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Four testicular biopsies failing to detect a case of testicular intraepithelial neoplasia

All testicular germ cell tumours (GCTs) develop through the precursor stage testicular intraepithelial neoplasia (TIN; also called carcinoma in situ). TIN is present in the testis many years before the clinical manifestation of the tumour (1, 2). Early detection of testicular cancer is possible by testicular biopsy with histological searching for TIN. The accuracy of the testicular biopsy to detect TIN is fairly high. The proportion of false-negative biopsies is reportedly in the region of 0.5% (3). Here we report on a case of testicular tumour that developed despite a total of four testicular biopsies being negative for TIN. Case report. A 31-year-old man underwent left-sided inguinal orchiectomy for pure seminoma in another institution. No metastases were found, radiologically. Consecutively, the patient received prophylactic abdominal radiotherapy at a dosage of 26 Gy for a presumed clinical stage I seminoma. Contralateral biopsy had not been performed because the right-sided testicle had appeared normal upon palpation and ultrasonography, and, moreover, the patient’s history was without any particular risk factor, e.g. history of cryptorchidism or familial testicular cancer. Two years later, a small hypoechoic intratesticular lesion was detected sonographically during follow-up (Fig. 1). Clinical examination and tumour marker analysis were normal, but magnetic resonance imaging (MRI) of the testis confirmed the presence of a small intratesticular mass at the cranial /dorsal site (Fig. 2). Consecutively, surgical inguinal exposure of the testis was performed. Surprisingly, no tumour could be identified despite intensive intraoperative palpation and ultrasound imaging. To rule out malignancy, a small specimen of testicular tissue was excised from the presumed location of the suspected neoplasm and, in addition, a total of three testicular biopsies were taken from different parts of the testicular parenchyma. The surgical procedure was then terminated. Recovery was uneventful. All four of the biopsy specimens had been fixed in Stieve’s solution and all of them were larger than 3 mm in diameter. Immunohistological examination involving staining of placental alkaline phosphatase (PLAP) was negative for TIN in all of the specimens. Upon re-examination one year later, the intratesticular mass had slightly increased in size, both sonographically and by MR imaging (Fig. 3). Repeat surgical exploration now disclosed a tiny palpable tumour located close to the rete testis. Partial orchidectomy was performed with preservation of the right