When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy
The dualistic classification of epithelial ovarian cancer (EOC) into “type I” and “type II” is widely applied in the research setting; it is used as a convenient way of conceptualizing different mechanisms of tumorigenesis. However, this classification conflicts with recent molecular insights of the...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2018-12-01
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| Series: | Frontiers in Oncology |
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| Online Access: | https://www.frontiersin.org/article/10.3389/fonc.2018.00654/full |
| _version_ | 1818574412691013632 |
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| author | Carolina Salazar Carolina Salazar Ian G. Campbell Ian G. Campbell Kylie L. Gorringe Kylie L. Gorringe |
| author_facet | Carolina Salazar Carolina Salazar Ian G. Campbell Ian G. Campbell Kylie L. Gorringe Kylie L. Gorringe |
| author_sort | Carolina Salazar |
| collection | DOAJ |
| description | The dualistic classification of epithelial ovarian cancer (EOC) into “type I” and “type II” is widely applied in the research setting; it is used as a convenient way of conceptualizing different mechanisms of tumorigenesis. However, this classification conflicts with recent molecular insights of the etiology of EOC. Molecular and cell of origin studies indicate that while type II tumors could be classed together, type I tumors are not homogenous, even within the histological types, and can have poor clinical outcomes. Type II high grade serous carcinoma and type I low grade serous carcinomas best fit the description of the dualistic model, with different precursors, and distinct molecular profiles. However, endometriosis-associated cancers should be considered a separate group, without assuming an indolent course or type I genetic profiles. Furthermore, the very clear differences between mucinous ovarian carcinomas and other type I tumors, including an uncertain origin, and heterogeneous mutational spectrum and clinical behavior, indicate a non-type I classification for this entity. The impression that only type II carcinomas are aggressive, have poor prognosis, and carry TP53 mutations is an unhelpful misinterpretation of the dualistic classification. In this review, we revisit the history of EOC classification, and discuss the misunderstanding of the dualistic model by comparing the clinical and molecular heterogeneity of EOC types. We also emphasize that all EOC research, both basic and clinical, should consider the subtypes as different diseases beyond the type I/type II model, and base novel therapies on the molecular characteristics of each tumor. |
| first_indexed | 2024-12-15T00:26:19Z |
| format | Article |
| id | doaj.art-f21b8c71586544d98db1c21dd04ba8b6 |
| institution | Directory Open Access Journal |
| issn | 2234-943X |
| language | English |
| last_indexed | 2024-12-15T00:26:19Z |
| publishDate | 2018-12-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Oncology |
| spelling | doaj.art-f21b8c71586544d98db1c21dd04ba8b62022-12-21T22:42:09ZengFrontiers Media S.A.Frontiers in Oncology2234-943X2018-12-01810.3389/fonc.2018.00654429907When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated DichotomyCarolina Salazar0Carolina Salazar1Ian G. Campbell2Ian G. Campbell3Kylie L. Gorringe4Kylie L. Gorringe5Peter MacCallum Cancer Centre, Melbourne, VIC, AustraliaSir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, AustraliaPeter MacCallum Cancer Centre, Melbourne, VIC, AustraliaSir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, AustraliaPeter MacCallum Cancer Centre, Melbourne, VIC, AustraliaSir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, AustraliaThe dualistic classification of epithelial ovarian cancer (EOC) into “type I” and “type II” is widely applied in the research setting; it is used as a convenient way of conceptualizing different mechanisms of tumorigenesis. However, this classification conflicts with recent molecular insights of the etiology of EOC. Molecular and cell of origin studies indicate that while type II tumors could be classed together, type I tumors are not homogenous, even within the histological types, and can have poor clinical outcomes. Type II high grade serous carcinoma and type I low grade serous carcinomas best fit the description of the dualistic model, with different precursors, and distinct molecular profiles. However, endometriosis-associated cancers should be considered a separate group, without assuming an indolent course or type I genetic profiles. Furthermore, the very clear differences between mucinous ovarian carcinomas and other type I tumors, including an uncertain origin, and heterogeneous mutational spectrum and clinical behavior, indicate a non-type I classification for this entity. The impression that only type II carcinomas are aggressive, have poor prognosis, and carry TP53 mutations is an unhelpful misinterpretation of the dualistic classification. In this review, we revisit the history of EOC classification, and discuss the misunderstanding of the dualistic model by comparing the clinical and molecular heterogeneity of EOC types. We also emphasize that all EOC research, both basic and clinical, should consider the subtypes as different diseases beyond the type I/type II model, and base novel therapies on the molecular characteristics of each tumor.https://www.frontiersin.org/article/10.3389/fonc.2018.00654/fullepithelial ovarian cancertype I-II tumorsdualistic modelclassificationovarian carcinoma |
| spellingShingle | Carolina Salazar Carolina Salazar Ian G. Campbell Ian G. Campbell Kylie L. Gorringe Kylie L. Gorringe When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy Frontiers in Oncology epithelial ovarian cancer type I-II tumors dualistic model classification ovarian carcinoma |
| title | When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy |
| title_full | When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy |
| title_fullStr | When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy |
| title_full_unstemmed | When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy |
| title_short | When Is “Type I” Ovarian Cancer Not “Type I”? Indications of an Out-Dated Dichotomy |
| title_sort | when is type i ovarian cancer not type i indications of an out dated dichotomy |
| topic | epithelial ovarian cancer type I-II tumors dualistic model classification ovarian carcinoma |
| url | https://www.frontiersin.org/article/10.3389/fonc.2018.00654/full |
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