Invasive breast carcinoma - IARC

the ovary and bladder. Unlike primary
endometrial tumours, those metastatic to
the endometrium are pure transitional cell
tumours. The CK7 positive, CK20 negative
immunoprofile also supports müllerian
rather than urothelial diff e re n t i a t i o n .
Somatic genetics
Human papillomavirus (HPV) type 16 has
been detected in 22% of cases studied;
however, the results were negative for
types 6, 11, 18, 31 and 33 in all cases
assessed {1554,1672}. These findings
suggest that HPV may play an aetiologic
role in at least some cases.
Prognostic and predictive factors
Although information on prognostic factors
is limited on these rare tumours, several
women who have survived have had
low stage (stage I) disease. At least two
cases with extrauterine extension of the
disease to either the adnexa or ovarian
hilus have survived over 5 years following
radiation therapy suggesting that these
tumours may have a more favourable
response to radiation therapy than other
stage II endometrial carc i n o m a s .
Fig. 4.12 Squamous cell carcinoma of the endometrium. This invasive tumour forms well differentiated
squamous pearls. Note the reactive stroma with inflammatory cells.
Small cell carcinoma
Definition
An endometrial carcinoma resembling
small cell carcinoma of the lung.
Epidemiology
Small cell carcinoma of neuroendocrine
type is an uncommon tumour of the
endometrium that comprises less than
1% of all carcinomas.
Fig. 4.13 Transitional cell carcinoma. The neoplasm forms papillae lined by low grade stratified transitional type
epithelium.
Histopathology
The histological appearance is similar to
that of small cell carcinoma in other
organs. Small cell carcinomas are positive
for cytokeratin and mostly positive for
neuroendocrine markers, whereas onehalf
are positive for vimentin.
Prognosis and predictive factors
In contrast to small cell carcinoma elsewhere
in the female genital tract, the
prognosis is far better in stage I disease
with a 5-year survival of about 60% {23,
1271}.
Undifferentiated carcinoma
Undifferentiated carcinomas are those
lacking any evidence of differentiation.
Fig. 4.14
ratios.
Small cell carcinoma. The tumour is composed of small cells with high nuclear to cytoplasmic
Epithelial tumours and related lesions 227