A Caucasian man in his mid sixties presented with acute urinary retention. His prostate specific antigen (PSA) level was markedly raised at 97 ng/ml (N≤4.0 ng/ml), and on clinical examination he had a grossly enlarged benign-feeling prostate gland. Transrectal ultrasound scan (TRUS) showed a prostate volume of 145 ml with multiple hypo-echoic areas, indicating extensive cystic structures (), but on biopsy there was no evidence of adenocarcinoma. No further investigations were arranged at this stage. A trial without catheter was successful and the patient's lower urinary tract symptoms (LUTSs) were well-controlled with α-blockers; hence, transurethral prostatectomy was not offered. PSA was monitored closely and the patient was managed conservatively as he had multiple medical co-morbidities and had suffered a major cerebro-vascular accident. Therefore, he was deemed unsuitable for aggressive/radical surgical treatment.
(A,B) Transrectal ultrasound scan showing extensive cystic changes in the prostate.
TRUS and prostate biopsy were repeated 3 years later as the PSA had gradually risen to 192.8 ng/ml. TRUS showed the same cystic findings. Histopathological findings, which resembled those seen on previous biopsy, revealed large atypical stromal cells, some multinucleate, with plentiful mitoses, including bizarre forms. The cells were immunoreactive for vimentin, but they did not stain for PSA, cytokeratins or CD68 (a macrophage marker). Several long, flat, surfaces lined by normal looking epithelial and basal cells were also present but there was no evidence of cancer although occult prostatic carcinoma remained a possibility. Based on the histological appearances, a diagnosis of phyllodes tumour (likely non-PSA secreting) was suggested (). A CT scan confirmed the TRUS findings and showed a prostate volume of about 1175 ml. Bone scan was negative for metastases.
Histopathological section of prostatic tissue showing a bland epithelial surface with underlying bizarre stromal cells. H&E ×20 objective.
The patient was considered for radical cysto-prostatectomy based on the evidence of a non-metastatic locally advanced extensive lesion, which warranted surgical excision as the only means of disease control/cure. However, in view of the heightened risks associated with the procedure, he was deemed unfit for major extirpative surgery and as such, quite rightly, declined surgery.
Therefore, hormone treatment in the form of depot LHRH-a was started on account of his rising PSA to achieve androgen blockade.
The patient was re-admitted 4 months later with increasing LUTS and threatened urinary retention but neither a urethral nor a suprapubic catheter could be inserted because of the tumour's size. A CT scan showed a large (1300 ml) tumour filling the pelvis with the bladder lying anterior to the tumour and compressed between it and the anterior abdominal wall. There were areas of fluid, which could have represented cyst fluid, tumour necrosis or recent haematoma (). Catheterisation of the bladder failed because of the large tumour volume but the patient eventually managed to void spontaneously.
(A,B) CT scan showing large prostatic mass with tumour necrosis/haematoma.
There was no ultrasound evidence of obstructive uropathy but the patient went on to develop acute-on-chronic renal failure as a result of cast nephropathy secondary to recently diagnosed plasma cell (multiple) myeloma. He was also found to have a 4×3 cm right hilar lung mass, which occluded the upper lobe bronchus leading to collapse of the lobe. It was associated with several enlarged lymph nodes in the carinal, precaval and paratracheal groups. The appearances were suggestive of advanced bronchogenic carcinoma but could have been metastases from the phyllodes tumour although no bronchoscopy and biopsy was performed to ascertain the exact pathology. Hypercalcaemia was noted presumably related to the plasma cell myeloma.
The patient was unfit for surgical excision of the prostatic tumour and palliative hormone treatment was continued as it had managed to lower the PSA down to 3.0 ng/ml (from 192.8 ng/ml) in 4 months, although it had failed to achieve reduction in the size of the prostate, thereby suggesting presence of a non-PSA secreting phyllodes tumour.