von hippel  lindau ( vhl ) disease is a rare inherited condition affecting 1 in 36 000 births and is associated with the development of various multi - system tumours , including haemangioblastomas , phaeochromocytomas , renal cell carcinomas , endolymphatic sac tumours and papillary cystadenomas of the epididymis ( in men ) and broad uterine ligament ( in women ) . although the association between vhl and primary epididymal papillary cystadenomas is well known , there is extremely limited information about its malignant counterpart ( i.e. papillary cystadenocarcinomas ) with only a few cases reported in the literature [ 26 ] . the few case reports available have not been associated with vhl disease . as a result , there is also limited information regarding their optimal long - term management . we present the first reported case of a 43-year - old gentleman with vhl disease presenting with azoospermia and subsequently diagnosed with a primary epididymal papillary cystadenocarcinoma , infiltrating the spermatic cord and accompanied by a metastatic deposit in the right testis . the patient was ultimately managed by a combination of radical orchidectomy and onco - microtese . a 43-year - old gentleman with known vhl disease and a history of multiple renal carcinomas presented with primary infertility and non - obstructive azoospermia . on examination , he had an atrophic left testis ( secondary to a previous orchidopexy for cryptorchidism ) and a firm mass in the right epididymis . he was referred for testicular sperm extraction . at the time of surgical sperm retrieval , a biopsy was taken from the epididymal mass , which was reported as a cystadenocarcinoma . a further biopsy was taken of a mass incidentally noted in the upper pole of the right testis , which on histology was suggestive of a metastatic deposit of renal cell carcinoma . an orchidectomy was advised , but declined by the patient as he was keen to start a family . after successfully having a child via in vitro fertilisation  ( ivf ) treatment , he re - attended the urology department for definitive management of his epididymal and testicular tumours . he was asymptomatic and clinical examination revealed a palpable mass in the head of the epididymis measuring  ~1.5 cm . a separate small mass was also palpable in the upper pole of the right testis . blood tests revealed normal testicular tumour markers ( -fetoprotein , -human chorionic gonadotrophin and lactate dehydrogenase ) . follicle stimulating hormone and leutenizing hormone levels were 36 and 13 miu / ml respectively , with a testosterone level of 12.2 nmol / l . preoperatively , the optimal management strategy of his testicular and paratesticular lesions was complicated given the rarity of the case coupled with the challenge of multiple issues including : 
 future fertility preservation.atrophic , previously undescended , contralateral testis.borderline testosterone levels.propensity to develop further tumours on a background of vhl disease . initially , a partial orchidectomy was considered to preserve future fertility . however , after review at the multidisciplinary team ( mdt ) meeting , it was felt that a radical orchidectomy was the safest oncologocial management option and was agreed by the patient . this was performed via an inguinal approach and an onco - microtese ( microsurgical testicular sperm extraction in azoospermic cancer patients performed once the testicle has been removed ) was carried out to allow for future family planning . isolated areas of dilated tubules were retrieved under 20 magnification with viable sperm cryopreserved for future ivf . subsequent histological review revealed a multinodular tumour in the head and body of the epididymis , which exhibited varying architectural patterns . in some areas , the tumour resembled that of a classical papillary cystadenoma with papillary structures projecting into cystic spaces lined by cuboidal to columnar cells with pale eosinophilic to clear cytoplasm . however , in other areas , the tumour was composed of cystic as well as solid sheets of polygonal cells with clear cytoplasm . there was also a separate deposit in the upper pole of the testis , which was composed of cystic spaces filled with eosinophilic secretions and lined by polygonal cells with clear cytoplasm . based on the immunohistochemical findings , it was felt that the intratesticular tumour deposit most likely represented a metastasis from the papillary cystadenocarcinoma of the epididymis ( figs 1 and 2 ) . the epididymal tumour resembled that of a classical papillary cystadenoma ( 4 magnification ) . figure 2:histology of separate tumour deposit in testis composed of cystic spaces filled with eosinophilic secretions and lined by polygonal cells with clear cytoplasm ( 4 magnification ) . histology of epididymal tumour showing varying architectural patterns . in some areas , the epididymal tumour resembled that of a classical papillary cystadenoma ( 4 magnification ) . histology of separate tumour deposit in testis composed of cystic spaces filled with eosinophilic secretions and lined by polygonal cells with clear cytoplasm ( 4 magnification ) . given the unusual nature of the case , the unknown prognosis of papillary cystadenocarcinomas and the lack of established treatment protocols post - orchidectomy , an mdt decision of close clinical surveillance with regular follow - up was made . papillary cystadenomas of the epididymis are known to occur in association with vhl disease . however , the development of a papillary cystadenocarcinoma , its malignant counterpart , is incredibly rare . there is a single case report , which has documented metastases from such tumours to the paraureteral region . however , metastasis to the testis has not been previously reported in the available published literature . the presentation on a background of infertility and atrophic undescended contralateral testis raises further dilemmas in management . surgical debulking remains as the cornerstone for the treatment of primary malignant epididymal tumours either via partial or radical orchidectomy . a radical orchidectomy was considered to be the optimal treatment in view of the nature and location of his tumour , but the limited functional potential of his contralateral atrophic testis made his management more challenging . in this case , fertility preservation was paramount to the patient . combining his radical orchidectomy with a simultaneous surgical sperm retrieval using an onco - microtese allowed safe oncological management and optimal fertility preservation . referral to specialist units with expertise in performing onco - microtese is important in such difficult cases . written consent was obtained from the patient for publication of this case report and the accompanying images .