Methods matter - Tailoring SARS-CoV-2 antibody targets to vaccination status.

Individuals who have been vaccinated for COVID19 should have IgG antibody in response to the specific antigen that is the target in the vaccine development. There are several options for targeted COVID19 antigen, but most manufacturers have focused on the spike protein. Using our understanding of the targeted antigen for vaccine development, we can develop testing algorithmic scheme for anti-spike and anti-nucleocapsid antibody assays to aid delineation of infection versus vaccination in our patient population. Clear communication from laboratories specifying the specific SARS-CoV-2 antibodies (i.e., anti-spike, anti-nucleocapsid, or both) in their antibody tests at both the ordering and reporting levels will play crucial role in the development of this approach and is essential to avoid potential provider/patient confusion in the interpretation of serologic testing.

Pseudoangiomatous stromal hyperplasia of the prostate: report of an unprecedented entity in prostate pathology.

Pseudoangiomatous stromal hyperplasia is a benign entity of the breast. It is histologically characterized by open, slit-like spaces lined by spindle cells of myofibroblast/fibroblast differentiation in a dense collagenous stroma. Although pseudoangiomatous stromal hyperplasia has been reported in ectopic breast tissue in anogenital mammary-like glands, it has not been previously reported in non-breast tissues. This includes prostatic tissue, which shares similar histology and pathology with the breast. Herein, we report the first case of prostatic pseudoangiomatous stromal hyperplasia based on histological, immunohistochemical, and electron microscopic findings. The patient was a 74-year-old man with a history of benign prostatic hyperplasia who presented with severe urinary retention and underwent transurethral resection of the prostate. In addition to benign prostatic hyperplasia, the prostate showed areas of irregular spaces lined occasionally by flattened spindle cells in a background of fibrocollagenous stroma. Immunohistochemically, these cells were diffusely positive for vimentin and negative for CD31, CD34, ERG, pancytokeratin, SMA, and D2-40. Electron microscopic findings also showed some cells with fibroblastic features lining these spaces. Given these findings, we postulated that pseudoangiomatous stromal hyperplasia of the prostate has some cells of fibroblastic lineage. Contrary to its breast counterpart where lining cells demonstrate diffusely and strongly positive staining for CD34 and PR, this prostate case showed negative staining for CD34 and PR. These findings indicate potential differences in the histogenesis of prostatic and breast pseudoangiomatous stromal hyperplasia.