case_images: PMC10601763_01
case_images: Histopathological findings of the present case. Prostate biopsy revealed a mixture of small-cell carcinoma (a) and acinar (b) components of the prostate. Hematoxylin and eosin staining. c Immunohistochemistry (IHC) for synaptophysin in the initial prostate biopsy. d Prostate tissue resected using transurethral resection (TUR) of the prostate after castration-resistant prostate cancer. e IHC for synaptophysin in the TUR specimen. f Liver biopsy specimen after CRPC.
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case_images: F1
case_images: Transrectal prostate biopsy revealed SCPC/NEPC in two-thirds of the cancerous regions of the prostate, and acinar adenocarcinoma in the residual one-third of the regions (Fig. 1a-c), which as diagnosed a mixture of SCPC and acinar adenocarcinoma. The pathological diagnoses of prostate (Fig. 1d, e) and liver tissues (Fig. 1f) were small-cell neuroendocrine carcinoma with positive expression of neuroendocrine markers (including chromogranin A and synaptophysin), suggesting that the primary region of the metastases was the prostate.
case_images: Longitudinal changes in radiographic findings before and after (4 months) chemotherapy with carboplatin and etoposide or a poly ADP-ribose polymerase inhibitor. CE, carboplatin and etoposide; PARPi, poly ADP-ribose polymerase inhibitor.
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case_images: F2
case_images: Contrast-enhanced computed tomography revealed multiple lung, liver, and lymph node metastases, aggressive progression of bone metastasis, and an enlarged prostate (Fig. 2). AUC 5, day 1; etoposide, 80 mg/mL, days 1-3) every 4 weeks. After four cycles of this chemotherapy, the metastatic regions regressed markedly (Fig. 2). NSE levels decreased to 0.330 ng/mL (96.9% decrease relative to the level detected before CE administration) and 8.8 ng/mL (91.6% decrease), respectively (Fig. 3). Nevertheless, 2 months after the completion of the chemotherapy, elevation of tumor marker levels and re-growth of lung and lymph node metastases were observed (Fig. 2, 3).
case_images: Clinical patterns with changes in tumor markers and treatment responses. CBDCA, carboplatin; VP16, etoposide; ADT, androgen-deprivation therapy; PR, partial response; SD, stable disease; PD, progressive disease.
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case_images: F3
case_images: The time course of the treatment is summarized in Figure 3. The patient was treated with combination chemotherapy with carboplatin plus etoposide (CE; CBDCA, NSE levels decreased to 0.330 ng/mL (96.9% decrease relative to the level detected before CE administration) and 8.8 ng/mL (91.6% decrease), respectively (Fig. 3). Nevertheless, 2 months after the completion of the chemotherapy, elevation of tumor marker levels and re-growth of lung and lymph node metastases were observed (Fig. 2, 3).