Prostate Cancer – Major Changes in the American Joint Committee on Cancer Eighth Edition Cancer Staging Manual

Abstract

The eighth edition of the American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) Staging Manual has been updated and improved to ensure the highest degree of clinical relevance and to improve its utility for patient evaluation and clinical research. Major changes include: 1) pathologically organconfined disease is now considered pT2 and is no longer subclassified by extent of involvement or laterality, 2) tumor grading now includes both the Gleason score (as in the seventh edition criteria) and the grade group (introduced in the eighth edition criteria), 3) prognostic stage group III includes select, organ-confined disease based on prostate-specific antigen and Gleason/grade group status, and 4) 2 statistical prediction models are included in the staging manual. The AJCC will continue to critically analyze emerging prostate cancer biomarkers and tools for their ability to prognosticate and guide treatment decision making with the highest level of accuracy and confidence for patients and physicians.

Introduction

The American Joint Committee on Cancer (AJCC) has been working closely with all of its member organizations throughout the development of the recently published eighth edition Cancer Staging Manual. The coordination of the implementation for a new staging system is critically important to ensure that all partners in patient care and cancer data collection are working in synchrony.

To ensure that the cancer care community has the necessary infrastructure in place for documenting eighth edition stage, the AJCC Executive Committee, in dialogue with the National Cancer Institute Surveillance, Epidemiology, and End Results program; the Centers for Disease Control and Prevention; the College of American Pathologists; the National Comprehensive Cancer Network; the National Cancer Data Base; and the Commission on Cancer, made the decision to delay implementation of the eighth edition cancer staging system to January 1, 2018.

Clinicians will continue to use the latest information for patient care, including scientific content of the eighth edition manual. All newly diagnosed cases through December 31, 2017 should be staged with the seventh edition. The time extension will allow all partners to develop and update protocols and guidelines and for software vendors to develop, test, and deploy their products in time for the data collection and implementation of the eighth edition in 2018.

Prostate Cancer

The AJCC published the first edition of the Cancer Staging Manual in 1977. Staging is important to: 1) categorize the severity of disease, 2) estimate prognosis, 3) recommend treatment, and 4) aid health care providers and researchers in exchanging information about patients. The AJCC methodology uses the T (tumor extent), N (lymph node invasion), and M (presence or absence of metastasis) classifications to group patients. The TNM staging, used in combination with tumor grade and prostate-specific antigen (PSA), is regarded as a well accepted practice standard for prostate cancer and is used as the basis for guiding treatment decision making.

According to the American Cancer Society, approximately 161,360 new cases of prostate cancer will be diagnosed, and 26,730 men will die of this disease during 2017.¹ The vast majority of prostate cancer, approximately 95%, presents clinically localized to the prostate without definite evidence of metastasis (ie, cN0M0). As a consequence, the initial clinical assessment of the primary tumor has been based on digital rectal examination (DRE) findings and histologic confirmation of prostate cancer. Prostate cancer screening with serum levels of PSA, a protein produced by cells of the prostate gland, yields the majority of patients who are diagnosed annually, as the majority present with nonpalpable disease. As a result, many patients with newly diagnosed prostate cancer present with nonpalpable disease and are classified in the cT1c-category. To further enhance the value of clinical staging, the AJCC introduced the addition of pretreatment serum PSA and tumor grade to TNM classification in the seventh edition of the manual to create prognostic stage groups. This major change improved the prognostic value of the AJCC system, enhanced its clinical relevance, and continues in the eighth edition.

Summary of Major Changes Between the Seventh and Eighth Editions

Table 1 lists the major changes between the seventh and eighth editions of the manual. The first major change to the staging involves the pathologic subclassification of organ-confined disease. In the seventh edition, a 3-tier system was used to subdivide pathologic T2 disease (pT2) based on the extent and laterality of disease: pT2a, unilateral and confined to less than one-half of a lobe of the prostate; pT2b, unilateral involving more than one-half of a lobe of the prostate; and pT2c, bilateral involvement. However, several recent studies have failed to demonstrate the prognostic value of this distinction.² Without clear evidence of clinical relevance for a 3-tier system, the current eighth edition defines a single pT2 category, eliminating the subcategories, for all organ-confined disease.

TABLE 1.

Summary of Changes Between the Seventh and Eighth Editions

CHANGE	DETAILS OF CHANGE
Definition of primary tumor (T)	Pathologically organ-confined disease is considered pT2 and no longer subclassified by extent of involvement or laterality.
Histologic grade (G)	The Gleason score (seventh edition criteria) and the grade group (eighth edition criteria) should both be reported.
AJCC prognostic stage groups	Stage III includes select, organ-confined disease based on prostate-specific antigen and Gleason/grade group status.
Statistical prediction models	Those statistical prediction models that satisfy all necessary criteria are included in the staging manual.

Abbreviation: AJCC indicates American Joint Committee on Cancer.

The second major change involves incorporation of a new histopathologic classification of tumors. A new histologic grading system is used. The histologic grade of prostate cancer is an important factor, if not the most important, for the prognosis of clinically localized prostate cancer. For over 40 years, the Gleason system has been the most commonly accepted practice standard for prostate cancer grading. The Gleason system scores the primary and secondary patterns of cancer from 1 to 5, and the Gleason score is the sum of the 2 patterns (eg, 3 + 3 = 6). In recent years, the World Health Organization and the International Society for Urologic Pathology formalized changes to the Gleason system and the adoption grade groups for prostate cancer based on published data from several thousand prostate cancers treated surgically and by radiation therapy. The grade groups are now numbered from 1 to 5, where grade group 1 is similar to ≤3 + 3 = 6 tumors, grade group 2 is similar to 3 + 4 = 7 tumors, grade group 3 is similar to 4 + 3 = 7 tumors; grade group 4 is similar to Gleason sum 8 tumors, and grade group 5 is similar to Gleason sum 9 and 10 tumors.^2,3 The current eighth edition uses group grade given its superior prognostic value.

The third major change is a revision to the prognostic stage grouping, in which stage III will now include select, organ-confined disease based on PSA and Gleason/grade group status, albeit with minor modifications to be more consistent with risk categorizations used in clinical treatment guidelines, such as those of the National Comprehensive Cancer Network and the American Urological Association.

An interesting observation from a global staging principle perspective is that, with the inclusion of nonanatomic factors in prostate cancer (grade groups and serum PSA), the prognostic stage group III includes some organ-confined prostate cancers. This is in contrast to stage groupings in most other cancers, where AJCC prognostic stage group III is invariably associated with nonorgan-confined disease. However, there is precedence for the stage III designation of organ-confined disease in other solid tumor types that takes into account the established impact of tumor grade (eg, mitotic rate in gastrointestinal stromal tumor) and location/multifocality (eg, hepatocellular carcinoma).

As the fourth major change, the eighth edition has adopted a strategy to include statistical prediction models for select cancers. Over time, more cancers will be evaluated; and, when satisfactory statistical prediction models are identified, they will be provided and continually updated on the AJCC Web site (cancerstaging.org). Prostate cancer risk-assessment models, along with models for lung cancer, breast cancer, melanoma, head and neck cancer, and soft tissue sarcoma, were evaluated by the Precision Medicine Core for the eighth edition of the AJCC Staging Manual. Evaluations were based and recommendations were made only if models met stringent inclusionary and exclusionary criteria proposed by the Precision Medicine Core,⁴ which performed a systematic search of published literature for prognostic models in prostate cancer from January 2011 to December 2015. Fifteen prognostic models in prostate cancer were identified, but only 2 of the 15 models met all predefined AJCC inclusion and exclusion criteria and are endorsed by the AJCC.^5,6 Both of these models were based on data from large phase 3 trials in the setting of castrate-resistant, metastatic disease and were externally validated (see Table 2).^5,6 In the localized prostate cancer models, the primary reason for exclusion of all 9 was the use of an outcome other than overall survival. Although another endpoint in the localized disease setting may be appropriate, the present AJCC guidelines focus on the use of overall survival as the outcome of interest.

TABLE 2.

Prognostic Models for Prostate Cancer

APPROVED PROGNOSTIC TOOL	WEB ADDRESS	FACTORS INCLUDED IN THE MODEL
Metastatic castration-resistant prostate cancer (Halabi 20146)	cancer.duke.edu/Nomogram/firstlinechemotherapy.html	ECOG performance status, site of metastases, PSA, hemoglobin, albumin, alkaline phosphatase, LDH > 1 ULN, opioid analgesic use
Metastatic castration-resistant prostate cancer treated with second-line chemotherapy(Halabi 20135)	cancer.duke.edu/Nomogram/secondlinechemotherapy.html	ECOG performance status, visceral disease, progression on docetaxel, duration on hormone, measurable disease, pain, PSA, hemoglobin, alkaline phosphatase

Abbreviations: ECOG indicates Eastern Cooperative Oncology Group; LDH, lactate dehydrogenase; PSA, prostate-specific antigen; ULN, upper limit of normal.

Pathological Considerations

Histologic examination of prostatic adenocarcinoma, most commonly in a radical prostatectomy specimen, is required for pathologic TNM stage classification. The major change to pathologic evaluation in the eighth edition is the elimination of pT2 substaging, a decision based on both the problems with practical application of laterality determination by pathologists and data on the relative prognostic predictive value of cancer volume versus pT2 substage. Pathologists were often faced with delineation of an arbitrary midline for determining bilaterality of prostate cancer. Because of this, by past criteria, a very small posterior tumor that crossed the midline would be classified as higher stage than a much larger tumor that was confined to one side.⁷ Even more importantly, emerging data strongly suggest that a true volume measurement is more prognostically important than pT2 substage.^8–10 pT3 substaging remains the same as in the seventh edition, but pathologists were provided with more guidance as to the histologic definition of “extraprostatic” tissue in various anatomic regions. It is also suggested that a method for the quantification of extraprostatic extension be used, such as the classification as “focal” or “established (nonfocal).”¹¹ pN and pM category assignment is also unchanged.

In the eighth edition, it is recommended that both the Gleason grade and the grade group should be used to determine tumor grade. Although the group grade system is unique and not directly relatable to Gleason score, the 2 can be generally related as follows: grade group 1 (≤ Gleason score 6), grade group 2 (Gleason score 3 + 4 = 7), grade group 3 (Gleason score 4 + 3 = 7), grade group 4 (Gleason score 4 + 4 = 8, 3 + 5 = 8, 5 + 3 = 8), and grade group 5 (Gleason score 9–10). This grade group system has several notable advantages. First, in modern pathologic grading, Gleason score 6 (3 + 3) is the lowest grade reported, although the scale historically was from 2 to 10. A system that now begins with grade group 1 more accurately and more clearly reflects the lowest grade and the biologically least aggressive cancers, perhaps assisting patients and providers as they consider observational strategies such as active surveillance. Second, Gleason sum 7 is clearly not homogeneous in morphology or biologic behavior, in that 3 + 4 = 7 (grade group 2) has a much better prognosis than 4 + 3 = 7 (grade group 3); now, there is division among the Gleason sum 7 cancers that may have implications in treatment strategies, in particular with patients who pursue radiation therapy. Finally, Gleason 8 to 10 tumors were often considered as one category of high-grade disease; however, evidence also indicates that Gleason score 8 (grade group 4) tumors should be separated from Gleason 9 and 10 (grade group 5) tumors based on substantially different prognostic value. The grade group system is now supported by validation in multiple cohorts.^12–15

Finally, there is a continued recommendation for consistent processing and reporting of standard pathologic parameters in prostate cancer according to the College of American Pathologists’ prostate protocols.¹⁶ Specifically, the importance of reporting margin status and histologic subtype is emphasized.

Radiologic Considerations

Imaging tests can provide useful staging information in prostate cancer. For clinical T categorization (cT), the most valuable modality is magnetic resonance imaging (MRI) using high-resolution T2 images. This method provides the most accurate demarcation of the extent of the primary tumor. Although MRI provides the best information among all imaging methods regarding extraprostatic extension, it has proven insufficiently sensitive to justify routine use in all but higher risk tumors.^17,18 MRI has proven more useful in evaluating for seminal vesicle invasion), and MRI-guided biopsies can be obtained to confirm the presence of seminal vesicle invasion.^17,18

For N categorization, computed tomography (CT) or MRI images of the pelvis are often obtained. However, nodal staging with CT or MRI notoriously underestimates the extent of nodal involvement because involved lymph nodes are often smaller than the 0.8 to 1 cm short axis size criteria for positivity.¹⁹ Thus, in high-risk cancers, CT or MRI may be more useful in identifying enlarged lymph nodes because of a higher positive predictive value; whereas, for intermediate-risk tumors in which the positive lymph nodes are smaller, the positive predictive value is lower.

For M categorization, technetium-99m bone scanning continues to be a well accepted standard imaging method given the propensity of prostate cancer to form osteoblastic metastases in the bone. More recently, sodium fluoride (NaF) positron emission tomography (PET)-CT has been introduced as a more sensitive method of detecting prostate cancer bone metastases; however, there is also lower specificity (a higher risk of false-positive results). This test is most useful when the conventional bone scan is negative but the clinical suspicion of bone metastases is high. For instance, in men with high-risk tumors who have negative conventional imaging, the NaF PET-CT may reveal metastases, thus modifying patient management. Confirmation of NaF-imaged lesions by MRI is advised when the bone scan and CT are negative and there is no other explanation for the uptake (eg, trauma, degenerative disease). Otherwise, in most cases, a bone scan is sufficient for detecting bone metastases, and the increased sensitivity of NaF PET-CT is not needed.²⁰ For the detection of visceral metastases, conventional CT and MRI have proven satisfactory, although it is rare for visceral manifestations to present at initial staging.

TNM Evaluation

T

Prostate cancer does not occur uniformly throughout the prostate. Although cancers of the prostate often are multifocal, from 80% to 85% arise from the peripheral zone, 10% to 15% arise from the transition zone, and 5% to 10% arise from the central zone. The peripheral zone is located posteriorly, abutting the rectum, and is amenable to DRE and biopsy by transrectal ultrasound (TRUS) guidance. The transition zone comprises the anteromedial prostate and is not routinely sampled with a systematic TRUS-guided biopsy. Patients who have suspected cancer involving the anterior prostate, such as those with a negative TRUS biopsy and persistently rising PSA, may be good candidates for a saturation biopsy or MRI-guided biopsy. The central zone comprises part of the base of the prostate and the area surrounding the ejaculatory ducts and is seldom the source of cancer but often is invaded by the extension of larger cancers arising in the peripheral zone.

N

The regional lymph nodes are the nodes of the true pelvis, which essentially are the pelvic lymph nodes below the bifurcation of the common iliac arteries. They include the following groups: pelvic, hypogastric, obturator, iliac, and sacral (lateral, presacral, or promontory [ie, Gerota]).

M

Distant lymph nodes lie outside the confines of the true pelvis. The distant lymph nodes include the following: aortic, common iliac, deep inguinal, superficial inguinal (ie, femoral), supraclavicular, cervical, scalene, and retroperitoneal. Bones are the most common nonnodal sites of prostate cancer metastasis; these lesions are usually osteoblastic rather than osteolytic. Lung and liver metastases usually are identified late in the course of the disease.

Classification

Table 3 shows the definitions for clinical and pathological T, N, and M classifications.

TABLE 3.

Definitions of American Joint Committee on Cancer TNM Criteria

CATEGORY	CRITERIA
Clinical (cT)
T category
TX	Primary tumor cannot be assessed
T0	No evidence of primary tumor
T1	Clinically inapparent tumor that is not palpable
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 found in one or both sides, but not palpable
T2	Tumor is palpable and confined within prostate
T2a	Tumor involves one-half of one side or less
T2b	Tumor involves more than one-half of one side but not both sides
T2c	Tumor involves both sides
T3	Extraprostatic tumor that is not fixed or does not invade adjacent structures
T3a	Extraprostatic extension (unilateral or bilateral)
T3b	Tumor invades seminal vesicle(s)
T4	Tumor is fixed or invades adjacent structures other than seminal vesicles, such as external sphincter, rectum, bladder, levator muscles, and/or pelvic wall
Pathologic (pT)
T category
T2	Organ confined
T3	Extraprostatic extension
T3a	Extraprostatic extension (unilateral or bilateral) or microscopic invasion of bladder neck
T3b	Tumor invades seminal vesicle(s)
T4	Tumor is fixed or invades adjacent structures other than seminal vesicles, such as external sphincter, rectum, bladder, levator muscles, and/or pelvic wall
N category
NX	Regional lymph nodes were not assessed
N0	No positive regional lymph nodes
N1	Metastases in regional lymph node(s)
M category	M criteria
M0	No distant metastasis
M1	Distant metastasis
M1a	Nonregional lymph node(s)
M1b	Bone(s)
M1c	Other site(s) with or without bone disease

Clinical

In healthy men suspected of having prostate cancer because of either an abnormal DRE or an elevated PSA test, a transrectal needle biopsy of the prostate gland usually is performed, with ultrasound guidance, to obtain histologic confirmation of prostate carcinoma. Much less commonly, prostate cancer may be diagnosed because of a transurethral resection of prostate performed to relieve obstructive symptoms.

Assigning the clinical T category (cT) is accomplished using information from the DRE of the prostate and should always reflect DRE findings only. Masses of the peripheral zone may feel like distinct and solid nodularity. Deeper lesions may require firm palpation to detect and also can be associated with glandular asymmetry and/or induration. Signs of extraprostatic extension on DRE include an irregular, gritty texture of the overlying capsule or flattening of the lateral sulcus. Apical extraprostatic extension can be subtler. The seminal vesicles may not always be palpable, but extension into the seminal vesicle can be palpated as a firm protrusion from the prostate at the base associated with a large mass. Imaging, such as ultrasound or MRI, and biopsy information, such as the laterality of involvement or estimates of tumor volume, are not recommended for T categorization. To be recommended in clinical staging, evaluations will need to be universally accessible and well standardized to avoid stage migration without an associated change in prognostication.

Enlarged lymph nodes can occasionally be observed on CT or MRI; however, fewer patients are initially discovered with clinically evident metastatic disease. In patients with small, low-grade tumors, imaging tests to detect metastatic disease have not been proven to be helpful and are not recommended.

The histologic grade of the prostate cancer is important for prognosis. It is recommended that both the Gleason score and the grade group be reported together. The serum PSA level completes the clinical assessment and, together with TNM and group grade, an AJCC prognostic stage group (see Table 4) can be defined.

TABLE 4.

American Joint Committee on Cancer Prognostic Stage Grouping^a

WHEN T IS…	AND N IS…	AND M IS…	AND PSA IS…	AND GRADE GROUP IS…	THEN THE STAGE GROUP IS…
cT1a-c, cT2a	N0	M0	<10 ng/mL	1	I
pT2	N0	M0	<10 ng/mL	1	I
cT1a-c, cT2a	N0	M0	≥10, <20 ng/mL	1	IIA
pT2	N0	M0	≥10, <20 ng/mL	1	IIA
cT2b-c	N0	M0	<20 ng/mL	1	IIA
T1-2	N0	M0	<20 ng/mL	2	IIB
T1-2	N0	M0	<20 ng/mL	3	IIC
T1-2	N0	M0	<20 ng/mL	4	IIC
T1-2	N0	M0	≥20 ng/mL	1–4	IIIA
T3-4	N0	M0	Any	1–4	IIIB
Any T	N0	M0	Any	5	IIIC
Any T	N1	M0	Any	Any	IVA
Any T	Any	M1	Any	Any	IVB

Abbreviation: PSA indicates prostate-specific antigen.

^aNote that, when either PSA or grade group is not available, grouping should be determined by T category and/or either PSA or grade group, as available.

Pathological

Assigning the pathological T (pT) category is accomplished in radical prostatectomy specimens. The basic boundary of the prostate is a condensed fibromuscular layer of prostatic stroma, the “capsule,” that is best recognized in posterior and posterolateral aspects of the gland, but not in the apex, anterior, or bladder neck regions. Even in regions with a well defined capsule, tumor-related or biopsy-related fibrous change may cause difficulty in the evaluation of extraprostatic extension. Microscopic bladder neck invasion (ie, tumor detected in bladder neck/proximal margin sections) is classified as pT3a.

Pelvic lymph node dissection is the standard means for staging (pN) lymph node metastasis in prostate cancer.

Common Clinical Questions

A common question involving the clinical cT category is: What is the most appropriate category for a tumor that is found in one or both lobes by needle biopsy, but is not palpable or visible by imaging? It is important to remember that there is no laterality specification for cT1 tumors; and, regardless of side or bilateral involvement, this situation is classified as cT1c.

Another common question is: What is the appropriate cN category if a patient does not have imaging? Consider a patient with a PSA of 8 ng/mL and group grade 1 disease who is found to have cT2a disease, in which the risk of lymph node involvement is very low. The physician may use judgment to assign cN0 based on the low probability of nodal involvement without imaging to assign it. If the risk of nodal involvement is high and imaging is not performed, then cNX would be appropriate.

The most appropriate pathological staging for patients who do not undergo radical prostatectomy is another common question. Without undergoing a prostatectomy or additional biopsy procedures, there is insufficient tissue to assess the pathological stage, and a pathological stage should not be assigned. The pT, pN, pM and pathologic stage groups are not completed. If however, a biopsy is performed and confirms a regional lymph node metastasis, then a pN1 category can be assigned, and the pathological stage is cT pN1 cM stage IVA. Similarly, if the patient has biopsy-proven distant metastasis, then pM1 is used, and the pathological stage is assigned as cT cN pM1 stage IVB.

Another common question involves the assignment of pN category when no lymph nodes are removed with the prostatectomy. The assignment is pNX if no lymph nodes are removed with the prostatectomy. The pT is assigned, then pNX, and the cM is assigned, but the stage group is unknown and cannot be assigned.

The diagnosis of a positive apical surgical margin commonly raises a question. If fat is not present in the apical section, but tumor is present at the surgical margins, then the appropriate staging would be pT2.²¹ Some uropathology experts designate such cases as pT3, the rationale being that, if the urologist has gone as far wide and distal as possible and only malignant glands are seen at the margins, then the tumor should be considered extraprostatic. Rarely, fat may be present at the apex of the prostatectomy specimen, and the presence of tumor in adipose tissue at this site indicates pT3 disease.²²

Areas for Further Research

There are several promising imaging methods on the horizon that may improve the staging of prostate cancer in the near future. Prime among these is the prostate-specific membrane antigen (PSMA) PET-CT. A series of high-affinity gallium-68–labeled and fluorine-18 (F-18)–labeled ligands have been developed that bind PSMA, an antigen expressed in prostate cancers and their metastases.²³ Thus, PSMA PET-CT is a promising method for both lymph node and bony staging. Other agents in the same category include F-18 choline and anti-1-amino-3-[18F]fluorocyclobutane-1-carboxylic acid (F-18-FACBC), both of which target prostate cancer, although they do not appear to be as sensitive in head-to-head trials as PSMA PET-CT.²⁴ However, because none of these are yet widely available, they cannot be recommended as part of the current standard of care. Similarly, progress has been made in imaging lymph nodes with ultrasmall particles of iron oxide combined with MRI, as normal lymph nodes will take up the agent and turn dark, but abnormal lymph nodes will not.²⁵ However, this technique, termed magnetic resonance lymphography, although able to depict lymph nodes outside of the normal surgical template, is also still investigational.²⁵

The primary utility for more sensitive imaging is for patients considering local therapy, such as surgery or radiation; for those patients at high risk of failing local therapy modalities, such as those with high-risk, localized disease, who are seeking primary treatment; or for those seeking salvage therapies. Under these circumstances, the need for better imaging of metastatic disease is most acute.

It is notable that many of the patients imaged with the newer technologies are diagnosed with oligometastatic disease. Although exact definitions of oligometastatic are variable, it conceptually represents an intermediate step between localized disease and widespread metastases.²⁶ It is hypothesized that these patients with oligometastatic disease may benefit from local therapy.²⁷ It is further hypothesized that eradication of all sites of oligometastatic disease could result in clinical benefits.²⁸ Trials to investigate these hypotheses in prostate cancer are ongoing.

Conclusions

The eighth edition of the AJCC TMN Staging Manual has been updated and improved to ensure the highest degree of clinical relevance. It no longer subcategorizes pT2 and now includes grade group, in addition to retaining the prognostic value of serum PSA and grade group in staging. The AJCC will continue to critically analyze emerging prostate cancer biomarkers and tools for their ability to prognosticate and guide treatment decision making with the highest level of accuracy and confidence for patients and physicians.

Practical Implications for Continuing Education.

• This paper presents a detailed summary of the 8th Edition of the American Joint Commission on Cancer (AJCC) tumor-node-metastasis (TNM) staging for prostate cancer that will be implemented on January 1, 2018.

• One major change in the 8th edition is the recommended use of a new prostate cancer grading system endorsed by the International Society of Urologic Pathology (ISUP) that may require additional skills for clinical staff.

• This summary is aimed to help with education efforts within the cancer care community to ensure that infrastructure is in place for documenting the 8th Edition stage.