Leydig Cell Tumour

Leydig cell tumour, also known as testicular interstitial cell tumour, is part of the sex cord-stromal tumour group of ovarian and testicular cancers. It arises from Leydig cells and is most commonly diagnosed in young adults, though it can occur at any age.

A Sertoli–Leydig cell tumour is a combination of Leydig cell tumour and Sertoli cell tumour arising from Sertoli cells.

Introduction

Presentation

In males, Leydig cell tumours usually manifest in two age groups: 5–10 years and 30–60 years. Children typically present with precocious puberty. In females, one-third of patients exhibit progressive masculinisation due to excess testosterone secreted by the tumour.

This masculinisation is often preceded by anovulation, oligomenorrhea, amenorrhea, and defeminisation. Additional signs in females include acne, hirsutism, voice deepening, clitoromegaly, temporal hair recession, and increased musculature, along with elevated serum testosterone levels.

In men, the most common presenting feature is testicular swelling. Additional symptoms vary based on the tumour's hormonal activity.

Tumours secreting androgens are often asymptomatic but can cause precocious puberty in pre-pubertal boys.

Tumours secreting oestrogens can result in feminisation in young boys and various problems in adults, including gynaecomastia, erectile dysfunction, infertility, feminine hair distribution, gonadogenital atrophy, and loss of libido.

Cause

Animal studies suggest a potential link between Leydig cell tumours and exposure to C8 (C8HF15O2, perfluorooctanoic acid).

Diagnosis

The presence of an ovarian tumour accompanied by hormonal disturbances may point towards a Leydig cell tumour, granulosa cell tumour, or thecoma. However, hormonal disturbances are observed in only two-thirds of Leydig cell tumour cases. In men, testicular Leydig cell tumours can be detected sonographically, and ultrasound examinations may be ordered in the presence of a palpable scrotal lump. Incidental identification of these lesions is also possible.

A definitive diagnosis is established through histological analysis, typically performed during or after surgery. Reinke crystals, although present in less than half of all cases, can confirm the diagnosis. Immunohistochemical markers for Leydig cell tumours include inhibin-alpha, calretinin, and melan-A.

Treatment

Chemotherapy regimens show limited efficacy in treating Leydig cell tumours, although imatinib has shown some promise. Radiotherapy does not currently play a role in treatment. The primary treatment is surgery. In females, this typically involves a fertility-sparing unilateral salpingo-oophorectomy. For malignant tumours, more radical surgery followed by adjuvant chemotherapy and sometimes radiation therapy may be necessary. Post-treatment surveillance focuses on repeated physical examinations and imaging due to the lack of elevated tumour markers in many cases.

In males, the typical surgical approach is a radical inguinal orchiectomy. However, testes-sparing surgery can be performed to preserve fertility in children and young adults. This involves an inguinal or scrotal incision and ultrasound guidance if the tumour is non-palpable. This approach is viable because the tumour is typically unifocal, not associated with precancerous lesions, and unlikely to recur.

The prognosis for Leydig cell tumours is generally favourable as they tend to grow slowly and are usually benign, with only 10% being malignant. However, the prognosis is poor for malignant tumours with undifferentiated histology.

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Self-assessment MCQs (single best answer)

What age groups are most commonly diagnosed with Leydig cell tumours in males?

What is the primary presenting feature of Leydig cell tumours in men?

Which of the following is NOT a symptom of Leydig cell tumour in females?

What histological feature can confirm the diagnosis of a Leydig cell tumour?

Which imaging modality is commonly used to detect Leydig cell tumours in men?

Which chemotherapeutic agent has shown promise in the treatment of Leydig cell tumours?

What is the primary treatment for Leydig cell tumours?

Which immunohistochemical marker is NOT associated with Leydig cell tumours?

What is the typical surgical approach for Leydig cell tumours in males?

What is the prognosis for Leydig cell tumours?