il tumore della prostata. ii. stadiazione

Università degli Studi di Pavia
AA 2010 - 2011
Corso Integrato di Clinica Medica
Insegnamento di Oncologia Medica
IL TUMORE DELLA PROSTATA. II.
STADIAZIONE
Prof. Alberto Riccardi
STAGING METHODS
PROSTATIC CANCER
Clinical staging. I.
* TNM staging system includes categories for
cancers palpable on DRE, those identified solely on
basis of abnormal PSA (T1c), those palpable but
clinically confined to gland (T2) and those extended
outside gland (T3 and T4)
PROSTATIC CANCER
Clinical staging. II.
* DRE alone inaccurate in assessing extent of
disease within gland, capsular invasion, involvement
of seminal vescicles and spread to nodal or more
distant sites;
* assessment refined by imaging studies
[ultrasound, computed tomoghraphy (CT), magnetic
resonance imaging (MRI) and bone scan];
- however, no single test accurately predicts
pathologic stage (organ - confined disease? seminal
vesical involvement? lymph node spread?)
PROSTATIC CANCER
Clinical staging. III. Transrectal ultrasound
* transrectal
ultrasound (TRUS)
most frequently used
→ no consistent
finding predicts PC
with certainty →
primarly used to direct
prostate biopsy
PROSTATIC CANCER
Clinical staging. IV. CT scan
* CT scans lack
sensitivity and
specificity for
extraprostatic
extension and
inferior to MRI in
visualization of
lymph nodes
* CT scan can show abnormal lymph nodes in pelvis
and abdomen, but not sensitive enough to identify
microscopic cancer cells in lymph nodes = CT scans do
not provide reliable enough information about condition
of prostate or stage of prostate cancer
PROSTATIC CANCER
Clinical staging. V. MRI
* MRI (still lacking sensitivity and specificity) ↑ lymph
node detection, especially of endorectal coil;
[- T1 - weighted images: periprostatic fat and venous
plexus, perivesicular tissues, lymph nodes, and bone
marrow;
- T2 - weighted images: internal architecture of prostate
and seminal vesicles (low signal in most cancers, high
signal in normal peripheral zone)];
- MRI also useful for planning of surgery and radiation
therapy
= neither TC nor MRI accurately predicts pathologic
stage at surgery
PROSTATIC CANCER
Clinical staging. VI. Radionuclide bone scanning
* to evaluate spread to osseous
sites;
- sensitive but relatively non
specific (areas of ↑uptake from
osteoblastic activity secondary to
metastases or other condition,
including healing fractures,
arthritis and Paget's disease);
* true+ bone scan rare if PSA < 8
and uncommon if PSA < 10 ng /
mL (unless high grade tumor)
= when PSA < 10 ng / mL, false+
scan common → additional low yield testing, including CT and MRI
PROSTATIC CANCER
Clinical staging. VII.
Molecular diagnostic (experimental)
* seeks to identify presence of
circulating PC cells using an
assay for PSA based on reverse
transcriptase - polymerase
chain reaction (RT - PCR) in
leukocyte fraction of peripheral
blood or bone marrow;
- test+ in large % of pts with
tumors seemingly confined to
organ (unclear significance)
STAGING
STAGING
* two schemes commonly used to stage PC;
- TNM stage system: most common (by
American Joint Committee on Cancer, AJCC),
evaluating size of tumor, extent of involved
lymph nodes, metastasis and cancer grade;
- Whitmore - Jewett stage: now used less
commonly for research, but often still used by
clinicians
TNM STAGING
PROSTATIC CANCER
TNM clinical staging
* T categories:
* clinically inapparent, not palpable tumor (T1a
- T1b) or detected from ↑ serum PSA (T1c);
* palpable but clinically confined to gland (T2),
and:
* extended outside gland (T3 and T4);
* N categories: presence or absence of nodal
metastases;
* M categories: presence or absence of distant
metastases
PROSTATIC CANCER
TNM clinical staging
PROSTATIC CANCER
Clinical staging
TNM definitions: T1
* TX: primary tumor cannot be assessed;
* T0: no evidence of primary tumor;
* T1: clinically inapparent tumor not palpable nor
visible by imaging:
T1a: incidental histologic finding in ≤ 5% of tissue
resected;
T1b: incidental histologic finding in > 5% of tissue
resected;
T1c: identified by needle biopsy due to elevated PSA
PROSTATIC CANCER
Clinical staging
TNM definitions: T2
* T2: confined within prostate:
- T2a: involving 1 lobe;
- T2b: involving both lobes;
[- note: tumor found in 1 or both lobes by needle
biopsy, but not palpable or visible by imaging,
classified as T1c]
PROSTATIC CANCER
Clinical staging
TNM definitions: T3 - T4
* T3: tumor extends through prostatic capsule:
T3a: extracapsular extension (uni- or bilateral);
T3b: tumor invades seminal vesicle(s);
[- note: invasion into prostatic apex or into (but not
beyond) prostatic capsule is not classified as T3, but as
T2];
* T4: tumor fixed to or invading adjacent
structures other than seminal vesicles (bladder
neck, external sphincter, rectum, levator muscles
and / or pelvic wall)
LOCAL
STAGING
OF
PROSTATE
CANCER
PROSTATIC CANCER
Clinical staging. TNM definitions: Regional nodes (N)
* = nodes of true pelvis (= nodes below
bifurcation of common iliac arteries, including
pelvic, hypogastric, obturator, iliac, periprostatic,
and sacral);
* distant lymph nodes = outside confines of true
pelvis (aortic, common iliac, inguinal, superficial
inguinal, supraclavicular, cervical, scalene, and
retroperitoneal nodes) and their involvement =
distant metastases;
* NX: regional lymph nodes cannot be assessed;
* N0: no regional lymph node metastasis;
* N1: metastasis in regional lymph node(s)
[- note: laterality does not affect N classification]
PROSTATIC CANCER
Clinical staging. TNM definitions
Distant metastasis (M)
* MX: distant metastasis cannot be assessed;
* M0: no distant metastasis;
* M1: distant metastasis;
M1a: nonregional lymph node(s);
M1b: bone(s);
M1c: other site(s)
PROSTATIC CANCER
Clinical staging: limits. I.
* limit of TNM system = most PC are now
diagnosed as T1c (by needle biopsy, often
because ↑ PSA) or T2 (still confined within
prostate) disease, leading to attempts at refining
prediction of local disease extent:
- multiplex staging models (based on a
combination of findings of digital examination,
biopsy, Gleason score and baseline PSA);
- models based on no. of cores and % of each
core involved by tumor;
* unproven efficacy at predicting node
involvement
PROSTATIC CANCER
Variables in multiplex staging models
PROSTATIC CANCER
Clinical staging. Differentiation (G)
PROSTATIC CANCER
AJCC stage groupings
Stage I
T1a, N0, M0, G1
Stage III
T3, N0, M0, any G
Stage II
T1a, N0, M0, G 2, 3 - 4
T1b, N0, M0, any G
T1c, N0, M0, any G
T2, N0, M0, any G
Stage IV
T4, N0, M0, any G
any T, N1, M0, any G
any T, any N, M1, any G
PROSTATIC CANCER
AJCC stage groupings
STAGING
WHITEMORE - JEWETT STAGING
PROSTATIC CANCER
Whitemore - Jewett Staging System. Stage A
* stage A = clinically undetectable tumor
confined to prostate gland, as incidental
finding at prostatic surgery;
- substage A1: G1 with focal involvement, usually
left untreated;
- substage A2: G2 - G3 or involving multiple foci
in gland
Multicentricity of prostate cancer
whole mount section of prostate showing two distinct foci of
adenocarcinoma illustrating the frequent finding of multicentricity
PROSTATIC CANCER
Whitemore - Jewett Staging System. Stages B - C
* stage B = confined to prostate gland:
substage B0: nonpalpable, PSA - detected;
substage B1: single nodule in 1 lobe;
substage B2: more extensive involvement of 1 lobe or
involvement of both lobes
* stage C = clinically localized to periprostatic area
but extending through prostatic capsule, with
seminal vesicles possibly involved:
substage C1: clinical extracapsular extension;
substage C2: extracapsular tumor producing bladder
outlet or ureteral obstruction
PROSTATIC CANCER
Whitemore - Jewett Staging System. Stage D
* Stage D = metastatic disease:
substage D0: clinically localized disease (prostate
only) but persistently elevated enzymatic serum
acid phosphatase titers;
substage D1: regional lymph nodes only;
substage D2: metastases to distant lymph nodes,
bone or visceral organs;
substage D3: D2 prostate cancer pts who
relapsed after adequate endocrine therapy
STAGING
COMPARISON BETWEEN TNM AND
WHITEMORE - JEWETT STAGING
CLINICAL STAGES
BY TNM CLASSIFICATION
AND
WHITMORE - JEWETT
STAGING SYSTEM