Small cell carcinoma of the lung and large cell neuroendocrine carcinoma interobserver variability

Abstract

Using non-preselected cases, the morphological WHO criteria for diagnosing SCLC and LCNEC leave room for subjective pathological interpretation, which results in imprecise categorization of SCLC and LCNEC cases.

What clinicians are asking pathologists when dealing with lung neuroendocrine neoplasms?

“…Accordingly, TC is deemed to be a low-grade malignant tumor with longer life expectation and time to recurrence, AC an intermediate-grade malignant tumor with more aggressive clinical course, somewhat unpredictable clinical behavior and shorter time to recurrence, and LCNEC and SCC high-grade malignant tumors with dismal prognosis, challenging therapy options and, often, difficulties in reliably distinguishing from each others, either pathologically, genetically or clinically 1,4,8,[14][15][16][17][18][19] .…”

“…Cytological criteria are then used to split SCC from LCNEC, although there is a considerable morphologic overlap between them making this separation quite subjective and difficult to carry out, with disappointingly low inter-observer diagnostic reproducibility 12,15,16,[22][23][24][25] .…”

Different micro-RNA expression profiles distinguish subtypes of neuroendocrine tumors of the lung: results of a profiling study

“…Currently, the 2004 World Health Organization classification of pulmonary neuroendocrine tumors is based on combined architectural patterns considering the two most relevant morphological parameters, that is, the mitotic index and the presence of necrosis, diagnosed by haematoxylin and eosin morphology. 3,8,9 However, these tumors represent a broad spectrum of phenotypically distinct entities, and the assignment of a given neuroendocrine lung tumor can occasionally be cumbersome even for experienced pathologists. 3,9,10 Thus, reproducible and objective (molecular) diagnostic criteria with clinical and prognostic value need to be established to achieve a more accurate assignment of the various types of pulmonary neuroendocrine tumors.…”

“…3,8,9 However, these tumors represent a broad spectrum of phenotypically distinct entities, and the assignment of a given neuroendocrine lung tumor can occasionally be cumbersome even for experienced pathologists. 3,9,10 Thus, reproducible and objective (molecular) diagnostic criteria with clinical and prognostic value need to be established to achieve a more accurate assignment of the various types of pulmonary neuroendocrine tumors. 3 Micro-RNA (miRNA) molecules are evolutionarily conserved, small RNA-molecules with a size of 19-24 nucleotides and, unlike mRNA, do not encode amino-acid sequences.…”

Factors Effecting Long-term Survival in Operated Large Cell Carcinoma of the Lung.

“…However, it became clear that the clinical and biological features of LCNEC are similar to those of small cell lung carcinoma (SCLC), and the differential diagnosis between LCNEC and SCLC is quite difficult in some cases. 8,9,10 11 Larger surgical specimens often yield more information, and the diagnosis often changes to adenocarcinoma or squamous cell carcinoma. It is difficult to distinguish a poorly differentiated squamous cell carcinoma or adenocarcinoma preoperatively because of the indefinite diagnosis criteria.…”