Relevance of the novel IASLC/ATS/ERS classification of lung adenocarcinoma in advanced disease.

Since the International Association for the Study of Lung Cancer (IASLC), American Thoracic Society (ATS) and European Respiratory Society (ERS) reported a new lung adenocarcinoma (ADC) classification, several groups have validated its association with prognosis in early stage disease. To our knowledge, there are no studies in advanced disease. We reviewed 313 patients with invasive lung ADC who were re-classified using the new IASLC/ATS/ERS criteria. Patients received platinum-based chemotherapy. Clinical characteristics, EGFR mutations, response and progression-free survival (PFS) after chemotherapy and overall survival were analysed. ADCs were classified as lepidic 7.4%, acinar 44.7%, papillary 10.1%, micropapillary 3.5% and solid 34.2%. When patterns were lumped into groups, response rates and PFS to platinum-based chemotherapy were better in high-grade ADC (micropapillary, papillary and solid-predominant) versus intermediate-grade ADC (lepidic and acinar-predominant) (36.9% versus 25.4% p=0.034 and 6.4 versus 5.5 months p=0.009, respectively). Overall survival was better in high-grade ADC (25 versus 16.8; p=0.023). Factors associated with better overall survival were Eastern Cooperative Oncology Group (0-1), EGFR mutations and high-grade ADC. Prognostic differences found with the new classification in early disease may not apply to patients with advanced disease. Unlike in early stages, patients with high-grade ADC have longer overall survival compared with intermediate-grade ADC, probably due to a better response to chemotherapy.

Usefulness of serum carcinoembryonic antigen (CEA) in evaluating response to chemotherapy in patients with advanced non small-cell lung cancer: a prospective cohort study.

BACKGROUND: High serum carcinoembryonic antigen (CEA) levels are an independent prognostic factor for recurrence and survival in patients with non-small cell lung cancer (NSCLC). Its role as a predictive marker of treatment response has not been widely characterized. METHODS: 180 patients with advanced NSCLC (stage IIIB or Stage IV), who had an elevated CEA serum level (>10 ng/ml) at baseline and who had no more than one previous chemotherapy regimen, were included. CEA levels were measured after two treatment cycles of platinum based chemotherapy (93%) or a tyrosine kinase inhibitor (7%). We evaluate the change in serum CEA levels and the association with response measured by RECIST criteria. RESULTS: After two chemotherapy cycles, the patients who achieved an objective response (OR, 28.3%) had a reduction of CEA levels of 55.6% (95%CI [box drawings light horizontal]64.3 to [box drawings light horizontal]46.8) compared to its basal level, with an area under the ROC curve (AURC) of 0.945 (95%CI 0.91-0.99), and a sensitivity and specificity of 90.2 and 89.9%, respectively, for a CEA reduction of ≥14%. Patients that achieved a decrease in CEA levels ≥14% presented an overall response in 78% of cases, stable disease in 20.3% and progression in 1.7%, while patients that did not attain a reduction ≥14% had an overall response of 4.1%, stable disease of 63.6% and progression of 32.2% (p < 0.001). Patients with stable (49.4%) and progressive disease (22.2%) had an increase of CEA levels of 9.4% (95%CI 1.5-17.3) and 87.5% (95%CI 60.9-114) from baseline, respectively (p < 0.001). The AURC for progressive disease was 0.911 (95%CI 0.86-0.961), with sensitivity and specificity of 85 and 15%, respectively, for a CEA increase of ≥18%. PFS was longer in patients with a ≥14% reduction in CEA (8.7 vs. 5.1 months, p < 0.001). Neither reduction of CEA nor OR were predictive of OS. CONCLUSIONS: A CEA level reduction is a sensitive and specific marker of OR, as well as a sensitive indicator for progression to chemotherapy in patients with advanced NSCLC who had an elevated CEA at baseline and had received no more than one chemotherapy regimen. A 14% decrease in CEA levels is associated with a better PFS.