Invasive lobular breast carcinoma presenting hepatic carcinomatosis: A case report

Abstract

Metastatic carcinomatosis to the liver is a pattern of malignant infiltration that tends to provoke liver fibrosis. It is a
rare complication of multiple types of solid tumors and often seen in the absence of a discrete tumor mass in the liver.
We report the case of a patient who presented the rare diagnosis of metastatic carcinomatosis for liver from breast cancer. A woman at the age of 42 years presented invasive lobular carcinoma, pT3 pN0 M0, positive immunohistochemistry
70% for estrogen receptor and 30% progesterone, HER2 and E-cadherin negative, and Ki67 of 5%. The patient during the
fourth year of adjuvant hormone therapy with tamoxifen presented an increase in serum tumor marker (CA 125: 17–130),
with no evidence of systemic disease on imaging tests. Due to the slightly cirrhotic contour of the liver on a computed
tomography, a liver biopsy was performed for investigation. The early diagnosis of occult and diffuse dissemination to the
liver was made by means of a percutaneous liver biopsy showing invasive breast cancer cells, with immunohistochemistry compatible with metastasis of lobular breast carcinoma, positive for hormone receptors, and doubtful for HER-2, with
KI67 of 20%. Metastatic carcinomatosis, unlike lesions of discrete liver masses, may not be detectable with imaging tests,
and often biopsy or autopsy is needed to confirm the diagnosis. This case highlights a rare and difficult to early diagnosis
pattern of hepatic carcinomatosis due to lobular breast carcinoma.