Kyuichi Kadota

Impact of Micropapillary Histologic Subtype in Selecting Limited Resection vs Lobectomy for Lung Adenocarcinoma of 2cm or Smaller

BACKGROUND We sought to analyze the prognostic significance of the new International Association for the Study of Lung Cancer (IASLC), American Thoracic Society (ATS), and European Respiratory Society (ERS) lung adenocarcinoma (ADC) classification for patients undergoing resection for small (≤2cm) lung ADC and to investigate whether histologic subtyping can predict recurrence after limited resection (LR) vs lobectomy (LO). METHODS Comprehensive histologic subtyping was performed according to the IASLC/ATS/ERS classification on all consecutive patients who underwent LR or LO for small lung ADC between 1995 and 2009 at Memorial Sloan-Kettering Cancer Center. Clinical characteristics and pathologic data were retrospectively evaluated for 734 consecutive patients (LR: 258; LO: 476). Cumulative incidence of recurrence (CIR) was calculated using competing risks analysis and compared across groups using Greys test. All statistical tests were two-sided. RESULTS Application of IASLC/ATS/ERS lung ADC histologic subtyping to predict recurrence demonstrates that, in the LR group but not in the LO group, micropapillary (MIP) component of 5% or greater was associated with an increased risk of recurrence, compared with MIP component of less than 5% (LR: 5-year CIR = 34.2%, 95% confidence interval [CI] = 23.5% to 49.7% vs 5-year CIR = 12.4%, 95% CI = 6.9% to 22.1%, P < .001; LO: 5-year CIR = 19.1%, 95% CI = 12.0% to 30.5% vs 15-year CIR = 12.9%, 95% CI = 7.6% to 21.9%, P = .13). In the LR group, among patients with tumors with an MIP component of 5% or greater, most recurrences (63.4%) were locoregional; MIP component of 5% or greater was statistically significantly associated with increased risk of local recurrence when the surgical margin was less than 1cm (5-year CIR = 32.0%, 95% CI = 18.6% to 46.0% for MIP ≥ 5% vs 5-year CIR = 7.6%, 95% CI = 2.3% to 15.6% for MIP < 5%; P = .007) but not when surgical margin was 1cm or greater (5-year CIR = 13.0%, 95% CI = 4.1% to 22.1% for MIP ≥ 5% vs 5-year CIR = 3.4%, 95% CI = 0% to 7.7% for MIP < 5%; P = .10). CONCLUSIONS Application of the IASLC/ATS/ERS classification identifies the presence of an MIP component of 5% or greater as independently associated with the risk of recurrence in patients treated with LR.

A grading system combining architectural features and mitotic count predicts recurrence in stage I lung adenocarcinoma

The International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) has recently proposed a new lung adenocarcinoma classification. We investigated whether nuclear features can stratify prognostic subsets. Slides of 485 stage I lung adenocarcinoma patients were reviewed. We evaluated nuclear diameter, nuclear atypia, nuclear/cytoplasmic ratio, chromatin pattern, prominence of nucleoli, intranuclear inclusions, mitotic count/10 high-power fields (HPFs) or 2.4 mm2, and atypical mitoses. Tumors were classified into histologic subtypes according to the IASLC/ATS/ERS classification and grouped by architectural grade into low (adenocarcinoma in situ, minimally invasive adenocarcinoma, or lepidic predominant), intermediate (papillary or acinar), and high (micropapillary or solid). Log-rank tests and Cox regression models evaluated the ability of clinicopathologic factors to predict recurrence-free probability. In univariate analyses, nuclear diameter (P=0.007), nuclear atypia (P=0.006), mitotic count (P<0.001), and atypical mitoses (P<0.001) were significant predictors of recurrence. The recurrence-free probability of patients with high mitotic count (≥5/10 HPF: n=175) was the lowest (5-year recurrence-free probability=73%), followed by intermediate (2–4/10 HPF: n=106, 80%), and low (0–1/10 HPF: n=204, 91%, P<0.001). Combined architectural/mitotic grading system stratified patient outcomes (P<0.001): low grade (low architectural grade with any mitotic count and intermediate architectural grade with low mitotic count: n=201, 5-year recurrence-free probability=92%), intermediate grade (intermediate architectural grade with intermediate–high mitotic counts: n=206, 78%), and high grade (high architectural grade with any mitotic count: n=78, 68%). The advantage of adding mitotic count to architectural grade is in stratifying patients with intermediate architectural grade into two prognostically distinct categories (P=0.001). After adjusting for clinicopathologic factors including sex, stage, pleural/lymphovascular invasion, and necrosis, mitotic count was not an independent predictor of recurrence (P=0.178). However, patients with the high architectural/mitotic grade remained at significantly increased risk of recurrence (high vs low: P=0.005) after adjusting for clinical factors. We proposed this combined architectural/mitotic grade for lung adenocarcinoma as a practical method that can be applied in routine practice.

Clinical Impact of Immune Microenvironment in Stage I Lung Adenocarcinoma: Tumor Interleukin-12 Receptor β2 (IL-12Rβ2), IL-7R, and Stromal FoxP3/CD3 Ratio Are Independent Predictors of Recurrence

PURPOSE Mounting evidence suggests that tumor-infiltrating immune cells have prognostic value for patients with solid organ malignancies. Our aim was to investigate the prognostic significance of the immune microenvironment in patients with stage I lung adenocarcinoma (ADC). PATIENTS AND METHODS Using tissue microarray and immunohistochemistry, we investigated eight types of tumor-infiltrating immune cells in the tumor nest and tumor-associated stroma as well as tumor expression of five cytokines in a uniform cohort of 956 patients with stage I lung ADC (478 each in training and validation cohorts). RESULTS Although a high density of stromal forkhead box P3 (FoxP3) -positive cells was associated with shorter recurrence-free probability (RFP; P = .043), the relative proportion of stromal FoxP3 to CD3 was a stronger predictor of recurrence (5-year RFP, 85% for high v 77% for low ratio; P = .004). High expression of tumor interleukin-12 receptor β2 (IL-12Rβ2) was associated with better outcome (5-year RFP, 90% for high v 80% for low expression; P = .026), whereas high expression of tumor IL-7R was associated with worse outcome (5-year RFP, 76% for high v 86% for low expression; P = .001). In multivariate analysis, these immune markers were independently associated with recurrence. Although IL-7R remained significant for poor overall survival, all the markers remained prognostic for recurrence in patients with stages IA and IB disease as well as for patients with tumors ≤ 2 cm. CONCLUSION Our investigation confirms the biologic and prognostic significance of the tumor immune microenvironment for patients with stage I lung ADC and provides support for its use to stratify clinical outcome and immunotherapeutic interventions.

Prognostic Immune Markers in Non–Small Cell Lung Cancer

Tumor-associated immune responses have polarized effects in regulating tumor growth. Although a clear association has been shown between the tumor immune response and clinical outcome in colorectal and ovarian cancers, the role of immune markers for stratifying prognosis in non–small cell lung cancer (NSCLC) is less defined. Herein, we review the prognostic significance of published immune markers in the tumor microenvironment and peripheral blood of NSCLC patients. To identify prognostic immune genes, we reviewed all published gene-profiling studies in NSCLC and delineated the significance of immune genes by doing subanalysis on the microarray database of the NIH Directors Challenge study. This first comprehensive review of prognostic immune markers provides a foundation for further investigating immune responses in NSCLC. Clin Cancer Res; 17(16); 5247–56. ©2011 AACR.

Prognostic Significance of Adenocarcinoma in situ, Minimally Invasive Adenocarcinoma, and Nonmucinous Lepidic Predominant Invasive Adenocarcinoma of the Lung in Patients with Stage I Disease

According to the IASLC/ATS/ERS classification, the lepidic predominant pattern consists of 3 subtypes: adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and nonmucinous lepidic predominant invasive adenocarcinoma. We reviewed tumor slides from 1038 patients with stage I lung adenocarcinoma, recording the percentage of each histologic pattern and measuring the invasive tumor size. Tumors were classified according to the IASLC/ATS/ERS classification: 2 were AIS, 34 MIA, and 103 lepidic predominant invasive. Cumulative incidence of recurrence (CIR) was used to estimate the probability of recurrence. Patients with AIS and MIA experienced no recurrences. Patients with lepidic predominant invasive tumors had a lower risk for recurrence (5-y CIR, 8%) than nonlepidic predominant tumors (n=899; 19%; P=0.003). Patients with >50% lepidic pattern tumors experienced no recurrences (n=84), those with >10% to 50% lepidic pattern tumors had an intermediate risk for recurrence (n=344; 5-y CIR, 12%), and those with ⩽10% lepidic pattern tumors had the highest risk (n=610; 22%; P<0.001). CIR was lower for patients with ⩽2 cm tumors than for those with >2 to 3 cm tumors (for both total and invasive tumor size), with the difference more pronounced for invasive tumor size (5-y CIR, 13% vs. 21% [total size; P=0.022] and 12% vs. 27% [invasive size; P<0.001]). Most patients with lepidic predominant adenocarcinoma who experienced a recurrence had potential risk factors, including sublobar resection with close margins (⩽0.5 cm; n=2), 20% to 30% micropapillary component (n=2), and lymphatic or vascular invasion (n=2). It therefore may be possible to identify lepidic predominant adenocarcinomas that carry a low or high risk for recurrence.

Tumor Spread through Air Spaces is an Important Pattern of Invasion and Impacts the Frequency and Location of Recurrences after Limited Resection for Small Stage I Lung Adenocarcinomas

Introduction: Tumor invasion in lung adenocarcinoma is defined as infiltration of stroma, blood vessels, or pleura. Based on observation of tumor spread through air spaces (STAS), we considered whether this could represent new patterns of invasion and investigated whether it correlated with locoregional versus distant recurrence according to limited resection versus lobectomy. Methods: We reviewed resected small (less than or equal to 2 cm) stage I lung adenocarcinomas (n = 411; 1995–2006). Tumor STAS was defined as tumor cells—micropapillary structures, solid nests, or single cells—spreading within air spaces in the lung parenchyma beyond the edge of the main tumor. Competing risks methods were used to estimate risk of disease recurrence and its associations with clinicopathological risk factors. Results: STAS was observed in 155 cases (38%). In the limited resection group (n = 120), the risk of any recurrence was significantly higher in patients with STAS-positive tumors than that of patients with STAS-negative tumors (5-year cumulative incidence of recurrence, 42.6% versus 10.9%; P < 0.001); the presence of STAS correlated with higher risk of distant (P = 0.035) and locoregional recurrence (P = 0.001). However, in the lobectomy group (n = 291), the presence of STAS was not associated with either any (P = 0.50) or distant recurrence (P = 0.76). In a multivariate analysis, the presence of tumor STAS remained independently associated with the risk of developing recurrence (hazard ratio, 3.08; P = 0.014). Conclusion: The presence of STAS is a significant risk factor of recurrence in small lung adenocarcinomas treated with limited resection. These findings support our proposal that STAS should formally be recognized as a pattern of invasion in lung adenocarcinoma.

The clinical significance of lymphangiogenesis and angiogenesis in non-small cell lung cancer patients

BACKGROUND Angiogenesis and lymphangiogenesis have been reported to affect malignant phenotype. METHOD We investigated 147 patients with non-small cell lung cancer (NSCLC). Immunohistochemistry using D2-40 was performed to evaluate lymphatic vessel density (LVD), including Micro-LVD (without lumen), Tubal-LVD (with lumen) and lymphatic vessel invasion (LVI). The intratumoural microvessel density (MVD) was evaluated by CD-34 immunostaining. The expressions of vascular endothelial growth factor-A (VEGF-A) and VEGF-C were also studied. RESULTS Lymphangiogenesis was significantly associated with Micro-LVD (p=0.0003). The VEGF-C expression was significantly associated with the Micro-LVD (p=0.0057). In contrast, the VEGF-A expression was significantly associated with the MVD (p=0.0092). The survival was significantly lower in patients with Micro-LVD-high tumours than in patients with Micro-LVD-low tumours (p=0.0397). Survival was also significantly lower in patients with MVD-high tumours than in patients with MVD-low tumours (p=0.0334). A multivariate analysis demonstrated that the Micro-LVD (p=0.0363) and the MVD (p=0.0232) were independent prognostic factors for NSCLC patients. CONCLUSIONS Lymphangiogenesis, specifically Micro-LVD and angiogenesis are independently associated with a poor prognosis in NSCLC patients.

E2F1 Overexpression Correlates with Thymidylate Synthase and Survivin Gene Expressions and Tumor Proliferation in Non–Small-Cell Lung Cancer

Purpose: We investigated the clinical significance of E2F1 gene expression in relation to its target genes, thymidylate synthase (TS) and Survivin, in case of non–small-cell lung cancer (NSCLC). Experimental Design: One hundred twenty-seven cases of resected NSCLC were analyzed. Quantitative reverse transcription-PCR was done to evaluate the gene expression of E2F1, TS, and Survivin. Immunohistochemistry was done to investigate the protein expression of E2F1, TS, and Survivin. The Ki-67 proliferation index and the apoptotic index using the terminal deoxyribonucleotidyl transferase–mediated dUTP nick-end labeling method were also evaluated. Results:E2F1 gene expression significantly correlated with the Ki-67 proliferation index (r = 0.487; P < 0.0001), although no correlation was observed between E2F1 gene expression and the apoptotic index. With regard to E2F1 target genes, E2F1 gene expression significantly correlated with TS gene expression (r = 0.709; P < 0.0001) and Survivin gene expression (r = 0.403; P < 0.0001). The overall survival rate was significantly lower in patients with high-E2F1 tumors than in those with low-E2F1 tumors (P = 0.0027), especially among patients with stage II to III NSCLCs (P = 0.0188). A Cox regression analysis showed that the E2F1 status was a significant prognostic factor for NSCLC patients (hazard ratio, 2.052; P = 0.0261). Conclusions: The present study revealed that E2F1 gene expression correlates with TS and Survivin gene expressions and tumor proliferation. During the progression of NSCLC, E2F1 overexpression could produce more aggressive tumors with a high proliferation rate and chemoresistance.

Phase II trial of temozolomide in patients with relapsed sensitive or refractory small cell lung cancer, with assessment of methylguanine-DNA methyltransferase as a potential biomarker.

Purpose: This phase II study was conducted to assess the efficacy of temozolomide in patients with relapsed small cell lung cancer (SCLC). Experimental Design: Patients with disease progression after one or two prior chemotherapy regimens received temozolomide at 75 mg/m2/d for 21 days of a 28-day cycle. The primary endpoint was the overall response rate [ORR; complete response (CR) plus partial response (PR)], which was evaluated separately in sensitive and refractory cohorts. In the available tissue, we assessed O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status by PCR and MGMT expression by immunohistochemistry. Results: Sixty-four patients were accrued: 48 patients in the sensitive cohort and 16 in the refractory group. One CR and 10 PRs were noted in sensitive patients [ORR, 23%; 95% confidence interval (CI), 12%–37%]. Two PRs were seen in the refractory cohort (ORR, 13%; 95% CI, 2%–38%). As second- and third-line treatment, the ORR was 22% (95% CI, 9%–40%) and 19% (95% CI, 7%–36%), respectively. Among patients with target brain lesions, 38% had a CR or PR (95% CI, 14%–68%). Grade ≥3 thrombocytopenia and neutropenia were observed in nine patients (14%). A greater number of cases with methylated MGMT had a response compared to those with unmethylated MGMT (38% vs. 7%; P = 0.08). Conclusion: Temozolomide has activity in relapsed SCLC, particularly for brain metastases. Response to temozolomide may correlate with MGMT methylation in SCLC. Clin Cancer Res; 18(4); 1138–45. ©2012 AACR.

The cribriform pattern identifies a subset of acinar predominant tumors with poor prognosis in patients with stage I lung adenocarcinoma: a conceptual proposal to classify cribriform predominant tumors as a distinct histologic subtype

The 2011 International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) lung adenocarcinoma classification emphasizes the prognostic significance of histologic subtypes. However, one limitation of this classification is that the highest percentage of patients (∼40%) is classified as acinar predominant tumors, and these patients display a spectrum of favorable and unfavorable clinical behaviors. We investigated whether the cribriform pattern can further stratify prognosis by histologic subtype. Tumor slides from 1038 patients with stage I lung adenocarcinoma (1995–2009) were reviewed. Tumors were classified according to the IASLC/ATS/ERS classification. The percentage of cribriform pattern was recorded, and the cribriform predominant subtype was considered as a subtype for analysis. The log-rank test was used to analyze the association between histologic variables and recurrence-free probability. The 5-year recurrence-free probability for patients with cribriform predominant tumors (n=46) was 70%. The recurrence-free probability for patients with cribriform predominant tumors was significantly lower than that for patients with acinar (5-year recurrence-free probability, 87%; P=0.002) or papillary predominant tumors (83%; P=0.020) but was comparable to that for patients with micropapillary (P=0.34) or solid predominant tumors (P=0.56). The recurrence-free probability for patients with ≥10% cribriform pattern tumors (n=214) was significantly lower (5-year recurrence-free probability, 73%) than that for patients with <10% cribriform pattern tumors (n=824; 84%; P<0.001). In multivariate analysis, patients with acinar predominant tumors with ≥10% cribriform pattern remained at significantly increased risk of recurrence compared with those with <10% cribriform pattern (P=0.042). Cribriform predominant tumors should be considered a distinct subtype with a high risk of recurrence, and presence (≥10%) of the cribriform pattern is an independent predictor of recurrence, identifying a poor prognostic subset of acinar predominant tumors. Our findings highlight the important prognostic value of comprehensive histologic subtyping and recording the percentage of each histologic pattern, according to the IASLC/ATS/ERS classification with the addition of the cribriform subtype.