Histological comparison between preoperative and surgical specimens of non-small cell lung cancer for distinguishing between "squamous" and "non-squamous" cell carcinoma

Abstract

BackgroundNon-small cell lung cancers (NSCLCs) are frequently heterogeneous and in approximately 70% of cases, NSCLCs are diagnosed and staged by small biopsies or cytology rather than by examination of surgically resected specimens. Thus, in most patients, the diagnosis is established based on examination of preoperative specimens alone. Recently, classification of NSCLC into pathologic subtypes has been shown to be important for selecting the appropriate systemic therapy, from both the point of view of treatment efficacy and prevention of toxicity.MethodsWe retrospectively reviewed the data of 225 patients to compare the preoperative classification of the NSCLC subtype on biopsy specimens with the postoperative classification based on examination of the resected specimens, in order to compare the accuracy of the two for the diagnosis of various histological subtypes of NSCLC.ResultsIn 169 of the 225 (75.1%) patients, the preoperative diagnosis was definite malignancy. Histologically, the final pathologic diagnosis made from the surgical specimens was adenocarcinoma (ADC) in 169 patients, and in 75.5% of these cases, the diagnosis was concordant with the preoperative diagnosis. Among the patients who had squamous cell carcinoma (SQC) in the preoperative specimens, the diagnosis was concordant with the preoperative diagnosis in 65.7% of cases. Misclassified preoperative biopsies included an even number of SQCs and ADCs, with all the misclassified biopsies being ADCs morphologically mimicking SQC due to solid growth. Significantly higher specificity, negative predictive value and accuracy were observed for the diagnosis of SQC.ConclusionsOur study suggested that the concordance rates for diagnosis of the NSCLC subtypes, especially the "squamous" or "non-squamous" histologies, between preoperative and surgical specimens were satisfactory, as compared with previous reports. Therefore, pretreatment diagnosis of lung cancer using small samples is reasonable for selecting the optimal treatment. However, in order not to lose the opportunity for selecting an effective treatment, we should be aware that the diagnosis in preoperative small samples might be different from that based on examination of the surgical specimens.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2032698427120488

Cytomorphology is often insufficient to categorize non‐small‐cell lung carcinoma on FNA specimens

“…Yamagishi et al showed that H + E cores without stains had 94% accuracy for SCC and 79% accuracy for ADC with respect to the final resection diagnosis. In cases where immunostains were added, there was 97% and 91% accuracy for SCC and ADC, respectively . How does this impact our results is difficult to gauge.…”

“…Pairwise kappa scores ranged from −0.16 to 0.47. The raters differed ( χ (12) = 104, p < 0.001) in the frequency with which they used intermediate categories (Table ). For example, rater 1 (0%) never used intermediate categories, whereas rater 2 (76%) frequently used the intermediate categories.…”

“…Lung cancer remains the leading cause of cancer mortality worldwide . Historically, this disease is divided into small‐cell lung carcinoma and non‐small‐cell lung carcinoma (NSCLC), with the latter accounting for approximately 80–85% of primary lung cancers . Patient management now differs between the subtypes of NSCLC, specifically squamous cell carcinoma (SCC) and adenocarcinoma (ADC).…”

“…Patient management now differs between the subtypes of NSCLC, specifically squamous cell carcinoma (SCC) and adenocarcinoma (ADC). For example, ADC histology predicts improved outcome following treatment with the combination of pemetrexed and cisplastin . ADCs also have a greater likelihood of harboring mutations in the epidermal growth factor receptor ( EGFR) gene and respond better to EGFR tyrosine kinase inhibitors.…”

Serum protein profiles of patients with lung cancer of different histological types

“…12 However, accurately subtyping lung cancers histologically and molecularly before treatment is not always achievable primarily due to limited availability of tissue samples. 13 On the other hand, liquid biomarkers such as serum carcinoembryonic antigen (CEA), cytokeratin-19 fragments (CYFR-211) and neuron-specific enolase (NSE) may assist in differentiating the diagnosis, but their specificity and practical values remain to be further evaluated. 14 Characteristic protein profiles determined by proteomic approaches have been increasingly investigated as biomarkers of diagnosis, prognosis and responses to treatment in cancer patients.…”