Cardiac tumors of mice

Area of Science:

• Veterinary Pathology
• Oncology
• Experimental Pathology

Background:

• Primary cardiac tumors in mice are rare, with only three previously reported.
• The Registry of Experimental Cancers provided access to seven primary mouse heart tumors for this study.

Purpose of the Study:

• To characterize the types and origins of primary and metastatic tumors affecting the mouse heart.
• To investigate the potential link between ionizing radiation and the development of primary cardiac neoplasms.

Main Methods:

• Histopathological examination of seven primary mouse heart tumors.
• Analysis of tumor origin for twelve metastatic heart tumors.
• Correlation of tumor incidence with prior ionizing radiation exposure in mice.

Main Results:

• Seven primary heart tumors included three mesenchymal cell sarcomas, three hemangioendotheliomas, and one mesenchymoma.
• Mesenchymal cell sarcomas demonstrated hematogenous metastasis to lungs, kidneys, and spleen.
• Five primary tumors occurred in mice exposed to ionizing radiation.
• Three mice presented with cardiac tumors as part of multifocal neoplasms, including reticulum cell sarcomas.

Conclusions:

• This research expands the known spectrum of primary mouse heart tumors.
• Ionizing radiation may be a contributing factor in the development of primary cardiac tumors in mice.
• Metastatic tumors to the heart originate from various primary sites, notably the lung and subcutaneous tissues.