PERSPECTIVE AND PATTERNS OF SPREAD
The TNM staging system of the male genitourinary tract (MGU) depends on whether the organ oncoanatomy is solid and encapsulated or hollow and tubular.
PERSPECTIVE AND PATTERNS OF SPREAD
The urinary tract of kidney, renal pelvis and ureter, urinary bladder, and urethra can frequently be involved with carcino-genesis owing to the excretion of toxic antigenic products or proteins, which can be harmful and transform their epithelial lining. Carcinogenic field effects, cancer in situ, and seeding o the excretory urinary system are major concerns; instead of a single tumor, there can be multiple cancers. Of interest, patterns of spread are limited often to the urinary system; however, juxtaposed structures are at risk (Fig. 34.1; Table 34.1AB). Prostate cancer, which is the dominant malignancy in males, particularly among those >50 years of age, is included with cancers of the MGU. With each decade of age it increases in incidence, affecting every other male in his 80s. In contrast, testicular cancer is the most common tumor in younger males (30–50 years). Prostate and testicular cancers are among the most highly curable tumors owing to both early diagnosis and advances in multimodal treatment.
Tests for male genital cancers were among the first to incorporate the leading-edge advances in molecular bio-marker prognosticators. The development of serum prostate-specific antigen (PSA) into a universal serum screening test has completely changed prostate cancer from a clinically palpable tumefaction to a nonpalpable early-stage disease for which histologic confirmation by needle biopsy is necessary t establish its existence (i.e., T1c). Serum PSA is a powerful prognosticator and is the most useful clinical biomarker for prostate cancer, which includes its rate of increase or doubling time. In testicular tumors, several serum markers exist, namely alpha fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase. Staging of testicular cancers is unique because it involves the first durable instance of bio marker inclusion in the TNM staging system (Table 34.1). Furthermore, these molecular markers are useful in determining “cure” or control of the cancer and are often the first evidence of relapse if they are found to be elevated in follow-up visits.
Applying the SIMLAP concept to each organ in the MGU allows for understanding the anatomic interrelationships and is presented here using prostate cancer as an illustration. The prostate gland occupies a similar position to that of the cervix in the female pelvis. The prostate gland is at the anatomic isocenter in the male pelvis:
• Superior is the urinary bladder.
• Inferior is the bulb of the penis.
• Medial is the urethra.
• Lateral is the pelvic sidewall, acetebulum, and femoral head.
• Anterior is the pubic bone.
• Posterior is the rectum.
The six vectors of invasion are superior, inferior, medial, lateral, anterior, and posterior. The color -coded dots in the respective SIMLAP tables correlate the T stage with the specific anatomic structure involved
Figure 34.1| Patterns of spread. The cancer at each primary site is presented at the different anatomic locations of the MGU, color-coded as to stage: T0, Tis, Ta, yellow; T1, green; T2, blue; T3, purple; T4, red. The primary sites shown are from superior to inferior: the urinary bladder, the prostate, the penis, and the testes.
TNM STAGING CRITERIA
CLASSIFICATION AND STAGING
TNM Staging Criteria
Pathology in terms of Gleason grade was added to the TNM anatomic criteria in the sixth edition of the American Joint Committee on Cancer's AJCC Cancer Staging Manual, and the PSA has been added in the seventh edition. Both bound and free PSA levels are useful. Thus, both the PSA and Gleason grade pathology have been incorporated into the staging system, extending criteria beyond anatomic factors.
The oncoanatomy paradigm of solid versus hollow organs is a dichotomy in organ anatomic architecture that applies to the male genitourinary system.
The staging system is based on the pattern of spread, which depends on whether the organ oncoanatomy is solid and encapsulated or hollow and tubular. With solid organs, tumor growth within the capsule has a good prognosis; however, once the capsule is breeched or penetrated, the likelihood of a successful outcome decreases (Fig. 34.2). The solid organs are kidney, prostate, and testes. Urinary tract cancers of the renal pelvis, ureters, and bladder follow the classification and staging of thin-walled, hollow organs lined with transitional epithelium over their musculature. That is, the depth of penetration of the layers in their wall determines the T stage (Fig. 34.2). The adoption of the alphabetical American Urological Association classification into the TNM language has allowe for unification of the literature. The poorly differentiated variety of cancers, especially in solid organs, can result in widespread lymphatic and hematogenous metastases. Virtually every remote and distant site can be involved. Kidney cancer has a predilection for lung, as do most testicular cancers, but bone and brain are often sites for dissemination.
An especially unique metastatic pattern is the predilection of prostate cancer to form axial vertebral metastases. The extensive osteoblastic sclerosis of bone is virtually pathognomonic when pelvis, lumbar, and thoracic vertebral bodies appear uniformly positive first on bone scans and then as white, dens bones in radiographs. This has been attributed to retrograde venous spread of prostate cancer cells from the periprostatic plexus of veins to Batson's vertebral venous plexus.
SUMMARY OF CHANGES SEVENTH EDITION AJCC
The classification of solid organs, the kidne, prostate, and testes depends on whether the tumor is confined (T1T2) or invasio through their adventitial fibrous capsule (T3) and into surround ing adjacent structures or fixation to bone (T4) has occurred (Fig. 34.2). The renal pelvis and ureter are staged similar to the bladder, and their cancers follow the same pattern for staging hollow viscera as in the digestive system: T1, mucosal; T2, submucosal muscle layer; T3, fibrous outer wall or peritoneum; an T4, invasion into adjacent tissues. The T stage determines the stage group. The N1 and M1 are considered stage IV.
The Stage Summary Matrix for Renal Cell Cancer indicates the general rule for most MGU Cancer Sites. That is, the T category determines the Stage Group whereas Testis is unique and perhaps a vision of the future in staging cancers in that serum markers are the dominant factor where the TNM paradigm is simplified. The cancer progresses in T stage then N and followed by M for Stage Group I– >II–>III respectively (Table 34.1C and Table 34.1D).
Figure 34.2 | TNM staging systems. T stage only. A. Kidney represents a solid organ. B. Renal pelvis represents a hollow organ. C. Urinary bladder represents a hollow organ. D. Prostate represents a solid organ. The T category determines the stage. Color-coded with bars: stage T0, yellow; I, green; II, blue; III, purple; and IV, red.
OVERVIEW OF THE HISTOGENESIS IN THE MALE GENITOURINARY SYSTEM
The urinary system consists of two kidneys, each with a renal pelvis that drains into two separate ureters, which enter the urinary bladder with its single urethral exit. The male genital system consists of the prostate, seminal vesicles, the testes, and the penis (Fig. 34.3). The cancer histopathology relates to the epithelium of the different sections (Fig. 34.3; Table 34.2).
• The majority of renal cancers arise in epithelium of the proximal or distal convoluted tubule. The functional unit of each kidney is the convoluted tubule, which consists of a nephron and a collecting duct (Fig. 34.3B).
• Cancers of the renal pelvis arise in the excretory portion of the urinary system, which is lined with a transitional epithelium covering a multilayered wall consisting of a submucosa, a circular and longitudinal muscle layer, and most often a fibrous adventitia or a serosa-like external coverin (Fig. 34.3C).
• In the bladder, the epithelium is transitional when empty but flattened, almost squamous-like, when full and distended. Most cancers are transitional cell (Fig. 34.3C), although squamous cell cancers and adenocarcinomas can and do occur in the bladder.
• Cancers of the penis and urethra tend to be squamous cell cancers arising from stratified squamous cell mucosal linin and skin (Fig. 34.3D).
• Cancers of the prostate arise from tubuloalveolar glandular epithelium and transit into adenocarcinomas of varying grade (Fig. 34.3E).
• Cancers of the testes are highly varied owing to the testes unique genetic and gonadal function (Fig. 34.3F).
The separation of two juxtaposed abdominal and pelvic cavity systems is by a single layer of mesothelial cells. The peritoneum is sufficient to protect the genitourinary system fro invasion by gastrointestinal cancers and vice versa. MGU cancers tend to spread within their system involving or complicating their function. Seeding of ureters and bladder with renal pelvis cancer is a common concern. MGU tumors never seed out into the peritoneal cavity, in contrast with gastrointestinal tract (GIT) cancers, which may. Except for the kidney and ureters, the rest of the genitourinary system is confined to th true pelvis. The two anatomic sectors are intraperitoneal and retroperitoneal.
Figure 34.3 | Overview of histogenesis. A. The cancer originates in the various histogenic phenotypes of epithelial cells of MGU organs. B. Renal. C. Renal pelvis, ureter, and bladder. D. Penis and urethra. E. Prostate. F.Special gonadal testis.
T-ONCOANATOMY
ORIENTATION OF T-ONCOANATOMY: ODYSSEY OF PRIMARY SITES
The anatomic isocenters of the seven primary sites in the male genitourinary system are presented in multiplanar orientation diagrams (Fig. 34.4A,B). Each of the primary sites is presented in three planes—coronal, sagittal, and axial—as well as their sentinel and regional lymph nodes and adjacent organs.
The odyssey of the seven MGU primary sites is presented from cephalad to caudad (Table 34.3). The tabulation aligns each primary site with associated surrounding structures and osseous landmarks when feasible. The sentinel node for each primary site is also noted. The MGU tract includes highly vascular organs, placing them at high risk for hematogenous dissemination.
The MGU are in the true pelvis in juxtaposition to the alimentary system. The orientation three-dimensional/three-planar diagram is presented from cephalad to caudad, with the kidney ranging from T12 to L3, the ureters from L3 to S4, and the urinary bladder from S3 to S5. The prostate is at the coccyx, and the penis and testes are outside the bony pelvis and are perineal structures.
In the orientation of pelvic organs it is important to view the osseous anatomy (Fig. 34.5A), the cavities in the musculoskeletal anatomy (Fig. 34.5B), and the different anatomic sectors that house the viscera and neurovasculature (Fig. 34.5C). The bony pelvis above the pelvic brim is referred to as the greater or false pelvis because it houses and contains the contents of the peritoneal cavity. The true pelvis on coronal section is below the pelvic brim, shaped like a wine glass, and houses the male and female genital organs and the urinary bladder. The floor o the true pelvis is the levator ani muscle covered with superior and inferior parietal fascia, and its roof is the peritoneal covering over the pelvic viscera. The obturator lymph nodes (green) are in the true pelvis with the obturator nerve, artery, and vein as it penetrates the levator ani. The perineum roof (levator ani muscle) is perforated by the urethra and houses the corpus cavernosum of the penis in the male and the vagina in the female.
The anatomic isocenters of the seven primary sites in the male genitourinary system are presented in multiplanar orientation diagrams (Fig. 34.4D,E). Each of the primary sites is presented in three planes—coronal, sagittal, and axial—as well as their sentinel and regional lymph nodes and adjacent organs.
The odyssey of the seven MGU primary sites is presented from cephalad to caudad (Table 34.3). The tabulation aligns each primary site with associated surrounding structures and osseous landmarks when feasible. The sentinel node for each primary site is also noted. The MGU tract includes highly vascular organs, placing them at high risk for hematogenous dissemination.
The MGU are in the true pelvis in juxtaposition to the alimentary system. The orientation three-dimensional/three-planar diagram is presented from cephalad to caudad, with the kidney ranging from T12 to L3, the ureters from L3 to S4, and the urinary bladder from S3 to S5. The prostate is at the coccyx, and the penis and testes are outside the bony pelvis and are perineal structures.
• The kidney is encased by a fibrous capsule and is surrounded by perirenal fat. The kidney is composed of the cortex, which includes glomeruli and convoluted tubules; and the medulla, which consists of the pyramids of converging tubules and the loops of Henle. The exterior two thirds of the kidney substance is the cortex, in contrast to the inner third, which is the medulla. The medulla contains 8 to 18 striated pyramids that send finge -like rays into the cortex and end in the minor calices. The minor calices unite and form the major calices, which drain into the renal pelvis. The hilus of the kidney has the pelvis, ureter, renal artery and veins, nerves, and lymphatics.
There are many structures that overlie the kidney; however, they are of little concern oncologically because the peritoneal lining essentially excludes the visceral structures it contains from direct invasion. Nevertheless, it is important to recognize the intimate relationships of the stomach on the left and the duodenum on the right and the location of the hepatic and splenic flexures of the colon in relation ship to the midportions of the kidneys. The lung overlies the upper poles of both kidneys due to the low insertion of the diaphragm, particularly during deep inspiration. One should be aware of the position of the pancreas, particularly of its head and tail and in regard to the right and left hila of the kidneys, respectively.
• The renal bed consists of renal fascia, which overlies the psoas major muscle and the quadratus lumborum musculature. The superior poles of both kidneys also lie in contact with the diaphragm. Usually, the 12th rib overlies the superior portion of the kidneys and is the only bone that is intimate anatomically. The kidney also lies opposite the transverse processes of T12 to L3.
• The course of the ureter is such that it is first crossed anteriorly by the renal artery and vein and then the testicular artery and vein in the male or the ovarian artery and vein in the female. In its continued descent retroperitoneally, the ureter passes anterior to the major iliac vessels. Before its insertion in the bladder, the vesical arteries and veins as well as the uterine artery and vein pass anteriorly to the ureter (“water under the bridge”). There are considerable variations in the anatomic relationships of the renal ureters with renal arteries and veins owing to normal anatomic variations of embryologic development that lead to different locations of the kidneys. In addition, anomalies in their development are common and include multiple renal arteries, fetal lobulations of the kidney, deflected and bifid ureters and pelves, and horseshoe and pelvic kidneys.
Figure 34.4 | Coronal (A) and sagittal (B) views with primary sites presented from cephalad to caudad at specific transverse level related to vertebrae.
ORIENTATION OF T-ONCOANATOMY: ODYSSEY OF PRIMARY SITES (CONTINUED)
The urinary bladder is the major collecting organ of urine. It is central to the anatomy and function of the urologic tract. The location of the bladder is inside the true pelvis when empty; however, it is a retroperitoneal abdominal organ when full. It relates to the pubic bone and musculature of the anterior abdominal wall and to the levator ani muscle laterally and inferiorly and to the content of the peritoneal cavity superiorly. The bladder's location requires knowledge of adjacent genital structures and disease. Symptomatology depends, in some part, on gender. The relationship of the ureters to surrounding blood vessels is important. The bladder is not a fixed structure but ha considerable capacity and mobility, altering its contour contact with the colointestinal viscera as it fills with urine
• The urinary bladder is a hollow viscus consisting of three layers: the mucosa and submucosa, the muscularis, and the serosa. The thickness of the wall depends on whether the bladder is expanded or contracted. In the male, the bladder is intimately related to the seminal vesicles posteriorly, the prostate inferiorly, and the pubis and peritoneum anteriorly. The seminal vesicles are situated between the bladder and the rectum. In the female, the vagina and cervix are located posteriorly to the bladder and the body of the uterus superiorly. The bladder is extraperitoneal, although the sigmoid colon and terminal portions of the ileum can be in contact with its superior peritoneal surface.
• The prostate gland is in the central location of the male pelvis and anatomically is positioned similar to the cervix in the female pelvis. The prostate gland—the largest accessory sex gland—is divided into several morphologic and functional zones. It consists of 30 to 50 tubuloalveolar glands arranged in three concentric layers: inner mucosal, an intermediate submucosal, and the peripheral layer containing the main prostatic glands.
• The peripheral zone corresponds to the main prostatic gland. It constitutes 70% of glandular tissue and gives rise to the majority of cancers. This is the most palpable part of the gland, which has a sulcus and feels bilobed after the major internal branching of the glands.
• The central zone contains less glandular tissue and is more resistant to both inflammation and cance.
• The transitional zone contains the mucosal glands, and this zone has a tendency to undergo extensive division or hyperplasia, forming benign nodular masses of epithelial cells. This benign prostate hyperplasia (BPH) results in difficulty voiding but is not the site of most malignant transformations.
• The periurethral zone contains mucosal and submucosal glands and may participate in BPH.
The prostate is firmly fixed in position by a dense capsu and ligamentous attachments. The urethra courses from the base of the bladder to the bulb of the penis. The cortical structure of the prostate's apex is directed below the perineum. Its flat base touches the base of the bladder, which has no fascia separating these two sites. Thus, the bladder is prone to direct invasion by prostate cancers as they advance. Posteriorly, Denonvilliers’ fascia separates the prostate gland from the rectum and acts as a major resistance to tumor invasion because it is composed of obliterated layers of the peritoneal cavity that extend downward. The ductus vas deferens and the seminal vesicles lie posterior to the bladder. They drain into the ejaculatory duct, which has the diameter of a lead pencil.
The penis is not a common cancer site, and neoplasms tend to locate around the glans or foreskin. They are considered to be associated with sexually transmitted papilloma virus and may frequently be manifested with partners who have cervical cancers. Penile cancers are squamous or basal cell.
Urethral cancers are more rare and tend to arise from the prostate urethral epithelium. Such malignancies can arise in females as well as males, but are quite rare.
The testis is a favored site for malignant disease in young adults, predominantly male, but account for only 1% of all male malignancies. Undescended testes (cryptorchidism) is a predisposing situation and is often corrected by puberty to avoid spermatogonia degeneration. A large variety of tumor types exist because of the germ cell origin and their different paths of differentiation and maturation. Two main categories are commonly noted: seminoma and nonseminoma, which include embryonal cancer and teratocarcinomas. The regional nodes are not regional, and their para-aortic location can be traced back to the gubernaculums during embryologic development when the testes are abdominal organs.
The scrotum also contains the vas deferens and its surrounding capsule, which includes several layers of the abdominal wall, which extend and envelope the testis. The muscular and fascial scrotal wall surrounding the testes is an extension of the anterior abdominal wall with similar layers of fascia but containing smooth muscle.
• The pelvic bony anatomy (Fig. 34.5A) houses the true pelvis which is defined by the pelvic rim
• The coronal section (Fig. 34.5B) defines the true pelvis i blue and accounts for intestinal content overlapping (purple) into pelvis.
• The compartments (Fig. 34.5C) indicate the urinary bladder occupies the true pelvis and the prostate in the male transitions as does the cervix into the perineum.
• The location of the abturator (internal iliac node) is again presented in distinction to external iliac node.
Figure 34.5 | Orientation of three-planar T-oncoanatomy. A. Three pelvic bones: The ilium holds the false pelvis or peritoneal cavity, and the pelvic inlet is framed by the ilium and the perineum by the pubic arch. B.Greater and lesser pelvis and perineum are color coded. C. Peritoneal cavity and extraperitoneal pelvic cavity and perineum with their contents. The anatomic landmarks aid in the search of the location of some MGU primary sites in the pelvis. (1) Iliac crest. (2) Iliac fossa. (3) Anterior superior iliac spine. (4) Ilium. (5) Pubis. (6) Ischium. (7) Sacral promontory. (8) Sacrum. (9) Coccyx. (10) Acetabulum. (11) Ischial spine. (12) Pubic tubercle. (13) Pubic symphysis. (14) Ala of ilium. (15) Lesser pelvis (pelvic cavity). (16) Perineum. (17) Greater brim. (18) Pelvic brim. (19) Pelvic diaphragm (levator ani and coccygeus muscles). (20) Iliopsoas muscle. (21) Parietal abdominal fascia. (22) Obturator internus muscle. (23) Pudendal canal. (24) Peritoneum. (25) Visceral pelvic fascia.
N-ONCOANATOMY
ORIENTATION OF N-ONCOANATOMY: REGIONAL LYMPH NODES
The next group of figures (Fig. 34.6A,B,C,D) provide the specific anatomic location of the regional lymph node station for each specific MGU primary site. The sentinel and regiona lymph nodes for each of male pelvic organs are listed in Table 34.4. Correlating the N-oncoanatomy in Figure 34.6 A,B,C,D with Table 34.4 assisting in understanding the variation in location of sentinel lymph nodes.
• Kidney. The renal hilar nodes are the first involved, and th renal lymphatics then follow the renal vein and enter paracaval and para-aortic nodes. Nodes in the retroperitoneal area inferior to the kidney are considered distant metastatic. Renal pelvis and ureters are similar, except that pelvic nodes are considered regional nodes (Table 34.4; Fig. 34.6A).
• Renal Pelvis and Ureters. The spermatic lymphatic collecting ducts on the right side tend to follow the vascular components of the spermatic cord and drain into the paracaval lymph nodes in the area where the spermatic vein enters the inferior vena cava and the artery arises from the aorta. The spermatic lymphatic collecting ducts on the left side also tend to follow the vascular components of the cord and drain into the para-aortic nodes in the region where the spermatic and the inferior mesenteric arteries arise out of the aorta and into the nodes of the left renal hilum in the region where the left spermatic vein joins the left renal vein. Juxtaregional nodes are those of the pelvis, but mediastinal and supraclavicular nodes are metastatic (Fig. 35.6B).
• Bladder. The bladder's rich lymphatic network of numerous small anterior vesical lymph nodes drains into three major routes: (i) the trigone, (ii) posterior and lateral walls, and (iii) anterior wall trunks. The regional or pelvic lymph nodes, located below the bifurcation of the common iliac arteries, include the internal iliacs, the hypogastric, the common iliac located above the pelvic basin, and the lateral, sacral, and anterior perivesicular nodes. The juxtaregional lymph nodes are the inguinal nodes, the high common iliac nodes, and the para-aortic nodes. The vessels, nerves, and lymphatics lie on the inner wall of the true pelvis, below the pelvic rim on the obturator muscle (Fig. 34.6B).
• Prostate Gland. The regional nodes are true pelvis nodes for the prostate gland. The lymphatic drainage of the prostate gland is to the obturator node, which is the sentinel node in the hypogastric or internal iliac chain. The obturator node is in the true pelvis, located alongside the obturator blood vessels, and is not in the medial chain of the external iliac chain in the false pelvis. The confusion is due to the projection in an anteroposterior pelvis radiograph, where the location of the obturator node appears to lie in a medial position but is actually posterior in the sagittal plane to the external iliac nodes, which are more anterior (Fig. 34.6C).
• Testis. The testis primary drainage on the right is to right inferior paracaval nodes and on the left to left renal hilus (Fig. 34.6C).
• Penis and Urethra. The lymphatic drainage is mainly to superficial inguinal and femoral nodes and then the external iliac nodes (Fig. 34.6D).
In addition, there is a rich network of lymphatics that drain into internal and external iliac nodes along the superior rectal veins and a posterior sacral trunk, which drains directly into para-aortic nodes. The nerves of the prostate are derived from the pelvic autonomic plexuses.
Figure 34.6 | Orientation of N-oncoanatomy. A. The lymphoid drainage of the major MGU organs in the male pelvis overlap. Lymphatic drainage of the ureters, urinary bladder, prostate, and urethra and lymphatic drainage of the testis, deferent duct, prostate, and seminal vesicles. (1) Renal hilar. (2) Renal pelvis and ureter. (3) Para-aortic and paracaval. (4) Common iliac. (4′) Presacral. (5) External iliac. (6) Internal iliac. (6′) Obturator. (7) Deep inguinal. (8) Superficial inguinal. (9) Femora. B-D. Lymphatic drainage of male pelvis and perineum. B. Lymphatic drainage and station for ureter and urinary Bladder. C. Lymphatic drainage and station for prostate and testes. D.Lymphatic drainage and station for penis, urethra, and scrotum.
M-ONCOANATOMY
M-ONCOANATOMY
Regional Veins
Each of the MGU organs has a distinct pattern of dissemination dictated in part by its anatomic location and in part by its venous drainage (Fig. 34.6A).
• Kidney: Renal cancers are highly vascular and may invade directly into the renal vein and into the inferior vena cava. They most often spread to the lung, extending into the heart as a tumor thrombus (Fig. 34.7A).
• Bladder: Cancers tend to be locally invasive and recur locally and metastasize late. Lymphatic spread is more frequent than distant metastases (Fig. 34.7B).
• Prostate: The veins are branches of the rectal (hemorrhoidal) and inferior vesical veins. The thin-walled veins are set inside and outside the prostatic capsule forming a plexus of prostatic-vesical veins. Prostate cancers preferentially seek bone. The osteoblastic distribution of metastases is largely confined to pelvic and vertebral bones and has bee attributed to Batson's vertebral venous plexus link to the periprostatic plexus (Fig. 34.7C).
• Testes: The spermatic artery and vein on the right side drain directly into the inferior vena cava. On the left side, they drain into the renal vein. This causes a higher pressure gradient in the left spermatic vein, which leads to a slight dilation of the pampiniform venous plexus that accounts for the lower-lying position of the left testicle as compared with the right. The testes target the para-aortic lymph nodes and then the mediastinal nodes (Fig. 34.7A).
• Penis: The dorsal vein of the penis drains into the periprostatic and perivesicular plexus and then the internal iliac vein, whereas the scrotum drains into the external iliac via the femoral and internal pudendal venous branches (Fig. 34.7B).
Figure 34.7 | Orientation of M-oncoanatomy. A. Great vessels, kidneys, and suprarenal glands. B. The pelvic veins and venous plexuses. C. Vertebral venous plexus (Batson's).
STAGING WORKUP
RULES OF CLASSIFICATION AND STAGING
Clinical Staging and Imaging
Clinical examination is limited and reliance on imaging is critical to properly stage cancer of the male genitourinary tract. Fortunately, modern imaging is superb and includes computed tomography (CT), magnetic resonance imaging (MRI), and selective arteriography. If the primary tumor is a renal parenchymal cancer, CT of chest for lung and mediastinal nodal metastases is advised. An intravenous pyelogram and routine laboratory studies are worthwhile. Bone scans are essential for suspected osseous metastases (Table 34.5; Fig. 34.8).
With radiologic imaging, the prostate's four compartments are visualized: the peripheral zone, the central zone, a transitional zone, and the periurethral zone. MRI allows for appreciating their relationship in axial, sagittal, and coronal views. The peripheral zone houses the majority of the branching tubuloalveolar glands and gives rise to 70% of adenocarcinomas, the submucosal glands in the central zone account for 10%, and transitional zone of mucosal glands account for 20% of cancers. The imaging procedures for the prostate gland adenocarcinoma serve as a model for the MGU because it is by far the commonest cancer.
PROGNOSIS AND CANCER SURVIVAL
Pathologic Staging
Careful assessment of resected primary tumor should be done with appropriate lymph nodes. All specimens should be carefully studied for clear margins.
Oncoimaging Annotations
• Cross-sectional imaging is essential in staging and treatment guidance.
• Although the reported staging accuracy for CT and MRI is similar, CT is used as a primary imaging approach; MRI complements CT and is most useful in defining the presenc and extent of intravenous tumor extension.
• Doppler ultrasonography is also recommended for the evaluation of vascular invasion.
• Pretreatment use of chest radiography versus chest CT is controversial. The use of chest CT is recommended when there is vascular tumor extension, the patient has chest symptoms, or a suspicious nodule is seen on the chest film
CANCER STATISTICS AND SURVIVAL
Cancers of the MGU constitute almost half of all malignancies in males. Malignancies of the male genital system account for approximately 350,000 new cancers, dominated by prostate cancer at 230,000, with the urinary system accounting for the remainder. Cancer deaths have been dramatically reduced, but annually prostate cancer still claims 30,000 lives and bladder cancer 15,000.
The most dramatic gains in survival are due to multidisciplinary approaches to diagnosis and detection and a transdisciplinary attack on MGU cancer. Over the last 50 years, prostate cancer 5-year survival rates improved by 50%, testes rates by 39%, and urinary bladder, kidney, and renal pelvis rates by 30%. Even more impressive are the MGU survival rates for stage I localized cancers, which are all 90% to 100% curable according to latest Surveillance Epidemiology and End Results data: kidney, 90%; bladder, 94%; testis, 99%; and prostate, 100%. These 5-year results are plotted in Figure 34.9 and shown in Table 34.6. The pediatric Wilms tumor of the kidney was the first solid malignanc cured by combining modalities in childhood neoplasms, achieving >90% long-term survival, along with Hodgkin’ s disease at around 70%. The reversal of a death sentence for these pediatric tumors is strikingly demonstrated in Figure 34.9. Equally important are improvements of quality of life owing to organ function preservation of the majority of prostate cancer patients.
Figure 34.8 | Coronal MRI correlates with the T-oncoanatomy coronal section (Fig. 34.5). Oncoimaging with CT is commonly applied to staging cancers, often combined with PET to determine true extent of primary cancer and involved lymph nodes. 1. Psoas m. 2. Iliacus m. 3. Transverse abdominis m. 4. Internal oblique m. 5. External oblique m. 6. Gluteus minimus m. 7. Gluteus medius m. 8. Obturator internus m. 9. Obturator externus m. 10. adductor group of muscles. 11. Vastus intermedius m. 12. Vastus lateralis m. 13. Levator ani m. 14. Bulbospongiosus m. 15. Ischiocavernosus m. 16. Lumbar spine 17. Acetabulum 18. Head of the femur. 19. Greater trochanter. 20. Internal iliac vessels. 21. Sigmoid colon. 22. Urinary bladder. 23. Prostate (central zone). 24. Prostate (peripheral zone).
Figure 34.9 | Trajectory of cancer survival for MGU organs. Prostate, bladder, testes, and Wilms’ tumor.