Prognostic Significance of Defining L-Cell Type on the Biologic Behavior of Rectal Neuroendocrine Tumors in Relation with Pathological Parameters

• Published in: Cancer research and treatment Vol. 47; no. 4; pp. 813 - 822
• Main Authors: Sohn, Jin Hee, Cho, Mee-Yon, Park, Yangsoon, Kim, Hyunki, Kim, Woo Ho, Kim, Joon Mee, Jung, Eun Sun, Kim, Kyoung-Mee, Lee, Jae Hyuk, Chan, Hee Kyung, Park, Do Youn, Joo, Mee, Kim, Sujin, Moon, Woo Sung, Kang, Mi Seon, Jin, So-Young, Kang, Yun Kyung, Yoon, Sun Och, Han, HyeSeung, Choi, EunHee
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Cancer Association 01.10.2015; 대한암학회
• Subjects: Biomarkers, Tumor; Female; Humans; Immunohistochemistry; Immunophenotyping - methods; Lymph Nodes - pathology; Male; Middle Aged; Neoplasm Grading; Neuroendocrine Tumors - classification; Neuroendocrine Tumors - pathology; Original; Rectal Neoplasms - classification; Rectal Neoplasms - pathology; Republic of Korea; Survival Analysis; 의약학; Immunohistochemistry; International Classification of Diseases; L cells; Rectal neoplasms; Survival; Neuroendocrine tumors
• ISSN: 1598-2998; 2005-9256; 2005-9256
• DOI: 10.4143/crt.2014.238

In 2010, the World Health Organization categorized L-cell type neuroendocrine tumors (NETs) as tumors of uncertain malignancy, while all others were classified as malignant. However, the diagnostic necessity of L-cell immunophenotyping is unclear, as are tumor stage and grade that may guide diagnosis and management. To clarify the predictive markers of rectal neuroendocrine neoplasms (NENs), 5- and 10-year overall survival (OS) was analyzed by pathological parameters including L-cell phenotype. A total of 2,385 rectal NENs were analyzed from our previous multicenter study and a subset of 170 rectal NENs was immunophenotyped. In univariate survival analysis, tumor grade (p < 0.0001), extent (p < 0.0001), size (p < 0.0001), lymph node metastasis (p=0.0063), and L-cell phenotype (p < 0.0001) showed significant correlation with the prognosis of rectal NENs; however, none of these markers achieved independent significance in multivariate analysis. The 10-year OS of tumors of NET grade 1, < 10 mm, the mucosa/submucosa was 97.58%, 99.47%, and 99.03%, respectively. L-Cell marker, glucagon II (GLP-1&2), with a cut off score of > 10, is useful in defining L-Cell type. In this study, an L-cell immunophenotype was found in 83.5% of all rectal NENs and most, but not all L-cell type tumors were NET G1, small (< 10 mm) and confined to the mucosa/submucosa. From these results, the biological behavior of rectal NENs does not appear to be determined by L-cell type alone but instead by a combination of pathological parameters.