Terato-Neuroendocrine Tumour of Testis: Review and Update
Authors: Kodzo-Grey Venyo Anthony 
Published: August 2024

Neuro-endocrine tumours commonly emanate from intestinal and respiratory epithelium. Neuro-endocrine tumours could also on rare occasions afflict various organs of the human body. Neuro-endocrine tumour afflicting the testis is an uncommon tumour which does account for far less than one percent (<1%) of all tumours of testis. To the knowledge of the author, less than 100 cases of primary neuro-endocrine tumour of the testis had been reported so far in the global literature. The reported cases of neuro-endocrine tumour of testis have ranged between 10 years and 83 years of age and the reported incidence rate had been noted to be higher within the fifth and sixth decade of life. Majority of patients who are afflicted by neuro-endocrine tumour of testis do tend to manifest with unilateral painless testicular mass. Sixteen percent (16%) of patients who are afflicted by neuro-endocrine tumour of testis do manifest with symptoms of neuroendocrine tumour syndrome. Eleven percent (11%) of primary neuroendocrine tumours of testis tend to be diagnosed initially with a contemporaneously-associated metastasis. Neuro-endocrine tumours of the testis occur as a primary testicular neuroendocrine tumour, or they may be metastatic neuroendocrine tumour to the testis with the primary tumour originating from elsewhere in the body especially from the gastrointestinal or cardiorespiratory tract system. Primary neuro-endocrine tumour of testis, could be further sub-divided into: (a) primary pure neuroendocrine tumour of testis; and (b) neuro-endocrine tumour of testis contemporaneously associated with teratoma or dermoid/epidermoid cysts. Once a neuro-endocrine tumour of testis is diagnosed, it is pivotal that clinicians should exclude a metastatic neuroendocrine tumour to the testis with the primary tumour originating from elsewhere within the human body. It has been iterated that the presence of teratomas elements within the neuro-endocrine tumour of testis does sufficiently rule out the primary site outside the testis. In order to accurately diagnose the neuro-endocrine tumour of the testis, it has been advised that it is pertinent to submit the tumour mass entirely and to look for any additional lineage of differentiation. Twenty five percent of primary neuro-endocrine tumours of testis are associated with teratoma. Histogenesis of pure neuroendocrine tumour of the testis is yet to be clarified. Two postulates had been propounded in relation to the mode origin of neuroendocrine tumour of testis including: (1) Emanation from a teratoma which is the germ cell origin postulate; (2) Emanating from argentaffin cells that are located within crypts of Lieberkühn .A study related to three pure testicular neuroendocrine tumours of testis had indicated that pure neuroendocrine tumour of testis might have different genetic background other than germ cell tumour.[11] Histopathology examination of specimens of neuro-endocrine tumour of testis has tended to demonstrate tumour cells that tend to be typified by the presence of nests of small round cells with uniform nuclei forming small acini and rosettes or sheets. The cells tend to contain eosinophilic granules within the cytoplasm and granular chromatin within the nuclei. The tumour cells do exhibit positive staining for neuroendocrine markers like chromogranin and synaptophysin as illustrated in detail in the article. Radical orchidectomy is the most adopted option of treatment; nevertheless, necessitation for the undertaking of provision of adjuvant treatment depending upon histological grading has not been clarified. Because of the possibility of development of local recurrence and or distant metastases after a long time, it is pivotal for all clinicians to carefully follow-up their patients over a long-period of time with clinical, laboratory testing and radiology-imaging testing follow-ups in order to establish early diagnosis of any local recurrence or distant metastasis to be able provide further treatment of curative intent early. There is also the possibility that neuro-endocrine tumours of testis had so far been under-reported due to mis diagnosis of the tumour upon pathology examination of the testicular tumour or the correct set of monoclonal and polyclonal antibodies had not been utilized in the immunohistochemistry study assessment of the tumours. It would be advised that all clinicians and pathologists globally should have a high index of suspicion for a neuro-endocrine tumour of testis in order to establish prompt diagnosis of the tumour and to provide appropriate assessment, treatment and follow-up of all their patients.