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Prostate Cancer Treatment Information

TNM Definitions
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Primary tumor (T)

TX: Primary tumor cannot be assessed
T0: No evidence of primary tumor
T1: Clinically inapparent tumor not palpable nor visible by imaging

T1a: Tumor incidental histologic finding in 5% or less of tissue resected

T1b: Tumor incidental histologic finding in more than 5% of tissue resected

T1c: Tumor identified by needle biopsy (e.g., because of elevated PSA)

T2: Tumor confined within prostate*

T2a: Tumor involves 1 lobe
T2b: Tumor involves both lobes

T3: Tumor extends through the prostatic capsule**

T3a: Extracapsular extension (unilateral or bilateral)
T3b: Tumor invades seminal vesicle(s)

T4: Tumor is fixed or invades adjacent structures other than seminal

vesicles: bladder neck, external sphincter, rectum, levator muscles, and/or pelvic wall

*Note: Tumor found in 1 or both lobes by needle biopsy, but not palpable or reliably visible by imaging, is classified as T1c.
**Note: Invasion into the prostatic apex or into (but not beyond) the prostatic capsule is not classified as T3, but as T2.

Regional lymph nodes (N)

Regional lymph nodes are the nodes of the true pelvis, which essentially are the pelvic nodes below the bifurcation of the common iliac arteries. They include the following groups (laterality does not affect the N
classification): pelvic (NOS), hypogastric, obturator, iliac (internal,
external, NOS), periprostatic, and sacral (lateral, presacral, promontory
(Gerota's), or NOS). Distant lymph nodes are outside the confines of the true pelvis and their involvement constitutes distant metastasis. They can be imaged using ultrasound, computed tomography, magnetic resonance imaging, or lymphangiography, and include: aortic (para-aortic, periaortic, lumbar), common iliac, inguinal, superficial inguinal (femoral), supraclavicular, cervical, scalene, and retroperitoneal (NOS) nodes.

NX: Regional lymph nodes cannot be assessed
N0: No regional lymph node metastasis
N1: Metastasis in regional lymph node or nodes

Abbreviation: NOS, not otherwise specified.

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)

***Note: When more than 1 site of metastasis is present, the most advanced category (pM1c) is used.

Histopathologic grade (G)

GX: Grade cannot be assessed
G1: Well differentiated (slight anaplasia)
G2: Moderately differentiated (moderate anaplasia)
G3-4: Poorly differentiated or undifferentiated (marked anaplasia)

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