Feline Mammary Hypertrophy

Abstract

A retrospective study of some 500 biopsies from female cats showed 12 examples of a benign fibroglandular proliferation of the mammary gland. This condition has not been reported in the literature. The lesion resembles pericanalicular fibroadenoma of women and may involve one or more mammary glands in young, intact queens. No statistically significant breed incidence was found. The growths regress with ovariectomy, which suggests hormonal pathogenesis (hyperprogesteronism).

Hiperplasia fibroepitelial mamária em felinos: cinco casos

“…Macroscopicamente, todas as gatas apresentaram massas mamárias firmes com superfícies de corte brancacentas e multinodulares. Essas características têm sido descritas como típicas para a condição (ALLEN, 1973;JONES et al, 2000). No exame cuidadoso da superfície de corte, pode-se observar pontos mais claros que correspondem à proliferação ductal.…”

“…Esse parece não ser um procedimento indicado isoladamente pois a hiperplasia fibroepitelial nas gatas dos casos 3, 4 e 5 parece ter sido endógena, uma vez que não há histórico de uso de progestágenos. De modo geral, o tratamento para gatas afetadas por hiperplasia fibroepitelial mamária consiste na retirada do estímulo hormonal, seja endógeno ou exógeno, através de ovário-histerectomia ou suspensão do medicamento à base de progesterona, respectivamente (ALLEN, 1973). Quando a hiperplasia é acentuada e as mamas estão muito aumentadas, pode haver necessidade de extirpação cirúrgica.…”

Feline Mammary Fibroepithelial Hyperplasia: A Clinical Approach

“…It predominantly affects younger intact female cats, a segment of the population that also presents an increased ratio of spontaneous ovulation [15,16]. The reported age range for FEH is 6 months to 13 years [17][18][19][20]. Not so frequently, the condition may also be seen in aged females, associated or not with a contraceptive treatment, and sporadically in hormonally treated male tomcats.…”

“…It is possible that such response may be associated to two factors: the extreme sensitivity of the feline mammary gland to sex steroids action, as referred in older studies (Bässler, cited in [17]); and the fact that the mammary gland is usually very thin when non-pregnant or non-lactating [28].…”

“…Areas containing gelatinous material may be found, disposed as cleft-like spaces created by the enlarged ducts [21,37] (Figure 1). Although necrosis or ulceration are rare [17], they can be found in long lasting situations or whenever the reduction of the mammary gland swelling was attempted by progestin administration. Microscopically, the two patterns are similar [18]: the diseased mammary gland is characterized by the proliferation of glandular fibroepithelial elements.…”