated Cd-caused oxidative stress and lung inflammation. Therefore, regularly consuming a strawberry-rich diet could benefit general health and help prevent and treat diseases.

Surgical resection of a large invasive mucinous adenocarcinoma: A case report

Invasive mucinous adenocarcinoma often presents with pneumonia-like findings on imaging, which complicates its diagnosis. This case demonstrates that aggressive bronchoscopy is useful for examining infiltrating shadows in the lung field and large tumors occupying the entire lung lobe should be treated cautiously when lung parenchyma develops.

Invasive mucinous adenocarcinoma of the lung: clinicopathological features, 18F-FDG PET/CT findings, and survival outcomes

OBJECTIVE

Invasive mucinous adenocarcinoma (IMA) is a rare subtype of lung adenocarcinoma. This study aimed to retrospectively evaluate the clinicopathological features, ¹⁸F-FDG PET/CT findings, and prognosis of IMA of the lung, as well as to investigate the associations among these variables, to improve the management of such patients.

METHODS

Clinicopathological and ¹⁸F-FDG PET/CT characteristics of 72 patients with pathologically confirmed IMA of the lung were retrospectively collected and investigated, and their predictive efficacy on progression-free survival (PFS) was evaluated.

RESULTS

The median age of the enrolled 72 patients was 61 years (range, 26-79 years), and the male-to-female ratio was 1:1.25. According to the radiological morphology of IMA, solidary nodule/mass type (n = 59, 81.9%) was the most common, followed by GGO type (n = 8, 11.1%) and pneumonia type (n = 5, 6.9%). Lobulated or spiculated margin and pleural traction were the most common radiological signs. The median SUVmax of IMA lesions was 3.0, ranging from 0.5 to 23.1. Higher SUVmax was observed in IMA with non-GGO type, clinical symptom, advanced stage, lobulated margin, pleural traction or spread through air spaces (STAS) (P < 0.05). Moreover, higher SUVmax was related to larger tumor size in non-pneumonia-type IMA (r = 0.708, P < 0.001). The median PFS was 21.3 months, and the 12-, 24- and 36-month PFS rates were 89.8%, 83.3% and 75.5%, respectively. A poorer PFS was significantly associated with SUVmax ≥ 3, advanced stage and STAS.

CONCLUSION

¹⁸F-FDG PET/CT combined with clinicopathological characteristics can aid the diagnosis and prognostic evaluation of lung IMA, which could provide guidance for the appropriate management of such patients.

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.

CT Features of Stage IA Invasive Mucinous Adenocarcinoma of the Lung and Establishment of a Prediction Model

Objective

To investigate computed tomography (CT) features of stage IA invasive mucinous adenocarcinoma (IMA) of the lung and establish a predictive model.

Methods

Fifty-three lesions from 53 cases of stage IA IMA between January 2017 and December 2019 were examined, while 141 lesions from 141 cases of invasive non-mucinous lung adenocarcinoma (INMA) served as control cases. Univariate analysis was performed to compare differences in demographics and CT features between the two groups, and multivariate logistic regression analysis was performed to determine primary influencing factors of solitary nodular IMA. A risk score prediction model was established based on the regression coefficients of these factors, and receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive performance of the model.

Results

Univariate analysis showed that age, nodule type, maximum nodule diameter, tumor lung interface, lobulation, spiculation, air bronchogram or vacuolar signs, and abnormal vascular changes differed significantly between the two groups (p < 0.05). Compared to INMA, spiculation of IMA was relatively longer and softer. Multivariate logistic regression analysis showed that nodule type, indistinct tumor lung interface, air bronchogram or vacuolar signs, and abnormal vascular changes were the primary influencing factors. A prediction model based on the regression coefficients of these factors was established. ROC curve analysis indicated that the area under the curve was 0.882 (p < 0.05).

Conclusion

Compared to INMA, solitary peripheral stage IA nodular IMA were more common in older patients; they more frequently had indistinct tumor lung interface and air bronchogram or vacuolar signs on CT; spiculation was relatively longer and softer; our risk score prediction model based on nodule type, tumor lung interface, air bronchogram or vacuolar signs, and abnormal vascular changes was established with good predictive efficacy for solitary nodular IMA.

Recurrence dynamics after curative surgery in patients with invasive mucinous adenocarcinoma of the lung

Background

We investigated the patterns and timing of recurrence and death as well as prognostic factors based on clinicopathological and radiological factors in patients who underwent surgical treatment for invasive mucinous adenocarcinoma (IMA).

Methods

We reviewed clinicopathological findings including spread through air spaces (STAS) and CT findings of IMA such as morphology, solidity, margin, well-defined heterogeneous ground-glass opacity, CT angiogram, and air bronchogram signs from 121 consecutive patients who underwent surgical resection. Prognostic factors for disease-free survival (DFS) and overall survival (OS) were identified. Hazard rate analyses were performed for the survival dynamics.

Results

T stage (hazard ratio [HR] = 4.102, p = 0.03), N stage (N2 vs. N0, HR = 7.653, p < 0.001), and consolidative CT morphology (HR = 3.556, p = 0.008) remained independent predictors for DFS. Age (HR = 1.110, p = 0.002), smoking (HR = 12.893, p < 0.001), T stage (HR = 13.005, p = 0.006), N stage (N2 vs. N0, HR = 7.653, p = 0.004), STAS (HR = 7.463, p = 0.008), and consolidative CT morphology (HR = 6.779, p = 0.007) remained independent predictors for OS. Consolidative morphology, higher T and N stage, and presence of STAS revealed initial sharp peaks after steep decline of the hazard rate curves for recurrence or death in follow-up period.

Conclusions

Consolidative morphology, higher T and N stage, smoking, and STAS were indicators of significantly greater risk of early recurrence or death in patients with IMA. Thus, these findings could be incorporated into future surveillance strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-022-01208-5.

Pneumonic-type lung adenocarcinoma with different ranges exhibiting different clinical, imaging, and pathological characteristics

Background

Pneumonic-type lung adenocarcinoma (PLADC) with different ranges might exhibit different imaging and clinicopathological features. This study divided PLADC into localized PLADC (L-PLADC) and diffuse PLADC (D-PLADC) based on imaging and aimed to clarify the differences in clinical, imaging, and pathologic characteristics between the two new subtypes.

Results

The data of 131 patients with L-PLADC and 117 patients with D-PLADC who were pathologically confirmed and underwent chest computed tomography (CT) at our institute from December 2014 to December 2020 were retrospectively collected. Patients with L-PLADC were predominantly female, non-smokers, and without respiratory symptoms and elevated white blood cell count and C-reactive protein level, whereas those with D-PLADC were predominantly male, smokers, and had respiratory symptoms and elevated white blood cell count and C-reactive protein level (all p < 0.05). Pleural retraction was more common in L-PLADC, whereas interlobular fissure bulging, hypodense sign, air space, CT angiogram sign, coexisting nodules, pleural effusion, and lymphadenopathy were more frequent in D-PLADC (all p < 0.001). Among the 129 patients with surgically resected PLADC, the most common histological subtype of L-PLADC was acinar-predominant growth pattern (76.7%, 79/103), whereas that of D-PLADC was invasive mucinous adenocarcinoma (80.8%, 21/26). Among the 136 patients with EGFR mutation status, L-PLADC had a significantly higher EGFR mutation rate than D-PLADC (p < 0.001).

Conclusions

L-PLADC and D-PLADC have different clinical, imaging, and pathological characteristics. This new imaging-based classification may help improve our understanding of PLADC and develop personalized treatment plans, with concomitant implications for patient outcomes.

Feasibility and Safety of Neoadjuvant Alectinib in Pulmonary Invasive Mucinous Adenocarcinoma with ALK Rearrangement: Case Report and Literature Review

Background

Pulmonary invasive mucinous adenocarcinoma (IMA) is a rare variant of lung adenocarcinoma that rarely shows anaplastic lymphoma kinase (ALK) rearrangement. Alectinib (tyrosine kinase inhibitors) has been listed as category 1 recommendations for advanced ALK + NSCLC first-line therapy due to low toxicity and excellent efficacy, and its median progression-free survival is 34.8 months. Here, we report a case of a patient with ALK-rearranged lung IMA who showed favorable results to neoadjuvant alectinib.

Case

A 67-year-old man with no history of smoking was diagnosed with clinical stage as IIIB invasive mucinous adenocarcinoma based on clinical symptoms, chest CT and pathological findings. The anaplastic lymphoma kinase (ALK) fusion status was assessed by real-time PCR. After acquiring informed consent from the patient, we offered neoadjuvant alectinib at a dosage of 150 mg twice per day for three cycles (84 days), all lesions were undetectable on chest CT. Later, a thoracoscopic left lobectomy was performed. The postoperative pathological showed that a small amount of tumor cells remained, and the TNM stage was downstaged as T1aN0M0 IA.

Conclusion

To our knowledge, this is the first case discussing the treatment of ALK-rearranged IMA of the lung with neoadjuvant alectinib. Alectinib is an effective ALK inhibitor, and in cases of lung adenocarcinoma with ALK rearrangement, alectinib treatment is a reasonable and priority option. Neoadjuvant alectinib may be clinically feasible and well tolerated in locally advanced NSCLC.

Radiological and clinical features of screening-detected pulmonary invasive mucinous adenocarcinoma

 

OBJECTIVES

The current understanding of pulmonary invasive mucinous adenocarcinoma is largely based on studies of advanced stage patients and data about early-stage invasive mucinous adenocarcinoma are sparse. We evaluated the radiological and clinical features of screening-detected early-stage invasive mucinous adenocarcinoma (SD-IMA).

METHODS

Data from 91 patients who underwent surgical treatment for SD-IMA (≤3 cm) from 2013 to 2019 were reviewed retrospectively. Data on radiological characteristics, clinicopathological findings, recurrence and survival were obtained. Disease-free survival rate was analysed.

RESULTS

Radiologically, SD-IMAs presented as a pure ground-glass nodule (6.6%), part-solid nodule (38.5%) or solid (54.9%). Dominant locations were both lower lobes (74.7%) and peripheral area (93.4%). The sensitivity of percutaneous needle biopsy was 78.1% (25/32). Lobectomy was performed in 70 (76.9%) patients, and sublobar resection in 21 (23.1%) patients. Seventy-three (80.2%), 15 (16.5%) and 3 (3.3%) patients had pathological stage IA, IB and IIB or above, respectively. Seven patients developed recurrence, and 3 died due to disease progression. Pleural seeding developed exclusively in 2 patients who underwent needle biopsy. The 5-year disease-free survival rate was 89.4%. The disease-free survival rates at 5 years were 86.3% in the lobectomy group and 100% in the sublobar resection group.

CONCLUSIONS

SD-IMAs were mostly radiologically invasive nodules. SD-IMAs showed favourable prognosis after surgical treatment.

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.

Clinical Relevance of PD-L1 Expression and CD8+ T Cells' Infiltration in Patients With Lung Invasive Mucinous Adenocarcinoma

BACKGROUND

Invasive mucinous adenocarcinoma (IMA) of the lung is a rare and distinct subtype of adenocarcinoma. At present, people have no idea whether IMA patients can benefit from immunotherapy and target therapy; thus there is an urgent need to clarify the immune microenvironment and genetic characteristics of this cohort.

METHODS

A total of 31 IMA patients matched with 27 non-mucinous adenocarcinoma (non-IMA) patients were enrolled in this study, and clinical data was collected. The expression of PD-L1, CD8+ tumor-infiltrating lymphocytes (TILs) and ALK was determined by immunohistochemistry. Polymerase Chain Reaction was used to determine the mutations of EGFR. The Chi-square test, Kaplan-Meier method and Cox proportional hazard regression model were used to explore the correlations between these clinicopathological variables, survival and identify risk factors.

RESULTS

Of the patients with IMA 9.7% (3/31) revealed positive PD-L1 expression and 35.5% (11/31) showed CD8+ TIL infiltration, which were markedly lower than that of non-IMA group [PD-L1: 48.1% (13/27); CD8: 81.5% (22/27)]. Moreover, five (16.1%) patients in IMA group and 10 (37.0%) patients in non-IMA group had EGFR mutations, and nine (29.0%) patients in IMA group and zero (0.0%) patient in non-IMA group had ALK rearrangements. Additionally, we observed that IMA patients with CD8+ TIL infiltration had a worse prognosis than CD8-negative group (P = 0.024). Multivariate analyses showed that CD8 was an independent prognostic factor for patient's survival (HR = 5.60, 95% CI: 1.35-23.22, P = 0.017).

CONCLUSION

Patients with IMA have down-regulated expression of PD-L1 and less CD8+ TIL infiltration in tumor microenvironment. Besides, a lower frequency of EGFR mutations was detected in patients with IMA than non-IMA patients while a higher rate of ALK rearrangements was found. Our results provide important reference for therapy of lung IMA.

Development and validation of a nomogram for predicting survival of pulmonary invasive mucinous adenocarcinoma based on surveillance, epidemiology, and end results (SEER) database

Background

Lung cancer remains the leading cause of cancer death globally. In 2015, the cancer classification guidelines of the World Health Organization were updated. The term “invasive mucinous adenocarcinoma (IMA)” aroused people’s attention, while the clinicopathological factors that may influence survival were unclear.

Methods

Data of IMA patients was downloaded from SEER database. Kaplan-Meier methods and log-rank tests were used to compare the differences in OS and LCSS. The nomogram was developed based on the result of the multivariable analysis. The discrimination and accuracy were tested by Harrell’s concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve and decision curve analyses (DCA). Integrated discrimination improvement (IDI) index was used to evaluate the clinical efficacy.

Results

According to multivariate analysis, the prognosis of IMAs was associated with age, differentiation grade, TNM stage and treatments. Surgery might be the only way that would improve survival. Area under the curve (AUC) of the training cohort was 0.834and 0.830 for3-and 5-year OS, respectively. AUC for 3-and 5-year LCSS were separately 0.839 and 0.839. The new model was then evaluated by calibration curve, DCA and IDI index.

Conclusion

Based on this study, prognosis of IMAs was systematically reviewed, and a new nomogram was developed and validated. This model helps us understand IMA in depth and provides new ideas for IMA treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07811-x.

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.

Invasive mucinous adenocarcinoma of the lung: Serial CT findings, clinical features, and treatment and survival outcomes

BACKGROUND

Invasive mucinous adenocarcinoma (IMA) of the lung is a rare and distinct subtype of adenocarcinoma that can appear as airspace opacities on computed tomography (CT). In daily practice, we have occasionally encountered spontaneous regression of airspace opacities (SRAs) without treatment on serial CTs in patients with IMAs, which has not previously been described in the literature. Here, we describe serial CT findings with emphasis on SRAs in relation to clinicopathological features and treatment outcomes in patients with IMAs.

METHODS

A total of 46 patients with pathologically-confirmed IMAs of the lung from January 2013 to June 2018 were included. Serial CT scans were reviewed and the patients were classified into SRA and no-SRA groups according to the presence of SRA. Radiological features, clinicopathological characteristics, and treatment outcomes were compared between the SRA and no-SRA groups.

RESULTS

A total of 32 patients were included in the no-SRA group and 14 patients in the SRA group. IMAs in the SRA group were mostly pneumonic (P < 0.001), larger (P < 0.001), multifocal (P = 0.001), and showed higher stage (P < 0.001) on initial CT. Of seven patients who died during follow-up, six were from the SRA group (P < 0.001). Mean overall survival for all IMAs was 86.6 months (range, 0-110 months), and the SRA group showed significantly worse overall survival (P < 0.001).

CONCLUSIONS

IMAs of the lung showing SRAs on serial CTs are larger and multifocal, and tend to be pneumonic in type on initial CT. Patients present at a higher stage of disease, with higher mortality rate and reduced overall survival.

KEY POINTS

SIGNIFICANT FINDINGS OF THE STUDY: Invasive mucinous adenocarcinomas (IMAs) of the lung can show spontaneous regression of airspace opacities (SRAs) on serial CTs, without being correlated to the administration of anticancer drugs. IMAs that showed SRAs demonstrated reduced overall survival in patients.

WHAT THIS STUDY ADDS

When airspace opacities show regression on CT, IMA should still be included in the differential diagnosis. A more careful application of RECIST 1.1 is needed in the assessment of tumor response of IMAs.

Unusual lung involvements of invasive mucinous adenocarcinoma with chylothorax

A 77-year-old man who had a persistent productive cough for one month was admitted to our hospital. Chest computed tomography (CT) revealed subpleural nodular opacities, irregular pleural thickening with bilateral basal predominance, and a small right pleural effusion. Aspirated fluid was exudative and had the appearance of chylothorax without malignant cells. Surgical lung biopsy specimen showed focal proliferation of neoplastic epithelial cells with lepidic-predominant pattern and abundant mucus in the alveolar spaces, consistent with invasive mucinous adenocarcinoma (IMA). The results of PD-L1 expression and the EGFR, ALK, ROS1, and BRAF mutation status analyzed by next generation sequencer were all negative. IMA should be considered in the differential diagnosis of subpleural micronodular opacities accompanied by pleural effusion (chylothorax) on chest CT. KEY POINTS: Significant findings of the study This case showed subpleural micronodular opacities and chylothorax as unusual chest computed tomography (CT) patterns for invasive mucinous adenocarcinoma (IMA). What this study adds Invasive mucinous adenocarcinoma (IMA) should be considered in the differential diagnosis of subpleural micronodular opacities accompanied by pleural effusion on chest CT.

Annexin A2 Expression in the Aerogenous Spread of Pulmonary Invasive Mucinous Adenocarcinoma with Gastric Lineage

Spread through air spaces (STAS) is a unique form of lung cancer progression associated with a worse prognosis. However, the mechanisms underlying STAS and the associated proteins remain unclear. Annexin A2 (ANX A2), which is a membrane-binding protein involved in cell adhesion, is known to promote cancer invasion. In this report, we describe the immunohistochemical analysis of ANX A2 expression in an invasive mucinous adenocarcinoma (IMAC) resected from a 63-year-old man in whom the tumor cells had detached from the alveolar wall and exhibited STAS. At the detachment site, we observed cytoplasmic ANX A2 positivity on the basal side and in the exfoliative gap, as well as reduced collagen IV positivity expression. This biomarker pattern suggested an IMAC with gastric lineage. We hypothesize that ANX A2 is secreted from the basal sides of tumor cells and induces tumor cell detachment by degrading the basement membrane. A further comparison of this case with an IMAC with nongastric lineage suggested the following probabilities: (1) ANX A2 likely contributes to STAS in a manner that is dependent on its subcellular localization. (2) Both the subcellular localization of ANX A2 and the detachment site depend on tumor cell characteristics, including the biomarker immunophenotype.

Proportion of goblet cell is associated with malignant potential in invasive mucinous adenocarcinoma of the lung

Invasive mucinous adenocarcinoma (IMA) is a newly classified variant of lung adenocarcinoma. The aim of this study was to examine the correlation between the proportion of goblet cells and the clinicopathological characteristics of IMA. Ninety-nine patients with stage I IMA were included in this study. We estimated prognostic impact of goblet cell proportion. We classified them into two groups: the cases with a high goblet cell proportion (HGP, goblet cell proportion ≥80%) and the cases with a low goblet cell proportion (LGP, goblet cell proportion ≤30%), and compared the expression levels of five cancer progression markers and the number of tumor-promoting stromal cells between the two groups. Univariate and multivariate analysis revealed that the goblet cell proportion was a prognostic factor for recurrence free survival (P < 0.01) and overall survival (P = 0.01). The expression levels of the cancer stem cell-related marker, ALDH-1, and proliferation-related marker, geminin were significantly higher in the LGP group than in the HGP group. CD204+ tumor-associated macrophages were significantly more in the LGP stroma than the HGP stroma. Our current study indicated that the proportion of goblet cells was correlated with the malignant potential in surgically resected IMA.

Invasive mucinous adenocarcinoma of the lung

Invasive mucinous adenocarcinoma (IMA) is a unique histological subtype of adenocarcinoma. Due to its low incidence rates, survival data for IMA is scarce and often contradictory. The clinical manifestations of IMA are not precise as compared to other adenocarcinomas, with some patients having bronchial mucus overflow. Difference in immunohistochemical expression levels is present in IMA and invasive non-mucinous adenocarcinomas (INMA). Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations are more frequent in IMAs, while epidermal growth factor receptor (EGFR) mutations are relatively rare. This makes it distinct from the other more common adenocarcinomas. Neuregulin 1 (NRG1) gene fusions are considered important therapeutic targets for IMA, suggesting that Afatinib may be an effective drug to treat IMA. However, IMA prognosis remains controversial.

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.

Clinical characteristics and prognosis of nonsurgically treated patients with pneumonic-type adenocarcinoma

Pneumonic-type adenocarcinoma (P-ADC) is a subtype of lung adenocarcinoma with high mortality, which often requires lobectomy surgery. Nonsurgically treated P-ADC patients usually have more advanced or complex conditions, which remain poorly understood and pose a major challenge in clinical management. We aimed to describe the clinical profiles and prognosis of non-surgically treated P-ADC patients. We enrolled 71 patients with pathologically proven P-ADC from a university hospital in China. Clinical and laboratory data were retrieved from medical record. Their median age was 62 years, including 45% men and 35% smokers. Clinical manifestations were dominated by cough, sputum, and dyspnea. Main chest imaging features included nodules, shadow, consolidation, and air bronchogram. Nearly half or more of patients showed higher levels of inflammation and cancer biomarkers including cytokeratin-19-fragment (CYFRA 21-1) and carcinoembryonic antigen (CEA). Majority of patients were classified at the stage IIIB or IV. Palliative care was the most popular treatment option but provided a shorter overall survival compared to tyrosine kinase inhibitor therapy, standard chemotherapy, and sequential therapy while there were no significant differences in the survival among the latter 3 options. Higher serum CEA was associated with longer survival and better prognosis while higher serum CYFRA 21-1 could predict a poor prognosis. Detailed understanding the clinical characteristics and prognostic factors in nonsurgically treated P-ADC may allow the identification of patients with particular risk factors and initiation of early and specific treatment in order to optimize outcomes.

Can Quantitative Volumetric Analysis Predict Tumor Recurrence in the Patients with Mucinous Adenocarcinoma of the Lung After Surgical Resection?

RATIONALE AND OBJECTIVES

Mucinous adenocarcinoma (MAC) is a distinct histologic variant subtype of lung adenocarcinomas. However, detailed radiologic findings and prognostic factors are still poorly understood. Thus, this study aimed to investigate the prognostic value of quantitative volumetric analysis of the computed tomography images of patients with MAC after. surgical resection.

MATERIALS AND METHODS

Semiautomatic segmentation from computed tomography images of 60 patients with pathologically confirmed MAC was performed and retrospectively reviewed. The main cutoff value in Hounsfield Units (HU) to predict tumor recurrence was defined by receiver-operating curve analysis. Solid volume of mass (SVM) was defined as the volume of HU greater than this cutoff, and solid ratio (Sratio) was defined as SVM divided by total volume. Each parameter was compared to clinicopathologic characteristics and maximum standardized uptake value. Disease-free survival (DFS) was assessed and was compared among patients. Univariate and multivariate Cox regression was performed to predict DFS of MAC.

RESULTS

The cutoff value of HU as determined by ROC analysis was 20 HU. SVM and Sratio were positively correlated with the maximum standardized uptake and pathologic invasion size, respectively (p < 0.001). SVM and Sratio were significantly higher in the recurrence group than in the no-recurrence group (p < 0.001). Multivariate Cox proportional hazards regression analysis revealed that the SVM (Hazard Ratio 1.016; 95% Confidence Interval 1.000-1.032; p = 0.048) and Sratio (Hazard Ratio 29.136; 95% Confidence Interval 1.419-598.191; p = 0.029) were independent significant predictors of DFS.

CONCLUSION

Quantitative volumetric parameters can predict the prognosis of patients with MAC after surgical resection.

Primary Pulmonary Colloid Adenocarcinoma: How Can We Obtain a Precise Diagnosis?

A 76-year-old asymptomatic man was found to have a mass in the right lower lung field. Although the presence of a mucinous component in the majority of the tumor was shown by magnetic resonance imaging, the presence of cancer cells was suspected by contrast enhancement on computed tomography (CT) and based on the partial accumulation in the marginal regions of the tumor on fluorodeoxyglucose-positron emission tomography (FDG-PET). A transbronchial lung biopsy was non-diagnostic, but resection of the mass resulted in a diagnosis of colloid adenocarcinoma. The findings from combined contrast CT and FDG-PET may raise the suspicion of colloid adenocarcinoma and prompt the consideration of surgical resection.