Presentation
Two years previously he had undergone radical prostatectomy for prostate adenocarcinoma.
Patient Data
Alveolated lung parenchyma shows a solitary deposit of metastatic prostate acinar adenocarcinoma, composed of cribriform and fused glands lined by mildly pleomorphic cuboidal/low columnar epithelium with prominent nucleoli and moderately abundant eosinophilic/pale cytoplasm. Scattered mitotic figures are present. The surrounding lung is unremarkable.
20x H&E: Subpleural nodule of adenocarcinoma causing pleural puckering.
20x H&E: Sharply circumscribed nodule of tumor in otherwise unremarkable lung.
40x H&E: Solid tumor with cribriform architecture. An entrapped bronchiole is present in the lower-left corner.
100x H&E: Adenocarcinoma suspicious for involvement of pleura.
200x H&E: Acinar-type architecture reminiscent of cribriform type architecture in prostate adenocarcinoma.
400x H&E: Cribriform architecture lined by epithelial cells showing moderate pleomorphism and prominent nucleoli.
Special staining for elastin to assess pleural involvement.
Confirmatory immunohistochemistry to determine the primary site of origin.
100x Verhoeff van Gieson: Tumor approaches elastica lamina of pleura.
200x Verhoeff van Gieson: Tumor is very close to but does not disrupt the elastica lamina.
100x PSA: Focal positive staining.
200x PSAP: Focal positive staining.
Case Discussion
Whilst undergoing imaging for another reason, a lesion was found in the right lower lung lobe. Video-assisted thoracoscopic surgery (VATS) was performed, and an excisional lung wedge biopsy performed, revealing a solitary tan sub-pleural mass ~2cm in size. Two years previously he had undergone radical prostatectomy for prostate adenocarcinoma.
Although having a documented history of Gleason score 7 prostate adenocarcinoma, and tumor morphology consistent with metastatic prostate adenocarcinoma, confirmatory immunohistochemistry studies are still required to be performed to determine the primary site of origin of the tumor deposit. Other stains performed included cytokeratins 7 and 20 and TTF-1.