Testicular Cancer
NICE CKS Scrotal pain and swelling. Last revised: Aug 2024.
Overview of Testicular Cancer Types
This table provides a concise overview and allows direct comparison of various testicular cancer types. Further details are presented in the sections below.
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Cancer type
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Epidemiology
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Specific clinical Features
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Tumour Markers
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Histology Findings
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Germ cell tumour
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Seminoma
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Most common subtype
Majority of post-pubertal tumour
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Best prognosis due to slow growth and late metastasis.
Some may secrete β-hCG, leading to gynaecomastia.
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“Fried-egg” appearance and lymphocytic stroma.
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Yolk sac tumour
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Majority of pre-pubertal tumour
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Gross yellow mucinous cut surface (resemble primitive glomeruli)
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Choriocarcinoma
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Rare but considered the most aggressive subtype
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Almost always secretes β-hCG, often leading to gynaecomastia
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Contains syncytiotrophoblasts and cytotrophoblasts
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Teratoma
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Common in children (typically benign)
Rare in adults (can be malignant)
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Contains various tissue types such as teeth, cartilage, bone, and hair
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Non-germ cell tumour
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Leydig cell tumour
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Non-germ cell tumours make up ~5% of all testicular tumours (rare)
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Secretes testosterone, which can cause precocious puberty in boys
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Sertoli cell tumour
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Secretes oestrogen, which can lead to gynaecomastia
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Aetiology
Testicular cancer is the most common solid malignant tumour in young males (15-44 y/o) [Ref]
Key risk factors:
- Cryptorchidism (undescended testis) – most significant risk factor
- There is an increased risk even after orchiopexy surgery
- The risk is increased for both the undescended and the contralateral testis and persists after orchidopexy
- ↑ Risk of germ cell tumour
- Infertility / subfertility
- Klinefelter’s syndrome
- Hypospadias
- Family history of testicular cancer
- Contralateral testicular tumour
Types and Classification
Testicular cancer is divided into 2 main types, each with its own subtypes
Germ Cell Tumours (95%)
Germ cell tumours can be further divided into:
- Seminoma – most common (comparable to ovarian dysgerminoma in women)
- Non-seminomas:
- Teratoma
- Yolk sac tumour
- Choriocarcinoma
- Embryonal carcinoma
- Mixed germ cell tumour
Non-Germ Cell Tumours (5%)
There are 2 main non-germ cell tumours
- Leydig cell tumours
- Sertoli cell tumours
Epidemiology
Testicular tumours are the most common solid malignancy in young men (15-34 y/o)
- The majority of pre-pubertal tumours are yolk sac tumours (and teratomas)
- The majority of post-pubertal tumours are seminomas
Some other information: [Ref1][Ref2]
- Seminoma has the best prognosis (slow tumour growth and late metastases)
- Choriocarcinoma is the most aggressive
- Teratoma is common in children (typically benign), rare in adults (but can be malignant)
Clinical Features
Local Features
Unilateral testis enlargement / change in shape or texture
- Classic presentation: hard, irregular mass fixed to the testis
- Typically painless +/- dull ache or dragging sensation in the scrotum
An associated hydrocele is possible
- In a hydrocele, the testis is typically not palpable, making it hard to feel for any tumours.
- Therefore, scrotal ultrasound is essential in any new hydrocele in adults to exclude an underlying tumour
Metastasis
Lymphatic spread is most common:
- Para-aortic (retroperitoneal) lymphadenopathy (→ abdominal mass / pain / discomfort)
- Supraclavicular lymphadenopathy (Virchow node involvement) – only seen in advanced disease
High-yield anatomy + oncology fact:
- The penis (and scrotum) primarily drains lymph to the inguinal lymph nodes
- The testis primarily drains lymph to the para-aortic lymph nodes
Most common distant site of metastasis: lungs
Endocrine-Mediated Features
Only seen in certain tumours (mainly non-germ cell tumours):
- Gynaecomastia is seen in:
- Choriocarcinoma and embryonal carcinoma almost always secrete β-hCG, and sometimes seminomas
- Sertoli cell tumours (secrete oestrogen)
- Leydig cell tumours secrete testosterone → precocious puberty in boys (prominent external genitalia, pubic hair growth, mature masculine voice, accelerated skeletal and muscle growth)
Investigation and Diagnosis
Imaging
1st line: scrotal ultrasound [Ref]
- A solid intratesticular mass is malignant until proven otherwise
- Hypoechoic lesion compared with normal testicular tissue
- Irregular margins
2nd line: MRI
Tumour Markers
| Testicular cancer type | AFP | β-hCG | LDH |
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| Seminoma | Normal | ↑ in ~30% cases | ↑ in ~30% cases |
| Yolk sac tumour | ↑↑ | Normal | May be elevated |
| Choriocarcinoma | Normal | ↑↑ | May be elevated |
| Teratoma | Normal | Normal | May be elevated |
Non-germ cell tumours (i.e. Sertoli and Leydig cell tumours) are NOT associated with elevated tumour markers
Key patterns:
- ↑ AFP → yolk sac tumour
- ↑ β-hCG → choriocarcinoma (marked elevation) and some seminomas
- ↑ LDH → non-specific
Histology
Note that neither imaging nor tumour markers can provide a definitive diagnosis; orchiectomy for histology remains the primary diagnostic and therapeutic intervention [Ref]
Some key histological findings (simplified for exam purposes): [Ref]
- Seminoma → fried-egg appearance (large cells with clear cytoplasm and round nucleus) + lymphocytic stroma
- Teratoma → contains teeth, cartilage, bone, hair
- Choriocarcinoma → contains syncytiotrophoblasts and cytotrophoblasts
- Yolk sac tumour → gross yellow mucinous cut surface with Schiller-Durval bodies on microscopy, which resemble primitive glomeruli
Management
All patients require radical inguinal orchiectomy (for diagnostic and therapeutic purposes) [Ref1][Ref2]
Additional management: [Ref1][Ref2]
- Stage 1 cases can be managed with active surveillance and no additional management
- Higher-risk / advanced disease may need adjuvant chemotherapy and retroperitoneal lymph node dissection