Clinical significance of the ‘not otherwise specified’ subtype in candidates for resectable non-small cell lung cancer

Abstract

The histological subtype of non-small-cell lung cancer (NSCLC) is a significant factor when selecting treatment strategies. However, cases are occasionally encountered that are diagnosed as ‘not otherwise specified’ (NOS) prior to surgery, due to an uncertain histological subtype. The present study investigated the prognostic significance of the NOS subtype for patients with resectable NSCLC. Between 2001 and 2011, 1,913 patients were diagnosed with NSCLC using transbronchial biopsy and underwent surgical resection at two facilities in Japan. Of these patients, 151 (7.9%) were pre-operatively diagnosed with NSCLC-NOS (NOS group) and the remainder had confirmed histological subtypes (confirmed group). The present study compared the clinicopathological features and prognoses of these groups. Analyses of resected specimens revealed that pleomorphic cell carcinoma, large cell neuroendocrine cell carcinoma, large cell carcinoma and adenosquamous carcinoma were significantly more common in the NOS group than in the confirmed group (P<0.001, P=0.002, P=0.019 and P=0.014, respectively). The five-year survival rate was significantly poorer in the NOS group (60.5 vs. 67.1%; P=0.010), particularly for stage I disease (70.8 vs. 80.7%; P=0.007). The results of a multivariate analysis of overall survival indicated that NOS was a significant independent prognostic factor (hazard ratio, 1.40; 95% confidence interval, 1.02–1.86; P=0.041). These results indicated that pre-operative NOS was significantly associated with poorer survival, including for stage I disease. In conjunction with other clinicopathological parameters, NOS can be a useful prognostic factor when deciding on a treatment strategy for NSCLC.

Lung cancer prognostic index: a risk score to predict overall survival after the diagnosis of non-small-cell lung cancer

“…Pursuit of tissue for mutation testing is encouraged in older patients and those presenting with poor PS, particularly where linked to lung cancer burden, with adverse survival outcomes for patients not tested vs negative for mutation attributed to these factors in multivariate analyses. Conversely, patient factors did not explain the adverse prognosis of patients with NSCLC NOS in our study, a finding supported by other studies ( Righi et al , 2014 ; Tane et al , 2014 ).…”

Patterns of Extrathoracic Metastasis in Lung Cancer Patients

“…The NSCLC, NOS group showed the highest metastasis rate (52.1%), which was higher even than that of the SCLC group (51.7%). This result is consistent with those of several previous studies, which suggested that the diagnosis of NSCLC, NOS is a poor prognostic factor on its own [ 19 , 20 ]. However, this should be interpreted with caution.…”

Trends, and tumor characteristics of lung cancer and malignant pleural mesothelioma in the East of Libya

“…[28] Moreover, the NOS subtype of NSCLC represented 12.6% of reported pathology in our study, which was relatively high in comparison to SEERS data, in which NOS represented 2.9% of NSCLC subtypes. [29] It is crucial to identify the subtype of NSCLC histopathology as it predicts the prognosis and directs the type of therapy for each subtype. For example, anti-EGFR tyrosine kinase Inhibitors and anti-ALK therapy are working with AC, and anti-angiogenesis therapy is associated with bleeding in squamous pathology.…”