Spread Through Air Spaces in Stage I to III Resected Lung Adenocarcinomas: Should the Presence of Spread Through Air Spaces Lead to an Upstaging?

In recent years, the concept of spread through air spaces (STAS) has been discussed as an adverse prognostic factor for lung cancer. The aim of our study is to clarify the prognostic role of STAS in relation to the main recognized prognostic factors in a retrospective cohort of 330 European patients who underwent stages I to III lung adenocarcinoma resection. On univariate analysis, the presence of STAS was related to progression-free survival (PFS; hazard ratio [HR]: 1.48; 95% CI: 1.02-2.19; P = 0.038) and overall survival (OS; HR: 1.61; 95% CI: 1.03-2.52; P = 0.50). On multivariate analysis, STAS was related to PFS (HR: 1.51; 95% CI: 1.00-2.17; P = 0.050) and to OS (HR: 1.67; 95% CI: 1.00-2.81; P = 0.050). We showed that the presence of STAS was associated with lower PFS, equivalent to the next pathologic T stage, especially the median PFS of T3 stages without STAS was at 62.8 months while the median PFS of T3 stages with STAS was at 15.7 months, closer to the median PFS of 17.4 months in T4 stages. To conclude, STAS is an independent prognostic factor of PFS in this European cohort and is close to significance for OS. We suggest that the presence of STAS might lead to an upstaging of lung adenocarcinoma.

Value of immunohistochemistry in crushed areas of pulmonary neuroendocrine carcinoma.

Immunohistochemical demonstration of neuroendocrine differentiation is often performed in routine diagnostic practice for lung neuroendocrine carcinoma. However, these carcinomas are often crushed, especially on small specimens. The value of immunohistochemistry on crushed areas is not known. We aimed to assess the value of immunohistochemical markers in crushed areas. We performed a retrospective study of 299 patients with a diagnosis of pulmonary neuroendocrine carcinoma. We showed that the markers TTF-1, synaptophysin, chromogranin A, CD56, and INSM1 were more often negative in crushed areas compared with well-preserved areas. The proliferation index with anti-Ki67 was decreased but remained on average around 90%. For all markers, the percentage of labeled cells was lower than in the preserved areas. Finally, we show that cases without labeling in the crushed areas and maintained labeling in the non-crushed areas have a lower percentage of labeling than cases without this labeling mismatch. Finally, there were no false positives of these stains. Neuroendocrine markers are valid in crushed areas when positive. However, the percentage of labeled cells may be lower than on preserved areas and lead to false negatives. Finally, the proliferation index, although decreased, remains close to that on preserved areas.

Anti-CK7/CK20 Immunohistochemistry Did Not Associate with the Metastatic Site in TTF-1-Negative Lung Cancer.

Anti-CK7 and anti-CK20 immunohistochemistry is sometimes used to establish a diagnosis of primary lung cancer. We performed a retrospective study on the value of anti-CK7 and anti-CK20 immunohistochemistry in 359 biopsies of patients with suspected lung carcinoma in order to assess the usefulness of these antibodies in the evaluation of lung tumors in biopsies. Our results showed TTF-1 positivity in 73.3% of patients. EGFR mutations and ALK rearrangements were significantly different between TTF-1 positive and TTF-1 negative tumors (p < 0.001 and p = 0.023, respectively). Our results show a significant difference (p < 0.001) between TTF-1 positive and TTF-1 negative carcinomas with a median survival of 21.97 months (CI95% = 17.48−30.9 months) and 6.52 months (CI95% = 3.34−10.3 months), respectively. In the group of TTF-1 negative patients, anti-CK7 and CK20 immunohistochemistry was performed in 70 patients and showed CK7+/CK20- staining in 61 patients (87.1%), CK7-/CK20- in 4 patients (5.7%), CK7+/CK20+ in 3 patients (4.3%), and CK7-/CK20- in 2 patients (2.8%). No specific or molecular pattern was found in these groups of CK7/CK20 combinations. In total, this work brings arguments concerning the uselessness of anti-CK7/CK20 immunohistochemistry in the case of suspicion of primary lung cancer in biopsies.

Spread Through Air Spaces (STAS) Is an Independent Prognostic Factor in Resected Lung Squamous Cell Carcinoma.

Objective: There is no histoprognostic grading for lung squamous cell carcinoma (LUSC). Different prognostic factors have been described in the recent literature and are not always studied in parallel. Our objective was to search for morphological histopathological prognostic factors in LUSC. Materials and Methods: In this single-center retrospective study of 241 patients, all patients with LUSC who underwent surgical excision over a 12-year period were included. The primary endpoint was 5-year overall survival. Results: STAS was present in 86 (35.7%) patients. The presence of Spread Through Air Spaces (STAS) was correlated with tumor location (p < 0.001), pathological stage (p = 0.039), tumor differentiation (p = 0.029), percentage of necrosis (p = 0.004), presence of vascular and/or lymphatic emboli, budding (p = 0.02), single cell invasion (p = 0.002) and tumor nest size (p = 0.005). The percentage of tumor necrosis was correlated with the overall survival at 5 years: 44.6% of patients were alive when the percentage of necrosis was ≥50%, whereas 68.5% were alive at 5 years when the necrosis was <30% (p < 0.001). When vasculolymphatic emboli were present, the percentage of survival at 5 years was 42.5% compared to 65.5% when they were absent (p = 0.002). The presence of isolated cell invasion was correlated with a lower 5-year survival rate: 51.1% in the case of presence, versus 66% in the case of absence (p = 0.02). In univariate analysis, performance status, pathological stage pT or pN, pleural invasion, histopathological subtype, percentage of tumor necrosis, vasculolymphatic invasion, single-cell invasion, budding and tumor nest size correlated with the percentage of survival at 5 years. On multivariate analysis, only STAS > 3 alveoli (HR, 2.74; 95% CI, 1.18−6.33) was related to overall survival. Conclusion: In conclusion, extensive STAS is an independent factor of poor prognosis in LUSC. STAS is correlated with the presence of other poor prognostic factors such as emboli and pleural invasion and would reflect greater tumor aggressiveness.

Preventive tract embolization with gelatin sponge slurry is safe and considerably reduces pneumothorax after CT-guided lung biopsy with use of large 16-18 coaxial needles.

OBJECTIVE: To evaluate the clinical impact of the tract embolization technique using gelatin sponge slurry after percutaneous CT-guided lung biopsy. METHODS: We retrospectively compared coaxial needle CT-guided lung biopsies performed without embolization (100 patients) and with the tract embolization technique using a mixture of iodine and gelatin sponge slurry (105 patients) between June 2012 and July 2020. Uni- and multivariate analyses were performed between groups to determine risk factors of pneumothorax. RESULTS: Patients with gelatin sponge slurry tract embolization had statistically lower rates of pneumothorax ((17.1% vs 39%, p < 0.001). In univariate analysis, tract embolization (OR = 0.32, CI = 0.17-0.61 p<0.001) and nodule size >2 cm (OR = 0.33 CI = 0.14-0.8 p = 0.013) had a protective effect on pneumothorax. The puncture path lengths > 2-20 mm and >20 mm were risk factors for pneumothorax (OR = 3.35 IC = 1.44-8.21 p = 0.006 and OR = 4.36 CI = 1.98-10.29 p<0.001, respectively). In multivariate regression analysis, tract embolization had a protective effect of pneumothorax (OR = 0.25, CI = 0.12-0.51, p < 0.001). The puncture path lengths > 2-20 mm and >20 mm were risk factors for pneumothorax (p = 0.030 and p = 0.002, respectively). CONCLUSIONS: The tract embolization technique using iodinated gelatin sponge slurry is safe and considerably reduces pneumothorax after percutaneous CT-guided lung biopsy. Our results suggest that it could be use in clinical routine. ADVANCES IN KNOWLEDGE: The systemic use of gelatin sponge slurry is safe and reduces considerably the rate of pneumothorax upon needle removal when CT-guided core biopsies are performed using large 16-18G coaxial needles.

Adjuvant chemotherapy for completely resected IIA-IIIA non-small cell lung cancer: compliance to guidelines, safety and efficacy in real-life practice.

Background: Since randomised clinical trials demonstrated a survival benefit of adjuvant chemotherapy (AC) following curative-intent lung surgery, AC has been implemented as a standard therapeutic strategy for patients with a completely resected IIA-IIIA non-small cell lung cancer (NSCLC). Regarding the moderate benefit of AC and the lack of literature on AC use in real-life practice, we aimed to evaluate compliance to guidelines, AC safety and efficacy in a less selected population. Methods: Between January 2009 and December 2014, we retrospectively analysed 210 patients with theoretical indication of AC following curative-intent lung surgery for a completely resected IIA-IIIA NSCLC. The primary objective of this retrospective study was to evaluate compliance to AC guidelines. Secondary objectives included safety and efficacy of AC in real-life practice. Results: Among 210 patients with a theoretical indication of AC, chemotherapy administration was validated in multidisciplinary team (MDT) for 62.4% of them and 117 patients (55.7%) finally received AC. Patient's clinical conditions were the main reasons advanced in MDT for no respect to AC guidelines. Most of the patients received cisplatin-vinorelbine (86.3%) and AC was initiated within 8 weeks following lung surgery for 73.5% of patients. One-half of patients who received AC experienced side effects leading to either dose-intensity modification or treatment interruption. In real-life practice, AC was found to provide a survival benefit over surgery alone. Factors related to daily-life practice such as delayed AC initiation or incomplete AC planned dose received were not associated with an inferior survival. Conclusions: Although AC use might differ from guidelines in real-life practice, this retrospective study highlights that AC can be used safely and remains efficient among a less selected population. In the context of immunotherapy and targeted therapies development in peri-operative treatment strategies, the place of AC has to be precised in the future.

Histopathological typing in diffuse malignant epithelioid mesothelioma: implication for prognosis and molecular basis.

The prognostic impact of tumour grading, cytological and architectural patterns and stromal features in diffuse pleural malignant epithelioid mesothelioma (MEM) has been partly studied but not correlated to molecular features. We performed a retrospective study on 92 MEM in our department in order to assess the prognostic role of architectural and stromal patterns, especially tumour to stroma ratio. Secondly, based on The Cancer Genome Atlas (TCGA) database, we analysed the differentially expressed genes in prognostic groups of interest. Our results showed that tumour grading, tumour to stroma ratio and predominant pattern were related to overall survival, p≤0.001, p=0.01 and p=0.001, respectively. In univariate analysis, for high grade tumours hazard ratio (HR) was 4.75 (2.47-9.16), for stroma poor tumours HR=0.016, for predominant tubular or tubulopapillary pattern HR=0.044. In multivariate analysis, high grade tumours were related to overall survival [HR=3.09 (1.50-6.35), p=0.002] and predominant tubular or tubulopapillary pattern [HR=0.56 (0.32-0.99), p=0.045]. In TCGA analysis, after grading of diagnostic slides, we showed that KRTDAP and CXRCR1 expression was higher in low grade tumours, unlike PDZD7 and GPR176 expression which was higher in high grade tumours. FAM81B had a higher expression in stroma poor tumours. We did not find any differentially expressed genes in the architectural patterns group. Our work suggests that tumour grading is an important parameter in MEM with an underlying genomic basis. The role of tumour to stroma ratio needs to be investigated and might also have a genomic basis.

Predictive resistance factors in lung cancer patients treated with Nivolumab. Retrospective study.

OBJECTIVES: Immunotherapy is the current treatment in non-small cell lung cancer (NSCLC). 20% of patients treated with immunotherapy have a prolonged response. What about the remaining 80%? How can we explain that some patients get no benefit from immunotherapy? MATERIEL AND METHODS: We retrospectively analyzed predictive factors of primary or secondary resistance to immunotherapy in NSCLC patients from 2 French hospitals between 2015 and 2018. Moreover, we evaluated whether PD1 inhibitor had an impact on the antitumor effects of salvage chemotherapy administered after immunotherapy. We chose to focus on taxanes. RESULTS: Ninety-six patients were included in this cohort, 65(68%) patients were considered as having primary resistance and 31(32%) secondary resistance. Resistant populations did not differ. At immunotherapy initiation, median survival was 4.6 months for primary resistant patients (95%CI-4.6-6.8) and 15.6 months (95%CI-9.8-NA) for secondary resistant patients. The disease control rates with taxane were 15% in pre immunotherapy conditions vs 50% in post immunotherapy. Response rates improved regardless of the status of resistance. CONCLUSION: This study enriches data about immunotherapy in real-life in NSCLC. Prognostic resistance factors still seem complicated to identify. The high rate of taxane responders in post immunotherapy in this retrospective cohort support the use of taxane in therapeutic escape.

Histopathological subtyping is a prognostic factor in stage IV lung adenocarcinoma.

Lung adenocarcinoma is a heterogeneous tumor made of different architectural patterns. These tumors are classified into subtypes according to the predominant pattern in the primary tumor because the predominant pattern is related to overall survival. The prognostic role of these subtypes in stage IV disease is not well known, and most lung adenocarcinomas are diagnosed at the stage of metastatic disease. We aimed to evaluate the prognostic role of histopathological subtypes in lung adenocarcinoma metastases in a retrospective study of 253 patients with clinical, histopathological and molecular data. The presence of the solid subtype was related to overall survival (p = 0.045); the median overall survival was 6.8 months (95 % confidence interval (95 %CI) 4.4-9.1) when present and 11.1 months (95 %CI 8.6-21.3) when absent. Thyroid transcription factor 1 (TTF-1) immunohistochemistry was related to overall survival (p < 0.001); the median overall survival was 11.2 months (95 %CI 8.4-17.7) when positive and 4 months (95 %CI 2.3-5.7) when negative. On multivariate analysis, the presence of the solid subtype (p = 0.0036, hazard ratio (HR) 1.55, 95 %CI 1.03-2.34), TTF-1 positivity (p = 0.044, HR 0.64, 95 %CI 0.42-0.98), age <60 years at the time of resection (p = 0.017, HR 1.89; 95 %CI 1.12-3.21), performance status <2 (p = 0.017, HR 0.57; 95 %CI 0.36-0.91), treatment by chemotherapy (p = 0.033, HR 0.54, 95 %CI 0.31-0.95), and treatment by tyrosine kinase inhibitor or immunotherapy (p = 0.013, HR 0.36, 95 %CI 0.17-0.81) were related to overall survival. The evaluation of architectural pattern in metastases in stage IV patients provides further information for physicians about patient prognosis. This information might be included in clinical trials in patients with stage IV lung adenocarcinoma.

Lepidic, Papillary Components and EGFR Mutations are Frequent in Patients With Lung Adenocarcinoma Who are Over 75 Years Old.

Treatment for lung adenocarcinoma frequently diverges from standard treatment in older patients. Clinical, pathologic, and molecular characteristics of lung cancer in patients over 75 years old have not been fully described. The aim of our work was to describe the rate of EGFR, KRAS, BRAF, and HER2 mutations, and ALK rearrangement and pathologic characteristics in patients with lung adenocarcinoma over 75, compared with patients below 75 years old. This is a retrospective study from 2 cohorts: a histopathologic cohort of all consecutively resected lung adenocarcinoma in our institution for patients over 75 (n=54, from 2006 to 2017) compared with patients below 75 years old (n=148, from 2014 to 2017) and a molecular cohort of all stage IIIb or IV lung adenocarcinoma from 2009 to 2017 (n=1611). Papillary and lepidic components were more frequently found in patients over 75 years old (P=0.046 and 0.0078, respectively). The rate of current smokers was lower in older patients (P<0.0001). EGFR mutations were more frequent in patients over 75 than in younger patients: 17% versus 8.1% (P<0.0001). The mutually exclusive KRAS mutation was more frequent in patients below 75 years old than in older patients: 25.8% versus 12.8% (P<0.0001). There was no difference for the proportion of the 2 most frequent EGFR mutations (exon 19 deletion and L858R mutation) (P=0.85) or KRAS-mutated codon (P=0.22) between tumors in younger or older patients. There was no statistically significant difference for the presence of BRAF, HER2 mutations, and ALK rearrangement (P=0.44, 0.71, and 1, respectively). Our work highlights the fact that EGFR mutations are more frequent in patients over 75 years old in our population. We can hypothesize that this difference might be mainly caused by the less frequent occurrence of tobacco-smoking-related lung cancers in the elderly and the presence of a lepidic or papillary component in this age group.

Pathologic Subtypes of Lung Adenocarcinoma Brain Metastasis Is a Strong Predictor of Survival After Resection.

Primary lung adenocarcinoma is classified according to predominant histopathologic architecture into lepidic, papillary, acinar, solid, and micropapillary subtypes. These subtypes are related to overall survival in primary lung adenocarcinoma. The main goal of our work was to evaluate the prognostic impact of this classification on surgical resection of brain adenocarcinoma metastases in 97 patients with surgically resected brain metastases of lung adenocarcinoma from 2008 to 2017. Histopathologic subtype is associated with overall survival (P=0.0085): 30.1±5.6 months for papillary-predominant pattern, 26.5±6.3 months for acinar-predominant pattern, 13.8±1.4 months for solid pattern, 11.6±10.1 for micropapillary pattern. A "low grade" group comprising acinar and papillary-predominant pattern tumors showed a longer overall survival (28.5±4.1 mo) when compared with high-grade-predominant pattern (solid and micropapillary patterns) (13.7±1.4 mo), P=0.0011. On multivariate analysis, age below 55 years at the time of resection (hazard ratio, 3.56; 95% confidence interval, 1.12-11.31) and groups of architectural patterns (hazard ratio, 4.25; 95% confidence interval, 1.83-9.9) were related to overall survival (P=0.031 and 0.00078, respectively). Predominant architectural pattern evaluated on the surgical specimen of brain metastasis is a major prognostic factor of overall survival in metastatic lung adenocarcinoma.

Nuclear grading, BAP1, mesothelin and PD-L1 expression in malignant pleural mesothelioma: prognostic implications.

For malignant pleural mesothelioma (MPM), histopathological subtype is one of the most important prognostic factors. Several immunohistochemical stains whose expressions have possible therapeutic implications have been identified in MPM such as BAP1, mesothelin and PD-L1. The aim of our work was to evaluate the clinical significance and prognostic implications of BAP1, mesothelin and PD-L1 expression in 117 patients with a diagnosis of MPM who were diagnosed in our institution between 2002 and 2017. We also correlated this immunohistochemical profile to a recently described nuclear grading and to histopathological subtype. Mesothelin expression, BAP1 loss and PD-L1 expression were associated with histopathological subtype (p < 0.0001), BAP1 loss was more frequent in epithelioid subtype whereas PD-L1 expression was more frequent in non-epithelioid subtype. For epithelioid MPM, BAP1 expression was associated with overall survival (p = 0.034), with a longer survival when BAP1 expression is lost. Necrosis and nuclear grading are associated with overall survival (p = 0.0048 and <0.0001, respectively), with longer survival when necrosis was absent and for grade I. For non-epithelioid MPM, overall survival was not related to clinical, histopathological or immunohistochemical expression of BAP1, mesothelin or PD-L1. In multivariate analysis, grade I for nuclear grading was an independent prognostic factor associated with overall survival (p < 0.0001). In epithelioid and non-epithelioid MPM, we analysed overall survival in subgroups with combined mesothelin, BAP1 and PD-L1 expression. In epithelioid MPM, BAP1 retained/mesothelin negativity/PD-L1 > 1%, and BAP1 retained/mesothelin positivity/PD-L1 > 1% profiles, are associated with shorter overall survival. In non-epithelioid MPM, BAP1 loss/mesothelin negativity/PD-L1 > 1% is associated with shorter overall survival. Our work confirms that nuclear grading in epithelioid MPM is a strong and independent prognosis factor. Moreover, this study on several promising immunohistochemical stains whose expressions have possible therapeutic implications identifies subgroups with a poor prognosis.

Histopathologic features predict survival in diffuse pleural malignant mesothelioma on pleural biopsies.

Malignant pleural mesothelioma is a rare tumor with a poor prognosis. The only universally recognized pathological prognostic factor is histopathological subtype with a shorter survival in non-epithelioid subtypes. Recently, a grading of epithelioid mesothelioma on surgical resection has been proposed. The aim of our work is to assess the prognostic role of several histopathological factors on a retrospective cohort of 116 patients diagnosed as a pleural mesothelioma for more than 95% of patients on pleural biopsy. Our work shows that mitotic count <3/10 HPF (p < 0.0001), the lack of necrosis (p = 0.0379), mild nuclear atypia (p = 0.0054), the lack of atypical mitoses (p = 0.0265), a nucleoli size <3 µm (p = 0.0139), and a nucleoli absent or visible at 200× or higher magnification (p = 0.0170) are significantly associated with a better median overall survival in epithelioid mesothelioma. The presence of atypical mitoses was found to be related to a worse median survival in non-epithelioid mesothelioma. Mitotic count, necrosis, nuclear atypia, and nucleoli size are not associated with overall survival in non-epithelioid mesothelioma. Our work highlights that histopathological prognostic factors can be assessed on pleural biopsies and can predict reliably median overall survival. This is of interest in order to define subgroups of patients who could benefit of different therapies and select patients who could benefit of surgical excision.