Thyroid transcription factor-1 expression is an independent predictor of recurrence and correlates with the IASLC/ATS/ERS histologic classification in patients with stage I lung adenocarcinoma

BACKGROUND

In the current study, the authors investigated whether thyroid transcription factor-1 (TTF-1) expression is correlated with the International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and whether it stratifies patients with stage I lung adenocarcinoma with respect to disease recurrence.

METHODS

Patients with stage I lung adenocarcinoma were classified according to the IASLC/ATS/ERS classification. Tissue microarrays were constructed and immunostaining for TTF-1 was performed. A total of 452 cases were available for analysis. Tumors were dichotomized based on the intensity of nuclear TTF-1 expression as negative (score of 0) or positive (score of 1-3). The cumulative incidence of recurrence (CIR) was used to estimate disease recurrence probabilities.

RESULTS

TTF-1 expression was identified in 92% of patients, including 100% of patients with minimally invasive or lepidic-predominant adenocarcinoma, 94% of patients with acinar-predominant adenocarcinoma, 98% of patients with papillary-predominant adenocarcinoma, 93% of patients with micropapillary-predominant adenocarcinoma, 86% of patients with solid-predominant adenocarcinoma, 67% of patients with colloid-predominant adenocarcinoma, and 47% of patients with invasive mucinous carcinoma. The CIR for patients with negative TTF-1 expression (n = 34 patients; 5-year CIR, 40%) was significantly higher than that for patients with positive TTF-1 expression (n = 418 patients; 5-year CIR, 15%) (P < .001). Among the patients with intermediate-grade tumors, the CIR for patients with negative TTF-1 expression (n = 16 patients; 5-year CIR, 45%) was significantly higher than that for patients with positive TTF-1 expression (n = 313 patients; 5-year CIR, 14%) (P < .001). On multivariate analysis, negative TTF-1 expression was found to be significantly correlated with an increased risk of disease recurrence (hazards ratio, 2.55; P = .009).

CONCLUSIONS

TTF-1 expression was found to be an independent predictor of disease recurrence, stratifying intermediate-grade tumors into 2 prognostic subsets, and it correlates with the IASLC/ATS/ERS classification.

FDG-PET SUVmax combined with IASLC/ATS/ERS histologic classification improves the prognostic stratification of patients with stage I lung adenocarcinoma

BACKGROUND

We investigated the association between the newly proposed International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and (18)F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET), and whether the combination of these radiologic and pathologic factors can further prognostically stratify patients with stage I lung adenocarcinoma.

METHODS

We retrospectively evaluated 222 patients with pathologic stage I lung adenocarcinoma who underwent FDG-PET scanning before undergoing surgical resection between 1999 and 2005. Patients were classified by histologic grade according to the IASLC/ATS/ERS classification (low, intermediate, or high grade) and by maximum standard uptake value (SUVmax) (low <3.0, high ≥3.0). The cumulative incidence of recurrence (CIR) was used to estimate recurrence probabilities.

RESULTS

Patients with high-grade histology had higher risk of recurrence (5-year CIR, 29% [n = 25]) than those with intermediate-grade (13% [n = 181]) or low-grade (11% [n = 16]) histology (p = 0.046). High SUVmax was associated with high-grade histology (p < 0.001) and with increased risk of recurrence compared to low SUVmax (5-year CIR, 21% [n = 113] vs. 8% [n = 109]; p = 0.013). Among patients with intermediate-grade histology, those with high SUVmax had higher risk of recurrence than those with low SUVmax (5-year CIR, 19% [n = 87] vs. 7% [n = 94]; p = 0.033). SUVmax was associated with recurrence even after adjusting for pathologic stage (p = 0.037).

CONCLUSIONS

SUVmax on FDG-PET correlates with the IASLC/ATS/ERS classification and can be used to stratify patients with intermediate-grade histology, the predominant histologic subtype, into two prognostic subsets.

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 mm(2), 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.

Quantitating pathologic response to neoadjuvant chemotherapy in KRAS-mutated versus nonmutated lung cancers

7014

Background: Trials of neoadjuvant chemotherapy in non-small cell lung cancers (NSCLC) have demonstrated that pathologic response correlates with downstaging and survival. There is controversy as to whether KRAS mutated patients (pts) have the same benefit with adjuvant chemotherapy as non-mutated pts however the impact of KRAS mutations on response to neoadjuvant therapy has not been reported. Methods: Pts with resectable stage I-III non-squamous NSCLCs were treated with 4 cycles of cisplatin, docetaxel, and bevacizumab, followed by surgical resection. Tumors were tested for KRAS mutations. Percent treatment effect (necrosis, inflammation, fibrosis) was quantified histologically. Pts were followed until disease recurrence and/or death. Binary variables were compared using the Fisher’s Exact Test. Survival was assessed by pathological response based on the literature (≥90 vs <90%) using the Kaplan-Meier method, stratified by stage (IB-IIB vs. III) and by KRAS mutation. Results: We accrued 51 pts. 34/51 (67%) had clinical stage IIIA disease. 48 had molecular testing: 14/48 (29%) had KRAS mutations and 4/48 (8%) had EGFR mutations. The median follow-up was 2 years (yr) (range, 3-63 months). 41 pts had resection and analysis for pathological response. The 2 yr disease free survival (DFS) and overall survival (OS) were superior in the 11/41 (27%) with ≥90% versus those with <90% treatment effect: DFS 91% vs. 56%, p=0.029 and OS 100% vs. 60%, p=0.013. These outcomes remained significant when adjusted for stage. For pts with KRAS mutations, 0 of 10 tumors analyzed had ≥90% treatment effect whereas 11 of 31 (35%) pts with wild-type KRAS had ≥90%, p=0.039. There was an inferior median OS for KRAS mutated pts (22 months) compared to pts without a known KRAS mutation, (Not Reached, p=0.03). Conclusions: Following neoadjuvant chemotherapy, pts with tumors having ≥90% necrosis had improved survival. There were no patients with KRAS mutation that achieved ≥90% treatment effect in response to cisplatin, docetaxel, and bevacizumab. Adaptive adjuvant trial strategies to improve upon outcomes of those with <90% necrosis at resection and new approaches specifically targeting KRAS-mutated NSCLCs are needed.

Phase II trial of bevacizumab, irinotecan, cisplatin, and radiation as preoperative therapy in esophageal adenocarcinoma

4061

Background: Preop chemo and radiotherapy (RT) with weekly irinotecan (I), cisplatin (C) and 5040 cGy is tolerable and active [Cancer, in press]. Bevacizumab (B) + weekly I/C in advanced esophagogastric cancer increased response rate and PFS without an increase in toxicity [JCO 24: 5201; 2006]. In a phase II trial in esophageal adenocarcinoma (EA) we combed B + I/C with RT as preop therapy. A toxicity analysis after 10 patients (pts) undergoing surgery indicated no unexpected toxicity with B [JCO 27: Abstract 4573; 2009], and we completed a planned accrual of 33 pts. Methods: Pts had resectable distal esophageal or Siewert’s I or II EA, T2-3 or N1 staged by EUS, PET, and CT scan. Induction chemo: I: 50-65 mg/m2 + C: 30 mg/m2 weeks 1,2,4,5, B: 7.5 mg/kg weeks 1 and 4; Chemort: 180 cGy daily fractions to 5040 cGy, I/C weeks 7,8,10,11+ B weeks 7,10. Esophagectomy was planned 6-8 weeks after RT. Postop: B: 7.5 mg/kg every 3 weeks for 8 cycles. Results: 33 pts were enrolled. 26 male: 7 female; distal esophagus 11 (33%), GEJ 22 (67%); 21 T3N1 (64%); 10 T3N0 (30%); 2 T2N0-1 (6%). 25/33 pts went to surgery (76%), 24 had R0 resection (73%). Pathologic CR 5 pts (15%). 8 pts did not going to surgery: 2 for adverse events (9%, 1 CVA due to patent foramen ovale, 1 esophageal perforation due to endoscopic biopsy), 6 for progressive disease (18%). 21/24 pts (88%) received adjuvant B, 20 (95%) completed all cycles. Grade 3/4 toxicity in 30 evaluable pts during chemort: 24% neutropenia, 3% neutropenic fever, 23% esophagitis, 13% dehydration, 13% thrombocytopenia, 7% pulmonary embolism, 3% nausea/vomiting. Surgical complications: 3 anastomotic leaks (12%), 4 respiratory failure (16%), 1 pulmonary embolism (4%), 2 post op deaths (8%). At a median follow up of 20 months, PFS was 14 months and OS was 30 months. Conclusions: The addition of B to preop chemoRT in EA was tolerable without increase in treatment toxicity or surgical complications. There was no suggestion of improved pathologic CR, PFS, or OS with the addition of B to I/C/RT. Evaluation of B in phase III trials of chemort does not appear warranted. Supported by a grant from Genentech.

Prospective study of tumor suppressor gene (TSG) methylation as a prognostic biomarker in surgically resected non-small cell lung cancer (NSCLC)

7066

Background: In the New England Journal of Medicine, Brock et al. (2008) published a nested case-control study which tested the association between early recurrence of NSCLC after surgical resection, and TSG promoter methylation in tumor and lymph nodes detected by methylation-specific PCR (MSP). They reported that promoter methylation of the TSGs p16, CDH13, RASSF1A, and APC was significantly associated with early recurrence in 51 patients with stage I NSCLC compared to matched patients without early recurrence. We attempted to confirm these findings. Methods: In a prospective study, fresh frozen tumor tissue was acquired after surgical resection in 107 patients with stage I-IIIA NSCLC between 2003-2008. The promoter methylation status of the same 4 genes examined by Brock, et al (p16, CDH13, RASSF1A, APC), as well as 6 additional TSGs (MGMT, WIF-1, METH-2, GSTP1, SOCS3, DAPK) were assessed in the tumor tissue using quantitative MSP (MethyLight assay), with any amount of methylation scored as positive. Methylation status was correlated with clinical features, pathologic stage, disease-free survival (DFS), and overall survival (OS). Results: No significant associations were observed between promoter methylation of individual TSGs and DFS. No significant associations were observed between the number of methylated TSGs and DFS, or OS. Increased RASSF1A methylation was observed in poorly-differentiated and undifferentiated tumors compared to tumors that were well- or moderately-differentiated (p=0.031). Increased WIF-1 methylation and GSTP1 methylation were associated with increasing T (p=0.01) and N stage (p=0.028), respectively. Squamous cell carcinomas (SQCCs) were characterized by increased p16 methylation (p=0.0314) and decreased APC methylation (p=0.0146) compared to tumors of non-SQCC histologies. Conclusions: In this prospective study, we did not confirm that the promoter methylation of p16, CDH13, RASSF1A, and APC, or 6 other TSGs, was prognostic for early recurrence in surgically resected NSCLC.

Clinical characteristics of patients with malignant pleural mesothelioma (MPM) harboring somatic BAP1 mutations

1541

Background: Efforts to elucidate tumorigenic mutations in MPM are essential to advance therapy. We reported a 23% incidence of somatic mutations in BRCA1-associated protein-1 (BAP1) in 53 patients with MPM (Bott et al. Nat Genet 2011). Germline BAP1 mutations were also reported in two families with a predisposition to mesothelioma and uveal melanoma (Testa et al. Nat Genet 2011). While BAP1 somatic mutations are more common in poor prognosis uveal melanoma (84% class 2, 4% class 1; Harbour et al. Science 2010), the significance of these mutations in MPM is unknown. Therefore, we analyzed the clinical characteristics of patients with somatic BAP1 mutations in order to describe this newly identified subpopulation. Methods: We reviewed the charts of 121 patients with tumors tested for somatic BAP1 mutations. Results: Patient characteristics are in the Table. Twenty percent harbored somatic BAP1 mutations. Other than the percent of current or former smokers (75% BAP1 mutations, 42% BAP1 wild-type, p=0.006), no other clinical feature was significantly different among those with and without BAP1 mutations. Among 53 samples analyzed for NF2 mutation and p16 deletion, no correlation was seen with BAP1 mutation. Conclusions: Somatic BAP1 mutations occur in about 20% of MPM tumors. Aside from smoking history, no other differences in clinical characteristics or outcomes were noted in the BAP1 mutated cases. Similar efforts are needed to describe the features of germline mutations in order to define this new cancer predisposition syndrome. We are planning a prospective trial to further evaluate the prevalence of germline BAP1 mutations, and we are also exploring the therapeutic implications. [Table: see text]

Mesothelin overexpression promotes mesothelioma cell invasion and MMP-9 secretion in an orthotopic mouse model and in epithelioid pleural mesothelioma patients

PURPOSE

Mesothelin (MSLN) is a tumor-associated antigen, being investigated as a biomarker and therapeutic target in malignant pleural mesothelioma (MPM). The biologic function of MSLN overexpression in MPM is unknown. We hypothesized that MSLN may promote tumor invasion in MPM, a tumor characterized primarily by regional aggressiveness and rare distant metastases.

EXPERIMENTAL DESIGN

Human and murine MPM cells with MSLN forced expression and short hairpin RNA knockdown were examined for proliferation, invasion, and matrix metalloproteinase (MMP) secretion. The influence of MSLN overexpression on MPM cell invasion was assessed in an orthotopic mouse model and in patient samples.

RESULTS

MSLN expression promotes MPM cell invasion and MMP secretion in both human and murine MPM cells. In an orthotopic MPM mouse model characterized by our laboratory, MPM cells with MSLN overexpression preferentially localized to the tumor invading edge, colocalized with MMP-9 expression, and promoted decreased survival without an increase in tumor burden progression. In a tissue microarray from epithelioid MPM patients (n = 139, 729 cores), MSLN overexpression correlated with higher MMP-9 expression at individual core level. Among stage III MPM patients (n = 72), high MSLN expression was observed in 26% of T2 tumors and 51% of T3 tumors.

CONCLUSIONS

Our data provide evidence elucidating a biologic role for MSLN as a factor promoting tumor invasion and MMP-9 expression in MSLN expressing MPM. As regional invasion is the characteristic feature in MSLN expressing solid cancers (MPM, pancreas, and ovarian), our observations add rationale to studies investigating MSLN as a therapeutic target.

A nuclear grading system is a strong predictor of survival in epitheloid diffuse malignant pleural mesothelioma

Epithelioid mesothelioma is the most prevalent subtype of diffuse malignant pleural mesothelioma in which only staging is prognostic for survival. In this study of epithelioid diffuse malignant pleural mesothelioma, we investigate the prognostic utility of nuclear features. The slides of 232 epithelioid diffuse malignant pleural mesothelioma patients (14 stage I, 54 stage II, 130 stage III, and 34 stage IV) from a single institution were reviewed for the following seven nuclear features: nuclear atypia, nuclear/cytoplasmic ratio, chromatin pattern, intranuclear inclusions, prominence of nucleoli, mitotic count, and atypical mitoses. MIB-1 immunohistochemistry was performed using tissue microarray, and MIB-1 labeling index was recorded as the percentage of positive tumor cells. Median overall survival of all patients was 16 months and correlated with nuclear atypia (P<0.001), chromatin pattern (P=0.031), prominence of nucleoli (P<0.001), mitotic count (P<0.001), and atypical mitoses (P<0.001) by univariate analysis. Multivariate analysis revealed nuclear atypia (P=0.012) and mitotic count (P<0.001) as independent prognostic factors, and these two factors were utilized to create a three-tier nuclear grade score. The resulting nuclear grade stratified patients into three distinct prognostic groups: grade I (n=107, median overall survival=28 months), grade II (n=91, 14 months), and grade III (n=34, 5 months). Not only was nuclear grade an independent predictor of overall survival (P<0.001), but it was also a stronger discriminator of survival than all currently available factors. Furthermore, nuclear grade was associated with time to recurrence (P=0.004) in patients who underwent complete surgical resection (n=159). MIB-1 labeling index correlated with mitotic count (P<0.001) and nuclear atypia (P=0.037) and stratified overall survival (P<0.001) and time to recurrence (P=0.048), confirming the prognostic value of the nuclear grade. Nuclear grading in epithelioid mesothelioma provides a simple, practical, and cost-effective prognostic tool that better stratifies clinical outcome and time to recurrence than currently available clinicopathologic factors.

Phase II trial of bevacizumab, irinotecan, cisplatin, and radiation as preoperative therapy in esophageal adenocarcinoma

67

Background: Preop chemo and radiotherapy (RT) with weekly irinotecan (I), cisplatin (C) and 5040 cGy is tolerable and active [Cancer, in press]. Bevacizumab (B) + weekly I/C in advanced esophagogastric cancer increased response rate and PFS without an increase in toxicity [JCO 24: 5201; 2006]. In a phase II trial in esophageal adenocarcinoma (EA) we combined B + I/C + RT as preop therapy. A toxicity analysis after 10 patients (pts) undergoing surgery indicated no unexpected toxicity with B [JCO 27: Abstract 4573; 2009]. We completed a planned accrual of 33 pts.

Methods: Pts had resectable Siewert’s I or II EA, T2-3 or N1 staged by EUS, PET, and CT scan. Induction chemo: I 50-65 mg/m2 + C 30 mg/m2 weeks 1,2,4,5, B 7.5 mg/kg weeks 1 and 4; Chemort: 180 cGy daily fractions to 5040 cGy, I/C weeks 7,8,10,11+ B weeks 7,10. Esophagectomy was planned 6-8 weeks after RT. Postop: B 7.5 mg/kg every 3 weeks for 8 cycles.

Results: 33 pts were enrolled. 26 male: 7 female; 13 Siewert I (39%): 20 Siewert II (61%); 21 T3N1 (64%); 10 T3N0 (30%); 2 T2N0-1 (6%). 25/33 pts went to surgery (76%), 24 had R0 resection (73%). Pathologic CR 4/33 pts (12%). 8 pts did not go to surgery: 2 for adverse events (9%, 1 CVA due to patent foramen ovale, 1 esophageal perforation due to endoscopic biopsy), 5 for progressive disease (15%). 21/24 pts (88%) received adjuvant B, 20 (95%) completed all cycles. Grade 3/4 toxicity in 30 evaluable pts during chemort: 27% neutropenia, 3% neutropenic fever, 23% esophagitis, 13% dehydration, 13% thrombocytopenia, 7% pulmonary embolism, 3% nausea/vomiting. Surgical complications: 3 anastamotic leaks (12%), 4 respiratory failure (16%), 1 pulmonary embolism (4%), 2 post op deaths (8%). At a median follow up of 20 months, PFS was 14 months and OS was 30 months.

Conclusions: The addition of B to preop chemoRT in EA was tolerable without increase in treatment toxicity or surgical complications. There was no suggestion of improved pathologic CR, PFS, or OS with the addition of B to I/C/RT. Evaluation of B in phase III trials of chemort does not appear warranted. Supported by a grant from Genentech.

Tissue and serum mesothelin are potential markers of neoplastic progression in Barrett's associated esophageal adenocarcinoma

BACKGROUND

Mesothelin is overexpressed in several malignancies and is purportedly a specific marker of malignant transformation. In this pilot study, we investigated whether tissue and serum mesothelin are potential markers of neoplastic progression in Barrett's esophagus (BE) and in esophageal adenocarcinoma (EAC).

METHODS

Mesothelin expression was retrospectively evaluated in normal, BE, and EAC tissue from surgically resected esophageal specimens (n = 125). In addition, soluble mesothelin-related peptide (SMRP) levels were measured in serum.

RESULTS

Normal esophageal mucosa did not express mesothelin. BE tissue with high-grade dysplasia specifically expressed mesothelin, whereas BE tissue with low-grade or without dysplasia did not. Fifty-seven (46%) EAC tumors were positive for mesothelin. EAC tumors with BE expressed mesothelin more often than those without BE (58% vs. 35%, P = 0.01). SMRP levels were elevated in 70% of EAC patients (mean = 0.89 nmol/L; range: 0.03-3.77 nmol/L), but not in patients with acid reflux and/or BE.

CONCLUSIONS

Mesothelin is commonly expressed in BE-associated EAC. On the basis of this pilot study, a prospective study is under way to evaluate tissue and serum mesothelin which are potential markers of neoplastic progression in BE and in EAC (NCT01393483).

IMPACT

Current surveillance methods in Barrett's esophagus are invasive and neither cost-effective nor sensitive. This pilot study suggests that serum mesothelin is a marker of neoplastic transformation in BE and may provide a noninvasive method to improve identification of malignant transformation.

Occult metastases in lymph nodes predict survival in resectable non-small-cell lung cancer: report of the ACOSOG Z0040 trial

PURPOSE

The survival of patients with non-small-cell lung cancer (NSCLC), even when resectable, remains poor. Several small studies suggest that occult metastases (OMs) in pleura, bone marrow (BM), or lymph nodes (LNs) are present in early-stage NSCLC and are associated with a poor outcome. We investigated the prevalence of OMs in resectable NSCLC and their relationship with survival.

PATIENTS AND METHODS

Eligible patients had previously untreated, potentially resectable NSCLC. Saline lavage of the pleural space, performed before and after pulmonary resection, was examined cytologically. Rib BM and all histologically negative LNs (N0) were examined for OM, diagnosed by cytokeratin immunohistochemistry (IHC). Survival probabilities were estimated using the Kaplan-Meier method. The log-rank test and Cox proportional hazards regression model were used to compare survival of groups of patients. P < .05 was considered significant.

RESULTS

From July 1999 to March 2004, 1,047 eligible patients (538 men and 509 women; median age, 67.2 years) were entered onto the study, of whom 50% had adenocarcinoma and 66% had stage I NSCLC. Pleural lavage was cytologically positive in only 29 patients. OMs were identified in 66 (8.0%) of 821 BM specimens and 130 (22.4%) of 580 LN specimens. In univariate and multivariable analyses OMs in LN but not BM were associated with significantly worse disease-free survival (hazard ratio [HR], 1.50; P = .031) and overall survival (HR, 1.58; P = .009).

CONCLUSION

In early-stage NSCLC, LN OMs detected by IHC identify patients with a worse prognosis. Future clinical trials should test the role of IHC in identifying patients for adjuvant therapy.

Neoadjuvant and adjuvant chemotherapy in resected pulmonary large cell neuroendocrine carcinomas: a single institution experience

BACKGROUND

Pulmonary large cell neuroendocrine carcinomas (LCNEC) are aggressive neoplasms with poor prognosis. The role of neoadjuvant and adjuvant therapies in these tumors remains uncertain.

METHODS

We performed a retrospective review of a prospective database. Kaplan-Meier estimates of overall survival (OS) were determined and compared across prognostic factors using log-rank analysis and the Cox proportional hazards model.

RESULTS

One hundred patients with resected LCNEC were identified from 1992 to 2008. Of these, 54% were male and 98% current or former smokers (mean 60.3 pack-years). Twenty-two patients received neoadjuvant platinum chemotherapy with a response rate of 68% (15 of 22). Eighty percent (80 of 100) underwent lobectomy and 11% (11 of 100) pneumonectomy with a 90% (90 of 100) complete resection (R0) rate. Seventy-one percent (71 of 100) were stage I-II, and 20 of 71 received platinum adjuvant chemotherapy. Mean OS was 40 months. Univariate factors associated with decreased OS included male gender (p = 0.007), increasing tumor (T) stage (p = 0.004), and stage III-IV disease (p = 0.04). Stage IB patients fared significantly worse than IA (p = 0.006). Multivariate analyses identified male gender (hazard ratio [HR] 2.3, p = 0.007), comorbid pulmonary disease (HR 2.3, p = 0.012), and pathologic stage (HR = 2.2, p = 0.011) as associated with risk of death. Univariate analysis in stage IB-IIIA completely resected (R0) patients receiving combination platinum-based induction and (or) adjuvant chemotherapy showed a trend toward improved OS (median survival 7.4 vs 2 years, p = 0.052).

CONCLUSIONS

The LCNEC has a high response rate to platinum-based neoadjuvant chemotherapy. Resected advanced-stage patients receiving combination neoadjuvant and (or) adjuvant chemotherapy may have a survival advantage. These therapies should be considered in resectable patients with LCNEC.

Expression profiling and identification of potential molecular targets for therapy in pulmonary large-cell neuroendocrine carcinoma

The prognosis for patients with large-cell neuroendocrine carcinoma (LCNEC) of the lung is extremely poor, and an optimal treatment has not yet been established. It has been recently reported that molecular-targeted therapies, such as tyrosine kinase inhibitors for epidermal growth factor receptor (EGFR), are effective in patients with lung carcinoma. In efforts to improve the prognosis of patients with LCNEC, we analyzed gene expression, gene mutations and immunohistochemical (IHC) expression of known molecular targets in LCNECs, and compared the expression to that of lung adenocarcinomas (ACs). Thirteen patients with primary LCNEC and 14 patients with AC were analyzed. We evaluated IHC expression for c-KIT, human epidermal growth factor receptor type 2 (HER2) and vascular endothelial growth factor (VEGF), gene mutations for EGFR, K-ras and c-kit, and gene expression using fluorescence in situ hybridization for EGFR. In cases with LCNEC, the IHC expression of c-KIT, HER2 and VEGF was 76.9, 30.8 and 100%, respectively. There was a significant difference in the IHC expression of c-KIT and HER2 between the LCNEC and AC cases. Two cases of LCNEC had overexpression of HER2, and the frequency of EGFR gene mutations was higher in the the AC group, with only a single EGFR mutation (exon 18) identified in the LCNEC group. Although LCNEC had a higher rate of expression of c-KIT by IHC, no c-kit gene mutations were found. These findings suggest a potential role for anti-VEGF-, anti-c-KIT- and possibly anti-HER2-targeted agents in the treatment of LCNEC.

Chronic inflammation in tumor stroma is an independent predictor of prolonged survival in epithelioid malignant pleural mesothelioma patients

This study aims to determine whether a semi-quantitative assessment of inflammatory response in tumor and stroma on routine hematoxylin and eosin-stained (H&E) slides can predict survival in patients with epithelioid malignant pleural mesothelioma (MPM). H&E sections of 175 epithelioid MPM specimens from a single institution (1989-2009) were reviewed. Patients who received neoadjuvant chemotherapy were excluded from analysis. Each tumor was histologically assessed for acute and chronic inflammatory response both within the tumor and the stromal component. Inflammatory response was graded: low (none to mild infiltrate) or high (moderate to severe infiltrate). Log-rank test and Cox proportional hazards regression were used to investigate the association between the degree of inflammation (acute/tumor, acute/stroma, chronic/tumor, and chronic/stroma) and overall survival (OS). Patients with high chronic inflammatory response in stroma (n = 59) had improved survival compared to low (n = 116) (median OS = 19.4 vs. 15.0 months, P = 0.01). This prognostic stratification remained significant in stage III patients (median OS = 16.0 vs. 9.3 months, P = 0.03). In multivariate analysis, chronic inflammation in stroma was an independent predictor of survival (HR = 0.659, 95% CI 0.464-0.937, P = 0.02). While high degree of chronic inflammatory cell infiltration in the stromal component was associated with improved overall survival, degree of other inflammatory responses did not show significant correlation with OS. Our study for the first time investigates inflammatory response in tumor and stroma and not only suggests the prognostic value of inflammatory response in epithelioid MPM but also provides rationale for investigation of immunotherapy to benefit epithelioid MPM patients.

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 Director's Challenge study. This first comprehensive review of prognostic immune markers provides a foundation for further investigating immune responses in NSCLC.

Incidence of EGFR exon 19 deletions and L858R in tumor specimens from men and cigarette smokers with lung adenocarcinomas

PURPOSE

EGFR mutations underlie the sensitivity of lung cancers to erlotinib and gefitinib and can occur in any patient with this illness. Here we examine the frequency of EGFR mutations in smokers and men.

METHODS

We determined the frequency of EGFR mutations and characterized their association with cigarette smoking status and male sex.

RESULTS

We tested 2,142 lung adenocarcinoma specimens for the presence of EGFR exon 19 deletions and L858R. EGFR mutations were found in 15% of tumors from former smokers (181 of 1,218; 95% CI, 13% to 17%), 6% from current smokers (20 of 344; 95% CI, 4% to 9%), and 52% from never smokers (302 of 580; 95% CI, 48% to 56%; P < .001 for ever v never smokers). EGFR mutations in former or current smokers represented 40% of all those detected (201 of 503; 95% CI, 36% to 44%). EGFR mutations were found in 19% (157 of 827; 95% CI, 16% to 22%) of tumors from men and 26% (346 of 1,315; 95% CI, 24% to 29%) of tumors from women (P < .001). EGFR mutations in men represented 31% (157 of 503; 95% CI, 27% to 35%) of all those detected.

CONCLUSION

A large number of EGFR mutations are found in adenocarcinoma tumor specimens from men and people who smoked cigarettes. If only women who were never smokers were tested, 57% of all EGFR mutations would be missed. Testing for EGFR mutations should be considered for all patients with adenocarcinoma of the lung at diagnosis, regardless of clinical characteristics. This strategy can extend the use of EGFR tyrosine kinase inhibitors to the greatest number individuals with the potential for substantial benefit.