Consent for publication

No patient recruitment or communication was needed for this study. No identifiable patient information or image was included. For this type of study, consent for publication is not required.

Competing interests

The authors declare no competing interests.

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

This is a retrospective study and only existing pathology slides and images were utilized. For this type of study, informed consent is not required.