Invasive breast carcinoma - IARC

Occasionally, the colonic adenocarcinoma
is found several months to years after
resection of the ovarian metastases.
Rectal or sigmoid colon cancer accounts
for 75% of the metastatic colon tumours
to the ovary {1587,2605,3226}. The primary
tumour can also be located in the
pancreas, biliary tract or the appendix
{590,1848,2406,3199,3200}.
The Krukenberg tumour is almost always
secondary to a gastric carcinoma but
may occasionally originate in the intestine,
appendix, breast or other sites
{367,2605,3226}. Rarely, breast cancer
metastatic to the ovary presents clinically
as an ovarian mass. A much higher
percentage of cases of lobular carcinoma
of the breast, including those of
signet-ring cell type, metastasizes to the
o v a ry than does ductal carc i n o m a
{1142}. A wide variety of other tumours
may metastasize to the ovary.
Histopathology
The identification of surface implants,
multinodularity and intravascular tumour
emboli are extremely helpful histological
clues in the recognition of secondary
ovarian tumours that spread through the
abdominal cavity and tubal lumen. The
histological appearance of the metastases
is variable, depending on the
nature of the primary tumour.
Differential diagnosis
Sometimes, metastases resemble primary
ovarian tumours {2605,2980,3226}.
Metastatic colonic adenocarcinoma to
the ovary may be confused with primary
endometrioid or mucinous carc i n o m a
depending on whether the colonic carcinoma
is predominantly mucinous or nonmucinous.
Features that help to distinguish
colon cancer from endometrioid
c a rcinoma include luminal necro t i c
debris, focal segmental necrosis of the
glands, occasional presence of goblet
cells and the absence of müllerian features
(squamous differentiation, an adenofibromatous
component or association
with endometriosis). Also the nuclei lining
the glands of metastatic colon carcinoma
exhibit a higher degree of atypia than
those of endometrioid carcinoma.
Metastatic tumours may also closely
resemble primary mucinous ovarian
tumours. The former may be moderately
differentiated or so well differentiated that
they can be mistaken for mucinous borderline
or less often benign ovarian
Fig. 2.134 Metastatic lobular carcinoma of the
breast. Sectioned surface shows a solid, multinodular
tumour.
Fig. 2.135 Metastatic malignant melanoma. The
ovary is replaced by a multinodular nodular black
tumour.
tumours. Metastatic mucinous tumours to
the ovary can originate in the large intestine,
pancreas, biliary tract or the appendix.
Features supportive of the diagnosis
of a metastasis include bilaterality, histological
surface involvement by epithelial
cells (surface implants), irregular infiltrative
growth with desmoplasia, single cell
invasion, signet-ring cells, vascular invasion,
coexistence of benign-appearing
mucinous areas with foci showing a high
mitotic rate and nuclear hyperchromasia
and histological surface mucin {1614}.
Immunostains for cytokeratin 7 and 20
should be used with caution and along
with thorough consideration of all clinical
i n f o rmation keeping in mind that no
tumour shows absolute consistency in its
staining with these markers {2183}.
Krukenberg tumours must be distinguished
from primary and other metastatic
ovarian tumours including clear cell
adenocarcinoma, mucinous (goblet cell)
c a rcinoid and a variety of ovarian
tumours that contain signet-ring-like cells
filled with non-mucinous material.
Ovarian clear cell adenocarcinoma may
have a signet-ring cell component that
simulates a Krukenberg tumour; however,
the identification of a characteristic
tubulocystic pattern, hobnail cells, stromal
hyalinization and eosinophilic secretion
are helpful in establishing the diagnosis.
Mucinous carcinoid, either primary
or metastatic, may contain large areas of
signet-ring cells; however, teratomatous
elements other than carcinoid are usually
present in the former.
The tubular variant of Krukenberg
tumour, sometimes associated with stro-
Fig. 2.136 Metastatic renal cell carcinoma to the ovary. Note the tubules lined by cells with abundant clear
cytoplasm.
Secondary tumours of the ovary 195