Can IASLC/ATS/ERS subtype help predict response to chemotherapy in small biopsies of advanced lung adenocarcinoma?

New International Association for the Study of Lung Cancer (IASLC) Pathology Committee Grading System for the Prognostic Outcome of Advanced Lung Adenocarcinoma

“…Although the clinical relevance of major histologic patterns in late-stage disease has been addressed, the specimens in these studies were mainly acquired by surgical resection or open biopsy [9,10]. Whether a small biopsy is representative of the actual predominant subtypes needs verification using a larger cohort [15]. Since most patients were diagnosed using small biopsy specimens in our study, a validation and correlation of grading between biopsies and resection is warranted.…”

“…Small biopsies remain the primary method for diagnosis, classification, and molecular analysis, accounting for 70% in advanced disease [13]. As the histologic subtype is an important predictive factor, core biopsy results are reliable representations of the original tumor entity and valuable for predicting prognosis [14][15][16][17][18]. In addition, it is vital to assess the relevance of driver gene mutations, such as the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), Kirsten rat sarcoma (KRAS), and proto-oncogene B-Raf (BRAF), in different subtypes when predicting a patient's prognosis [19][20][21][22].…”

Histological grading in lung cancer: one system for all or separate systems for each histological type?

“…However, a recent study in patients with advanced disease evaluated predominant subtype in core biopsies and classified tumours with papillary-, micropapillary-and solid-predominant patterns to be high grade. Patients with these high-grade patterns had better response rates to platinum-based therapy and progression-free survival than patients with lower grade adenocarcinomas [31,32]. Further validation is needed to demonstrate clinical relevance for grading in non-resection specimens.…”

Adenocarcinoma predominant pattern subtyping and nuclear grading in cytology: Is there a role in prognostication of advanced pulmonary adenocarcinomas?

“…Nevertheless, subtyping of non‐small cell lung carcinomas (NSCLC) into ADs and squamous cell carcinomas has been found to be accurate and definite on cytology and small biopsy specimens . Among ADs alone, one previous study showed that cytological features correlate with prognosis, while others found that pattern grading on small biopsies predicts response to chemotherapy . In addition, knowledge of the varied patterns of lung ADs and its recognition will aid in triage of material for molecular analysis …”

“…7,8 Among ADs alone, one previous study showed that cytological features correlate with prognosis, 9 while others found that pattern grading on small biopsies predicts response to chemotherapy. [10][11][12][13] In addition, knowledge of the varied patterns of lung ADs and its recognition will aid in triage of material for molecular analysis. [14][15][16] We aimed to predict architectural patterns and analyse nuclear grades of lung ADs on cytology, correlate their concordance with predominant pattern on paired small biopsies, and to assess outcome.…”