736 Spontaneous Adenosquamous Carcinoma of the Prostate, a Case Report

Spontaneous adenosquamous carcinoma of the prostate is a rare and aggressive subtype of prostate cancer with no well-established treatment guidelines. A 63-year-old man presented with chief complaints involving the lower urinary tract and bowel. He complained of urgency urinary incontinence, frequency, and hematuria. He reported fecal urgency with hematochezia and no history of constipation. He had scrotal and penile pain with erectile dysfunction. He did not report any history of low back pain or lower limb paresthesia. He had no significant medical or surgical history. On clinical examination, the prostate was enlarged, non-tender with a palpable nodule and a TRUS volume of 35 grams. The serum PSA was 18.9 ng/dl. Multiparametric MRI of the prostate was done with instillation of a rectal gel given both his lower urinary tract and bowel symptoms. It showed an enlarged prostate with irregular prostatic outlines, heterogenous signals in all sequences, a prostatic cyst and a preserved recto-prostatic plane. A systematic trans-rectal ultrasound guided biopsy of the prostate showed a Gleason grade 5 + 5 in all cores, with glandular features on < 10% and squamous features in > 90%. There were widespread bone metastases with no visceral metastases. We initiated androgen deprivation therapy with Goserelin 10.8 mg pending evaluation for docetaxel chemotherapy. The patient had a rapid downhill clinical decline and died 6 months after the diagnosis and initiation of Goserelin. This case illustrates the aggressive nature of adenosquamous carcinoma and its poor response to hormone ablation therapy.