Benign ultrasound in a young adult with pT2 seminoma – beware the malignant potential of undescended testes

Undescended testicles (UDTs) in post-pubertal males, while uncommon in high-income countries, pose a serious risk of malignancy if undetected. While most will descend spontaneously during the first year of life (only 1% of boys have UDT at 12-months of age), they may pose a risk of malignancy if left untreated. The relative risk of testicular malignancy in males who undergo repair after age 13 is still 5.4-fold higher than the general population. We describe the first case of locally invasive testicular seminoma in a young man with unilateral cryptorchidism and an otherwise nonconcerning appearance on ultrasound. A 24-year-old male presented to his General Practitioner with left lower abdominal pain suspected to be an inguinal hernia. The patient was under the impression that he had single right testis, with the left testis absent since birth. As the patient was born in a low/ middle-income country, no further investigations were performed to locate the absent testis. Workup with ultrasound showed a normal intrascrotal right testis (11 cc). The left testis was found to be atrophic (4 cc) and situated in the inguinal canal, proximal to the pubic symphysis. There were no ultrasound findings suggestive of malignancy (Fig. 1). Tumour markers including alpha fetoprotein (AFP), beta-human chorionic gonadotropin (βHCG) and lactate dehydrogenase (LDH) were within the normal range. Subsequent examination by a urologist confirmed the presence of a normal right testis and an undescended left inguinal testis. Manual assessment of the left testis was limited by small size. The patient was recommended upfront orchidectomy as the gold standard of treatment. As an alternative, the patient was offered 3-monthly ultrasound surveillance for potential malignant change – this was the less preferred open and deviated from recommended guidelines. The patient subsequently underwent an uncomplicated left inguinal orchidectomy. Histopathology revealed an invasive 11 mm pure seminoma with extensive involvement of the rete testis; surgical margins were clear. There was no apparent lymphovascular invasion, however, malignant invasion of peritesticular/hilar soft tissue staged this cancer as pT2 (Fig. 2). Post-operative computed tomography scan of the chest, abdomen and pelvis excluded retroperitoneal or lymph node disease. Following discussion in the multidisciplinary cancer meeting, the patient was referred to medical oncology for consideration of surveillance versus single-dose platinum-based chemotherapy. The patient opted for active surveillance. Normal testicular descent begins in the fourth foetal month and descends into the scrotum by the seventh month. However, as a result of maternal factors, congenital syndromes and/or preterm birth, a unilateral testis or bilateral testes may not descend appropriately into the scrotum – this is known as cryptorchidism. Of undescended testes, 70% are palpable and typically located in the inguinal region. The remaining 30% are non-palpable and may be intra-abdominal, ectopic or absent. Studies are ongoing to better understand the mechanism underlying cryptorchidism and its association with testicular cancer. Some hypotheses suggest it may be due to disruptions in androgen-signalling pathways. Absent testes in adults should be located or confirmed absent with imaging due to the increased risk of malignancy. Men with cryptorchidism are 3.7–7.5 times more likely to develop testicular

Undescended testicles (UDTs) in post-pubertal males, while uncommon in high-income countries, pose a serious risk of malignancy if undetected. 1,2 While most will descend spontaneously during the first year of life (only 1% of boys have UDT at 12-months of age), they may pose a risk of malignancy if left untreated. The relative risk of testicular malignancy in males who undergo repair after age 13 is still 5.4-fold higher than the general population. 3 We describe the first case of locally invasive testicular seminoma in a young man with unilateral cryptorchidism and an otherwise nonconcerning appearance on ultrasound.
A 24-year-old male presented to his General Practitioner with left lower abdominal pain suspected to be an inguinal hernia. The patient was under the impression that he had single right testis, with the left testis absent since birth. As the patient was born in a low/ middle-income country, no further investigations were performed to locate the absent testis. Workup with ultrasound showed a normal intrascrotal right testis (11 cc). The left testis was found to be atrophic (4 cc) and situated in the inguinal canal, proximal to the pubic symphysis. There were no ultrasound findings suggestive of malignancy ( Fig. 1). Tumour markers including alpha fetoprotein (AFP), beta-human chorionic gonadotropin (βHCG) and lactate dehydrogenase (LDH) were within the normal range.
Subsequent examination by a urologist confirmed the presence of a normal right testis and an undescended left inguinal testis. Manual assessment of the left testis was limited by small size. The patient was recommended upfront orchidectomy as the gold standard of treatment. As an alternative, the patient was offered 3-monthly ultrasound surveillance for potential malignant changethis was the less preferred open and deviated from recommended guidelines.
The patient subsequently underwent an uncomplicated left inguinal orchidectomy. Histopathology revealed an invasive 11 mm pure seminoma with extensive involvement of the rete testis; surgical margins were clear. There was no apparent lymphovascular invasion, however, malignant invasion of peritesticular/hilar soft tissue staged this cancer as pT2 (Fig. 2).
Post-operative computed tomography scan of the chest, abdomen and pelvis excluded retroperitoneal or lymph node disease. Following discussion in the multidisciplinary cancer meeting, the patient was referred to medical oncology for consideration of surveillance versus single-dose platinum-based chemotherapy. The patient opted for active surveillance.
Normal testicular descent begins in the fourth foetal month and descends into the scrotum by the seventh month. 2 However, as a result of maternal factors, congenital syndromes and/or preterm birth, a unilateral testis or bilateral testes may not descend appropriately into the scrotumthis is known as cryptorchidism. 4 Of undescended testes, 70% are palpable and typically located in the inguinal region. The remaining 30% are non-palpable and may be intra-abdominal, ectopic or absent. 5 Studies are ongoing to better understand the mechanism underlying cryptorchidism and its association with testicular cancer. Some hypotheses suggest it may be due to disruptions in androgen-signalling pathways. 2 Absent testes in adults should be located or confirmed absent with imaging due to the increased risk of malignancy. Men with cryptorchidism are 3.7-7.5 times more likely to develop testicular cancer. 6 In men who develop testicular cancer, 5-10% have a history of cryptorchidism. 6 Post-pubertal men who receive orchiopexy for cryptorchidism remain twice as likely to develop testicular cancer than those who receive treatment before 13-years of age. 3 While ultrasound is accurate for the identification of intrascrotal testicular tumours, 7 there is a paucity of evidence demonstrating its ability to identify cancer in undescended testes.
Early referral to a urologist is required for all adult males with unrepaired cryptorchidism. A careful discussion is warranted regarding the risks and benefits of surgery or surveillance. Peerreviewed guidelines recommend orchidectomy for post-pubertal males with cryptorchidism to minimise cancer risk. 8,9 Surveillance is only suggested in older patients with significant anaesthetic risk. 8 Besides the risk of malignancy, undescended testes do not appear to increased the risk of fertility 3 or testicular torsion. 10 Our case highlights the importance of adhering to best-practice guidelines when managing undescended testes in post-pubertal men. If, after patient counselling, a surveillance approach is sought the current case highlights that ultrasound may be unreliable in identifying malignancy change in a cryptorchid testis. Thus, we continue to advocate for early orchidectomy.