Invasive breast carcinoma - IARC

Secondary tumours of the uterine
corpus
V. Abeler
U. Haller
Definition
Tumours of the uterine corpus that originate
from, but are discontinuous with, a
primary extrauterine tumour or a tumour
in the cervix or elsewhere in the uterus.
Clinical features
Signs and symptoms
The mean age of patients with extragenital
tumour metastasis to the uterus is 60
years. Patients have abnormal uterine
bleeding since most neoplasms metastatic
to the uterus infiltrate the endometrium
diffusely.
Imaging
Imaging studies are non-specific {1240,
1282,1576,3184}.
Macroscopy
Metastases may appear as solitary or
multiple tumours or be diffusely infiltrating.
Histopathology
The majority of metastases to the uterus
a re confined to the myometrium.
However, approximately one-third involve
the endometrium and thus can be
detected in biopsy specimens {1529}.
Metastatic carcinoma within the
endometrium and/or myometrium characteristically
infiltrates as single cells,
cord or glands. The appearance is particularly
striking in lobular carcinoma of
the breast, which usually retains its single-file
pattern, and with metastatic
signet-ring cell carcinoma of the stomach
or colon. Metastatic colon carcinoma
of the usual type may form large tumour
masses and can mimic an endometrial
carcinoma of mucinous or endometrioid
type.
Metastatic carcinoma in the endometrium
should be suspected if one or more
of the following features are pre s e n t
{1539}.
(1) A tumour with an unusual macroscopic
or histological pattern for primary
endometrial carcinoma.
(2) Diffuse replacement by tumour of
endometrial stroma with sparing of occasional
normal endometrial glands.
(3) Lack of premalignant changes in
endometrial glands.
(4) Lack of tumour necrosis
For specific identification of certain prim
a ry tumours immunohistochemical
studies are frequently required.
Origin and histogenesis
In most instances the primary tumour is
well known, or disseminated disease is
clinical evident. Occasionally, a tumour
diagnosed by curettage or hysterectomy
represents the first sign of an extrauterine
primary tumour.
Secondary tumours of the uterine corpus
can be divided into two major groups:
tumours of the genital and extragenital
organs. Neoplasms of neighbouring
organs such as cervix, fallopian tubes,
ovaries, bladder and rectum can metastasize
to the uterine corpus via lymphatics
or blood vessels but mostly represent
local direct extension.
Haematogenous or lymphatic uterine
metastases from any extragenital primary
tumour may occur but are extremely
rare. Reported primary tumours
include carcinomas of the breast, stomach,
colon, pancreas, gallbladder, lung,
u r i n a ry bladder and thyroid and
melanoma {192,1452,1455,1529,1531,
1620,1720}. Mammary lobular carcinoma,
gastric signet-ring cell carcinoma
and colonic carcinoma are the most frequently
re p o rted extragenital primary
tumours {1529,1531}.
Prognosis and predictive factors
When uterine metastases are present,
the patient usually has widely disseminated
disease. However, in one series
the average survival was 20 months after
the diagnosis of uterine metastases. The
reason for this relatively favourable outcome
might be the predominance of
cases of metastatic breast carcinoma
{1529}.
A
Fig. 4.59 Metastatic colon carcinoma to the myometrium. A Note the tumour cells in lymphatic vessels in the
right upper portion of the field with a plexiform pattern on the left. B The neoplastic glands are positive for cytokeratin
20.
B
Fig. 4.60 Metastatic melanoma to the endometrium.
Tumour cells containing melanin pigment surround
an atrophic endometrial gland.
Secondary tumours of the uterine corpus 257