Every so often, it is a good idea to remind ourselves just how little we really understand about all the possible forms of prostate cancer.
A recent case report by We et al. in the Journal of Andrology decribes a case of metastatic prostate cancer in a 78-year-old Chinese male, diagnosed in early 2010 with Gleason 10 disease and a serum PSA level of > 1,100 ng/ml but no visible evidence of bone metastasis on a bone scan at the time of diagnosis.
Initial therapy of the patient (bilateral orchiectomy and oral bicalutamide) appeared to be effective. His PSA had dropped to 9.8 ng/ml by March 2010 and he exhibited no other symptoms of progressive prostate cancer on follow-up. However, in November 2010 he re-presented with clear evidence of priapism (an erection that would not go down). His penis was erect, swollen, and extremely hard. However, his PSA was only 0.09 ng/ml.
After discussion, the patient elected to have a radical penectomy because of a strong desire for relief from the severe pain associated with priapism. Post-surgical pathology of the penis showed undifferentiated adenocarcinoma growing in the corpora cavernosa … but these metastatic cells were not expressing PSA. The patient chose further conservative hormonal therapy without any radiation therapy or chemotherapy.
In March 2011, the patient presented at the clinic once again, this time with multiple, subcutaneous, non-tender nodules on the lower part of his right leg. His serum PSA level was still low, at 0.264 ng/ml. However, biopsy of the nodules clearly showed the presence of metastatic adenocarcinoma.
The patient refused further active treatment and died from progressive disease 3 months after his initial presentation with skin metastases.
While the vast majority of men with metastatic prostate cancers follow a relatively predictable course over time — including the initial and progressive evidence of metastases in the spine, the pelvis, the ribcage, and then the arms and legs — it is clear that there are other, very different ways that prostate cancer can metastasize in some patients. Support group leaders and other prostate cancer educators should always be conscious that such “exceptions” to the general rule need to be watched for and appropriately referred for palliative forms of care.