Eble JN, Sauter G., Epstein JI, Sesterhenn IA - iarc

A
Fig. 3.39 A Gleason score 3+3=6. B Gleason pattern 3 with small glands.
B
associated with as adverse prognosis as
a Gleason score 4+5=9 {2005}. When
this tertiary pattern is pattern 4 or 5, it
should be reported in addition to the
Gleason score, even when it is less than
5% of the tumour.
Although comparable data do not currently
exist for needle biopsy material, in
the setting of three grades on biopsy
where the highest grade is the least common,
the highest grade is incorporated
as the secondary pattern. An alternative
option is in the situation with a tertiary
high grade pattern (i.e. 3+4+5 or 4+3+5)
is to diagnose the case as Gleason score
A
8 with patterns 3, 4 and 5 also present.
The assumption is that a small focus of
high grade cancer on biopsy will correlate
with a significant amount of high
grade cancer in the prostate such that
the case overall should be considered
high grade, and that sampling artefact
accounts for its limited nature on biopsy.
Reporting Gleason scores in cases with
multiple positive biopsies
In cases where different positive cores
have divergent Gleason scores, it is controversial
whether to assign an averaged
(composite) Gleason score or whether
the highest Gleason score should be
considered as the patient’s grade {1407}.
In practice, most clinicians take the highest
Gleason score when planning treatment
options.
Grading of variants of prostate cancer
Several morphological variants of prostate
adenocarcinoma have been described
(e.g. mucinous and ductal cancer). They
are almost always combined with conventional
prostate cancer and their effect on
prognosis is difficult to estimate. In cases
with a minor component of a prostate cancer
variant, Gleason grading should be
based on the conventional prostate cancer
present in the specimen. In the rare
case where the variant form represents
the major component, it is controversial
whether to assign a Gleason grade.
Grading of specimens with artefacts
and treatment effect
Crush artefacts. Crush artefacts are common
at the margins of prostatectomy
specimens and in core biopsies. Crush
artefacts cause disruption of the glandular
units and consequently may lead to overgrading
of prostate cancer. These artefacts
are recognized by the presence of
noncohesive epithelial cells with fragmented
cytoplasm and dark, pyknotic nuclei
adjacent to preserved cells. Crushed
areas should not be Gleason graded.
Hormonal and radiation treatment.
Prostate cancer showing either hormonal
or radiation effects can appear artefactu-
B
Fig. 3.40 A Cribriform Gleason score 3+3=6. B
Prostate cancer Gleason pattern 3 of cribriform
type.
Fig. 3.41 Gleason pattern 3 prostatic adenocarcinoma
with amphophilic to cleared cytoplasm.
Fig. 3.42 Gleason score 4+4=8.
182 Tumours of the prostate