Testicular neoplasms fall into two main categories: germ cell tumours sex cord-stromal tumours. The Leydig cells and the
Sertoli cells are the two somatic cell types that give rise to sex cord-stromal tumours. Leydig cell tumours of the testis are
rare, accounting for 1% to 3% of all testicular neoplasms although they are the most prevalent interstitial neoplasms of
the testis2. Though LCTs can happen at any age, they are more common in men between the ages of 30 - 60 years and
prepubertal boys, who are typically between the ages of 5 - 10 years7,8. LCTs are always benign in children and
malignant in 10% adult cases, accounts for a disease-specific mortality rate 6.6%9,10,11. Benign LCTs are traditionally
treated with orchiectomy and malignant LCTs are treated by orchiectomy combined with retroperitoneal
lymphadenectomy12. Here, we present a case report on adult type Leydig cell tumor of the testis with atypical
histopathological findings: a diagnostic challenge. In our case a 75years old male presented to the OPD with left scrotal
swelling. USG showed an ill-defined lesion in left testis. He underwent left high inguinal orchidectomy, gross
examination of the specimen showed a 7.5×5×4 cm heterogenous mass in left testis. On microscopical examination of
H&E stained section showed monomorphic polygonal cells with eosinophilic cytoplasm arranged in insular pattern
having rounded nuclei with granular chromatin and absence of prominent nucleoli. Immunohistochemistry showed the
tumor was positive for -inhibin and vimentin and negative for chromogranin A, synaptophysin, SALL-4, OCT3/4. The
presence of these atypical histopathological features in our case led to a diagnostic dilemma, which was further
overcome by IHC findings. So, this case report and result signifies the importance of IHC for accurate diagnosis and
management of the patients with testicular tumor.