Small-cell carcinoma of the prostate with negative CD56,NSE,Syn,and CgA indicators:A case report

BACKGROUND Small-cell carcinoma of the prostate(SCCP)is a clinically rare malignant tumor,accounting for<1%of all prostate tumors.However,negativity for all SCCP neuroendocrine markers is rare.Herein,we report a case of SCCP with completely negative neuroendocrine markers and explore its clinicopathologic features,thus improving the understanding of its clinical diagnosis and management.CASE SUMMARY We report the case of a 48-year-old patient with SCCP negative for common sensitive neuroendocrine-staining indicators.Dysuria was the first symptom,and rectal examination revealed a hard prostate,palpable nodules,diffuse prostate enlargement,no pressure pain,no blood staining in the finger sleeve,1.33 ng/mL total prostate-specific antigen level,and a free-to-total prostate-specific antigen ratio of 0.21 ng/mL.Ultrasound suggested a prostate size of 5.3 cm×5.8 cm×5.6 cm,and magnetic resonance imaging suggested prostate cancer.The lower posterior bladder wall,rectal mesentery,and bilateral seminal vesicles were invaded,with multiple lymph node metastases in the pelvis.A whole-body bone scan suggested an abnormally active multiple bone metabolism and possible bone metastases.Head and lungs computed tomography revealed no significant nodal shadow.Following a pathological diagnosis of SCCP after a prostate puncture,with negative indicators of common sensitive neuroendocrine staining,chemotherapy was administered;the patient died 4-5 mo after SCCP diagnosis.CONCLUSION SCCP is a rare disease characterized by atypical clinical symptoms,limited treatment options,a short survival period,and a poor prognosis.