Case Report
Neuroendocrine Cancer of Rectum Metastasizing to Ovary
Table 1
Compiled classification and nomenclatures of NENs.
|
Traditional nomenclature based on grades of differentiation and histopathology
| WHO; ENETs classification of NENs | Accepted nomenclature | Types | Mitotic index per 10 high power fields (HPF) | Immunohistochemistry Ki 67 index |
| Low | Carcinoid tumor | Neuroendocrine tumor (NET), grade 1 | <2 |
<3% | Well-differentiated neuroendocrine tumor (WD-NET) May be functional (F) or nonfunctional (NF) | Intermediate | Atypical carcinoid tumor | Neuroendocrine tumor (NET), grade 2 | 2–20 | 3–20% |
| High | Small-cell carcinoma Large-cell neuroendocrine carcinoma (NEC) | NEC grade 3, small-cell carcinoma NEC grade 3, large cell neuroendocrine carcinoma | >20 | >20% | High grade neuroendocrine carcinoma (HG-NEC) (F or NF) |
|
|