Outcomes of Testicular Germ Cell Tumours: A Single-centre Study from the Sultanate of Oman

INTRODUCTION

Testicular cancer is a significant health concern for men, particularly those aged 20–40 years, ranking among the most common solid organ malignancies in this age group.¹ Although testicular cancer accounts for only 1–1.5% of all male cancers, its incidence has been increasing globally over recent decades. Most diagnoses occur between the ages of 20 and 34 years.² In Oman, testicular cancer is the 24^th most common malignancy, with an annual incidence of 10–15 new cases. Oman also has a predominantly young population, and thus, there is a greater need for targeted investigations and improved awareness about testicular cancer.³

This study examines the pathological characteristics and treatment outcomes of testicular germ cell tumour (TGCT) patients treated at Sultan Qaboos University Hospital (SQUH) from January 2006 to July 2023. By evaluating diagnostic patterns, therapeutic effectiveness, and potential complications, this work contributes to the regional understanding of management trends for TGCTs. Ultimately, the study seeks to improve outcomes and quality of life in affected individuals.

MATERIAL AND METHODS

Following approval from the Medical Research Ethics Committee (MREC #2933; Sultan Qaboos University [SQU]-EC/033/2022) at the College of Medicine and Health Sciences, SQU, we retrospectively reviewed the records of patients treated for testicular cancer at SQUH between 1 January 2006 and 31 July 2023. We identified 61 patients who underwent orchiectomy, and among them, 29 were suspected of having a testicular tumour and underwent radical inguinal orchiectomy. Demographic and perioperative data were retrieved from electronic patient records (EPRs) within the hospital information system (TrackCare^®). Histopathological details and outcomes after surgery and chemotherapy were also reviewed. Statistical analysis was performed using the Statistical Package for the Social Sciences version 27 (IBM, Armonk, NY, USA) to analyse the data obtained from EPRs. Continuous variables are presented as means, ranges, and standard deviations (SD), whereas categorical variables are presented as frequencies and percentages. Disease-free survival, recurrence and overall survival are discussed.

RESULTS

This study is a retrospective analysis of 61 patients with testicular tumours. Figure 1 shows the consort diagram of the patient who was included in the study with the final histopathology.

Close

Figure 1: The consort diagram of the patient who included in the study with the final histopathology.

Export to PPT

Most patients were Omanis (93%) from different regions of Oman [Figure 2]. The mean age of patients with testicular tumours was 28.7 ± 13.9 years. The mean age of patients with seminoma was 30.2 years (range: 23–40), while that of non-seminoma patients was 20.4 years (range: 15–33). For non-germ cell tumours, the mean age was 38.1 years (range: 13–68).

Close

Figure 2: The demography of patients with testicular tumour. The numbers in figure are the actual numbers from different regions of the country.

Export to PPT

The most common clinical presentation was painless, palpable testicular swelling, reported in 24 of 29 patients. Among the 29 cases, 13 involved the right testis, 15 involved the left, and 1 patient presented with a bilateral tumour. Six patients had a history of orchidopexy for an undescended testis. Ninety per cent (26) of patients underwent testicular ultrasonography, 22 (75.8%) had computed tomography scan and 11 (37.9%) had magnetic resonance imaging performed preoperatively.

Seminoma and non-seminoma germ cell tumours accounted for 52.4% and 47.6% of cases, respectively. The TNM and American Joint Committee on Cancer stages are illustrated in Figures 3 and 4.

Close

Figure 3: The T and N stage of the testicular germ cell tumours.

Export to PPT

Close

Figure 4: The American Joint Committee on Cancer stage of the testicular germ cell cancer.

Export to PPT

Seminoma is most prevalent in the 15–35 age group 72.7%, with a slightly higher prevalence in married patients 55.5% compared to single patients, 45.5%. Non-seminoma is predominantly found in the 15–35 years of age group, 90.0%, with a higher prevalence in single patients 60.0% compared to married patients (40.0%). Non-germ cell tumours are also most common in the 15–35 years of age group, 50.0%, with a higher prevalence in married patients 62.5% compared to single patients 37.5%. Table 1 demonstrates a comparison of tumour markers in the seminoma and non-seminoma groups. Overall, 61.9% of patients received adjuvant chemotherapy, most commonly bleomycin, etoposide and cisplatin (BEP).

At the last follow-up, 20 patients (95.2%) were disease-free. Figure 5 illustrates the management of different stages.

Close

Figure 5: Treatment types and lost to follow up at different stages. FU: Follow up, RPLND: Retroperitoneal lymph node dissection

Export to PPT

Chemotherapy-related side effects were observed in four patients and included gastrointestinal symptoms (nausea, vomiting, decreased appetite), alopecia and infertility. We reviewed the follow-up of 21 patients diagnosed with TGCT. The mean follow-up duration was 39.8 ± 18.2 months. At the last follow-up, 20 patients were disease-free, while one patient developed recurrent metastatic disease and subsequently died. Overall survival and recurrence-free rates was 90%.

DISCUSSION

In our study, the average age at diagnosis of testicular tumours was 28.7 years. This relatively young age aligns with the established epidemiology, which indicates that testicular tumours primarily affect men between 20 and 40 years of age.

Histopathological analysis identified TGCT in 21 patients: 11 had seminoma and 10 had non-seminomatous germ cell tumours. This distribution is consistent with prior research demonstrating that TGCT is the most common subtype of testicular tumours in younger men. Accurate identification of TGCT subtypes is essential to guide management and predict prognosis. All patients underwent inguinal orchidectomy for diagnostic and therapeutic purposes, consistent with international standards and findings from similar studies conducted in Japan.⁴

Most of the patients (52.4%) presented with Stage 1 disease, indicating localised tumours confined to the testis. Stage 2 disease was observed in 19.0% of patients, while 28.6% presented with Stage 3 disease, characterised by distant metastases findings comparable to those reported in Japanese cohorts.⁴ Following orchidectomy, treatment varied based on stage and pathology. In our study, 13 patients (61.9%) received chemotherapy, most commonly BEP, followed by EP, while 8 patients (38.1%) were managed with active surveillance. Although surveillance avoids treatment-related toxicities, it requires strict adherence to follow-up due to higher recurrence rates.⁵

Chemotherapy, while highly effective, is associated with both acute and long-term adverse effects. In our cohort, four patients experienced gastrointestinal symptoms, alopecia, neuropathy and infertility. These findings underscore the importance of long-term monitoring for survivors and the continued need to optimise treatment regimens to reduce toxicity.⁶

The mean follow-up duration was 39.8 months, with a SD of 18.2 months, reflecting variation influenced by disease stage, treatment modality and patient-specific factors. Encouragingly, 95.2% of patients remained disease-free at last follow-up. However, disease-free status does not equate to cure; long-term vigilance is essential.⁷ Recurrence resulting in mortality illustrates the potential aggressiveness of advanced or refractory TGCT. Age distribution patterns in our study also align with global reports, with the highest incidence among men aged 15–35 years. Non-seminomas tended to present at younger ages, consistent with findings from a 2023 study from Jordan.⁸ The mean duration of symptoms was 62 weeks, indicating delayed medical consultation. This contrasts with a Dutch study reporting a median diagnostic delay of only 30 days.⁹ Sociodemographic factors such as rural residence, older age, absence of an intimate partner and embarrassment may contribute to delays and highlight the need for targeted awareness campaigns.¹⁰

A study from Saudi Arabia reported similar clinical patterns with only minor differences in proportions.⁹ Tumour marker analysis can aid in personalised management. Elevated human chorionic gonadotropin (hCG) levels were observed in both seminoma and non-seminoma tumours, consistent with its production by syncytiotrophoblastic cells.¹⁰ AFP elevation occurred exclusively in non-seminomas, as expected, supporting our findings shown in Figure 2. Levels of AFP and hCG were generally higher in non-seminomas, in agreement with previous studies, although absolute values varied due to differing measurement units and population characteristics. Lactate dehydrogenase, while less specific, remains useful for surveillance.¹¹

Chemotherapy-related toxicities encompass cardiovascular and metabolic disorders, secondary malignancies, avascular necrosis, cognitive impairments, cancer-related fatigue, diminished mental health-related quality of life, nephrotoxicity, hypogonadism, neurotoxicity, pulmonary toxicity, as well as anxiety and depression.¹²

When identified early, with the disease confined to the testicle (Stage I), long-term outcomes are excellent, with a 5-year survival rate approaching 99%. Even in cases of metastatic disease (stages II and III), modern treatments continue to provide favourable results, with 5-year survival rates around 92% for Stage II and approximately 85% for Stage III.¹³ Early detection enables prompt treatment, typically radical inguinal orchiectomy, reducing the need for more aggressive therapies or later, more complex interventions.¹⁴ Since most TGCT present as a painless testicular mass that patients often do not notice, awareness and timely evaluation, such as through a medical exam or scrotal ultrasound, are essential for catching the disease in its early stages.

CONCLUSION

This study demonstrates that the distribution of histological subtypes and age at presentation aligns with international literature. Gaps in adherence to follow-up protocols highlight the need for enhanced health education to encourage earlier medical consultation and compliance with surveillance programmes. Findings from this single centre may motivate broader national efforts to evaluate and report oncological outcomes, ultimately improving the standard of care for patients in the Sultanate of Oman. Further multicentre studies or establishment of a national TGCT registry are recommended.