Gynecomastia is the most common definition of breast tissue growth. It is common in urology due to androgen blockage used in prostate cancers. Clinically
insignificant gynecomastia is present in 50% of men and there is no proliferation
of breast tissue in ductus epithelium. Gynecomastia is rarely seen in primary testicular tumors such as Leydig Cell Tumors (LCT). Leydig Cell Tumors are one of
the rare sex cord stromal cell tumors of the testis. Although it is usually with endocrine changes, it is a painless mass or incidentally occurring tumor in the testis.
In this case report, we examined a 43-year-old left testicular Leydig cell tumor
followed up with gynecomastia. He had been admitted to our clinic for gynecomastia and breast pain for 6 years. The patient was followed-up by endocrinology due to the aforementioned complaints. Pituitary MRI was performed with the
suspicion of prolactinoma, but no pathology was found. Since the physical examination was unremarkable, MRI of the lower abdomen was requested from the
patient. MRI reported as 20*20 mm in size (testicular tumor?) in the left intratesticular area. The patient underwent left inguinal orchiectomy and the pathology report was positive for the leydig cell tumor. 30% of patients with Leydig
cell tumors present with gynecomastia. Ultrasonography is accepted as the first
research method for the diagnosis of leydic cell tumor, but MRI is superior to
ultrasonography in diagnosis. The gold standard treatment option is radical inguinal orchiectomy. The mechanism of hormonal disorders may be an overproduction of testosterone and estrogens by the tumor. As in our case, it is necessary to
consider the possibility of LCT which is rarely seen in patients with gynecomastia
and to provide differential diagnosis by performing the tests in this direction.