35 Testis
35
SUMMARY OF CHANGES
• The definitions of TNM and the Stage Grouping for this chapter have not changed from the Fifth Edition.
C62.0 Undescended testis C62.1 Descended testis C62.9 Testis, NOS
INTRODUCTION
Cancers of the testis are usually found in young adults and account for less than 1% of all malignancies in males. However, during the twentieth century, the inci- dence has more than doubled. Cryptorchidism is a predisposing condition, and other associations include atypical germ cells and multiple atypical nevi. Germ cell tumors of the testis are categorized into two main histologic types: semino- mas and non-seminomas. The latter group is composed of either individual or combinations of histologic subtypes, including embryonal carcinoma, teratoma, choriocarcinoma, and yolk sac tumor. The presence of serum markers, includ- ing alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and lactate dehydrogenase (LDH), is frequent in this disease. Staging and prognostication are based on the determination of the extent of disease and assessment of serum tumor markers. Cancer of the testis is highly curable, even in cases with advanced, metastatic disease.
ANATOMY
Primary Site. The anatomy of the testes is illustrated in Figure 35.1. The testes are composed of convoluted seminiferous tubules with a stroma containing functional endocrine interstitial cells. Both are encased in a dense capsule, the tunica albuginea, with fibrous septa extending into the testes and separating them into lobules. The tubules converge and exit at the mediastinum of the testis into the rete testis and efferent ducts, which join a single duct. This duct—the epididymis—coils outside the upper and lower poles of the testicle and then joins the vas deferens, a muscular conduit that accompanies the vessels and lym- phatic channels of the spermatic cord. The major route for local extension of cancer is through the lymphatic channels. The tumor emerges from the medi- astinum of the testis and courses through the spermatic cord. Occasionally, the epididymis is invaded early, and then the external iliac nodes may become involved. If there has been previous scrotal or inguinal surgery or if invasion of the scrotal wall is found (though this is rare), then the lymphatic spread may be to inguinal nodes.
Regional Lymph Nodes. The following nodes are considered regional (Figure 35.2):
Interaortocaval
Para-aortic (periaortic)
304 American Joint Committee on Cancer • 2006 Paracaval
Preaortic Precaval Retroaortic Retrocaval
The intrapelvic, external iliac, and inguinal nodes are considered regional only after scrotal or inguinal surgery prior to the presentation of the testis tumor.
C62.1
FIGURE 35.1. Anatomy of the testis.
C77.2
C77.5
C77.4
C77.4 and 5 only
after scrotal or inguinal surgery
FIGURE 35.2. Regional lymph nodes of the testis.
All nodes outside the regional nodes are distant. Nodes along the spermatic vein are considered regional.
Metastatic Site. Distant spread of testicular tumors occurs most commonly to the lymph nodes, followed by metastases to the lung, liver, bone, and other visceral sites. Stage is dependent on the extent of disease and on the determination of serum tumor markers. Extent of disease includes assessment for involvement and size of regional lymph nodes, evidence of disease in nonregional lymph nodes, and metastases to pulmonary and non-pulmonary visceral sites. The stage is subdivided on the basis of the presence and degree of elevation of serum tumor markers. Serum tumor markers are measured immediately after orchiectomy and, if elevated, should be measured serially after orchiectomy to determine whether normal decay curves are followed. The physiological half-life of AFP is 5–7 days, and the half-life of HCG is 24–
48 hours. The presence of prolonged half-life times implies the presence of residual disease after orchiectomy. It should be noted that in some cases, tumor marker release may occur (for example, in response to chemotherapy or handling of a primary tumor intraoperatively) and may cause artificial eleva- tion of circulating tumor marker levels. The serum level of lactate dehydroge- nase (LDH) has prognostic value in patients with metastatic disease and is included for staging.
DEFINITIONS Primary Tumor (T)
(1)The extent of primary tumor is usually classified after radical orchiectomy, and for this reason, a pathologic stage is assigned.
pTX Primary tumor cannot be assessed (if no radical orchiectomy has been performed, TX is used)
pT0 No evidence of primary tumor (e.g., histologic scar in testis) pTis Intratubular germ cell neoplasia (carcinoma in situ)
pT1 Tumor limited to the testis and epididymis without vascular/lymphatic invasion; tumor may invade into the tunica albuginea but not the tunica vaginalis (Figure 35.3A)
pT2 Tumor limited to the testis and epididymis with vascular/lymphatic inva- sion, or tumor extending through the tunica albuginea with involvement of the tunica vaginalis (Figures 35.3A, B)
pT3 Tumor invades the spermatic cord with or without vascular/lymphatic invasion (Figure 35.4)
pT4 Tumor invades the scrotum with or without vascular/lymphatic invasion (Figure 35.5)
Regional Lymph Nodes (N) Clinical
NX Regional lymph nodes cannot be assessed N0 No regional lymph node metastasis
N1 Metastasis with a lymph node mass 2 cm or less in greatest dimension; or multiple lymph nodes, none more than 2 cm in greatest dimension (Figures 35.6A–F)
35
T. vaginalis
pT1= without vascular/
lymphatic invasion
pT2= with vascular/
lymphatic invasion
T. albuginea
A
T. vaginalis T. albuginea
pT2
B FIGURE 35.3. A. Illustration of pT1 and pT2 showing tumor without and with vascular/
lymphatic invasion. B. pT2 tumor extending through the tunica albuginea with involvement of the tunica vaginalis.
pT3
FIGURE 35.4. pT3 tumor invades the spermatic cord.
pT4
FIGURE 35.5. pT4 tumor invades the
scrotum.
35
FIGURE 35.6. A. N1 is defined as metastasis with a lymph node mass 2 cm or less in greatest dimension. B. N1: metastasis in multiple lymph nodes, none more than 2 cm in greatest dimension. C. N1: metastasis with a lymph node mass 2 cm or less in greatest dimension, following scrotal or inguinal surgery.
N1
£2 cm
A
N1
£2 cm
B
After scrotal or inguinal surgery
£2 cm
N1
C
308 American Joint Committee on Cancer • 2006
After scrotal or inguinal surgery
£2 cm
N1
D
N1 pN2
>2-<5 cm
£2 cm
E
FIGURE 35.6. D. N1: metastasis in
multiple lymph nodes, none more
than 2 cm in greatest dimension,
following scrotal or inguinal
surgery. E. N1 (left) is defined as
metastasis in multiple lymph nodes,
none more than 2 cm in greatest
dimension. pN2 (right) is defined
as more than 5 nodes positive,
more than 2 cm but none larger
than 5 cm in greatest dimension.
35
N1 pN2
£2 cm
Extranodal extension
£2 cm
F
FIGURE 35.6. F. N1 (left) defined as metastasis with a lymph node mass 2 cm or less in greatest dimension. pN2 (right) defined as of extranodal extension of tumor.
N2 Metastasis with a lymph node mass more than 2 cm but not more than 5 cm in greatest dimension; or multiple lymph nodes, any one mass greater than 2 cm but not more than 5 cm in greatest dimension (Figures 35.7A–C) N3 Metastasis with a lymph node mass more than 5 cm in greatest dimension
(Figures 35.8A–D)
Regional Lymph Nodes (N) Pathologic
pNX Regional lymph nodes cannot be assessed pN0 No regional lymph node metastasis
pN1 Metastasis with a lymph node mass 2 cm or less in greatest dimension and less than or equal to 5 nodes positive, none more than 2 cm in great- est dimension
pN2 Metastasis with a lymph node mass more than 2 cm but not more than
5 cm in greatest dimension; or more than 5 nodes positive, none more
than 5 cm; or evidence of extranodal extension of tumor (Figures 35.6E,
F; Figures 35.7A–C)
310 American Joint Committee on Cancer • 2006
N2 pN2
>2-5 cm
A
N2 pN2
>2-5 cm
B
After scrotal or inguinal surgery
>2-5 cm
N2 pN2
C
FIGURE 35.7. A. N2/pN2:
metastasis with a lymph node mass more than 2 cm but not more than 5 cm in greatest dimension.
B. N2/pN2: metastasis in multiple lymph nodes, any one mass greater than 2 cm but not more than 5 cm in greatest dimension. C.
N2/pN2: metastasis with a
lymph node mass more
than 2 cm but not more
than 5 cm in greatest
dimension, following scrotal
or inguinal surgery.
35
>5 cm
N3 pN3
A
After scrotal or inguinal surgery
>5 cm
N3 pN3
B FIGURE 35.8. A. N3/pN3:
metastasis with a lymph node mass
more than 5 cm in greatest
dimension. B. N3/pN3 metastasis
with a lymph node mass more than
5 cm in greatest dimension,
following scrotal or inguinal
surgery.
312 American Joint Committee on Cancer • 2006 FIGURE 35.8. C. N3/pN3:
metastasis with a lymph node mass more than 5 cm in greatest dimension. As illustrated here, multiple nodes are involved with one nodal mass exceeding 5 cm. D.
N3/pN3: metastasis with a lymph node mass more than 5 cm in greatest dimension. As illustrated here following scrotal or inguinal surgery, multiple nodes are involved with one nodal mass exceeding 5 cm.
>5 cm
N3 pN3
C
After scrotal or inguinal surgery
>5 cm
