case_images: PMC10713708_01
case_images: Bone scan shows the patient developed multiple loci of metastasis in the lumbar vertebra, sacral vertebra and left pubis (A). The metastatic lesions response well to ADT (B). MR images show a soft tissue mass in the pelvis [(C), blue arrow], and the lesions partially regress after three cycles of chemotherapy [(D), blue arrow]. A brain MRI scan reveals multiple metastases [(E, F), blue arrow].
case_images: pore-29-1611343-g001.jpg
case_images: PMC10713708_01_pore-29-1611343-g001.jpg
case_images: F1
case_images: The bone scan images revealed multiple lesions in the lumbar vertebra, sacral vertebra and left pubis, consistent with metastases (Figure 1A). His serum PSA level remarkably reduced and the follow-up bone scan showed a reduction in metastatic lesions in May 2019 (Figure 1B). When he revisited our hospital in July 2022, the CT scan revealed a large soft tissue mass in the pelvis (Figure 1C). The pelvic mass responded well to treatment and partially regressed by the end of the third cycle in October 2022 (Figure 1D). In April 2023, multiple metastatic foci were discovered in the brain, confirming tumor progression (Figures 1E, F).
case_images: Histological examination and immunohistochemistry results. (A) The squamous component is composed of keratinized carcinoma nests with polygonal cells containing voluminous cytoplasm (Hematoxylin and eosin, x400). (B) P40 staining shows nuclear positivity for the squamous carcinoma cells (immunohistochemistry staining, x200). (C) The prostate adenocarcinoma displays a Gleason score of 5 with a solid pattern (Hematoxylin and eosin, x100). (D) The expression of prostate-specific marker NXK3.1 confirms the diagnosis (immunohistochemistry staining, x100). (E) Comparison of genes with high mutation frequencies between squamous cell carcinoma and adenocarcinoma.
case_images: pore-29-1611343-g002.jpg
case_images: PMC10713708_01_pore-29-1611343-g002.jpg
case_images: F2
case_images: The keratinizing SCC component was characterized by irregularly infiltrating cancer nests that exhibited notable keratin pearls at low magnification and pleomorphic polygonal cells containing abundant eosinophilic cytoplasm at high magnification (Figure 2A). The AC morphology demonstrated a high-grade prostate cancer, which was assigned a Gleason score of 5 + 4 = 9 (Figure 2C). NKX3.1 (clone EP356, Maixin Biotech), P40 (clone ZR8, Maixin Biotech), MLH1 (clone M1, ready to use, Ventana), PMS2 (clone MX061, 1:100, Maixin Biotech), MSH2 (clone A16-4, ready to use, Ventana), MSH6 (clone SP93, ready to use, Ventana) with positive and negative controls. The SCC was negative for PSA and NKX3.1, but positive for P40 (Figure 2B). In contrast, the adenocarcinoma component demonstrated diffuse positivity for prostate-specific marker NKX3.1 (Figure 2D). Notably, both components showed retained staining for the four mismatch repair proteins (MMR) (MLH1, MSH2, MSH6, and PMS2), referring to a status of MSI-L. The study also examined genes that had a high frequency of mutation. The SCC component showed differential mutant genes including HOXB7, POLR2G, ANKRD49, PFKFB1, KLRG1, OR5F1, and DPF2, when compared to the AC (Figure 2E).