RESUMEN
Ga-PSMA PET/CT has become a well-established imaging modality to detect prostate cancer (PCa) metastases in biochemical recurrence. Despite its claimed specificity for PCa, Ga-PSMA uptake in tissues unrelated to PCa, particularly in the neovascular tissue of other cancers, has been reported in numerous studies. A 73-year-old man underwent Ga-PSMA PET/CT for biochemical recurrence of PCa 7 years after radical prostatectomy. The Ga-PSMA PET/CT showed 1 lesion with PSMA uptake in the distal left ureter. Histology revealed a low-grade noninvasive papillary urothelial carcinoma. By immunohistochemistry, PSMA expression was observed in the neoplastic urothelial cells and in the vessels of the papillary structures.
Asunto(s)
Antígenos de Superficie/metabolismo , Regulación Neoplásica de la Expresión Génica , Glutamato Carboxipeptidasa II/metabolismo , Glicoproteínas de Membrana/metabolismo , Compuestos Organometálicos/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones , Uréter/metabolismo , Neoplasias Urológicas/diagnóstico por imagen , Neoplasias Urológicas/metabolismo , Anciano , Transporte Biológico , Isótopos de Galio , Radioisótopos de Galio , Humanos , Ligandos , Masculino , Prostatectomía , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Recurrencia , Neoplasias Urológicas/secundarioRESUMEN
Immunohistochemical (IHC) quantification of estrogen receptor-α (ER) is used for assessment of treatment regimen in breast cancer. Different ER IHC assays may produce diverging results, because of different antibody clones, protocols, and stainer platforms. Objective tissue-based techniques to assess sensitivity and specificity of IHC assays are therefore needed. We tested the usability of ER mRNA-in situ hybridization (mRNA-ISH) in comparison with assays based on clones SP1 and 6F11. We selected 56 archival specimens according to their reported ER IHC positivity, representing a wide spectrum from negative to strongly positive cases. The specimens were used to prepare 4 TMAs with 112 cores. Serial sections of each TMA were stained for ER and pan-cytokeratin (PCK) by IHC and ESR1 (ER gene) by mRNA-ISH. Digital image analysis (DIA) was used to determine ER IHC H-score. ESR1 mRNA-ISH was scored both manually and by DIA. DIA showed a nonlinear correlation between IHC and ESR1 mRNA-ISH with R-values of 0.80 and 0.78 for the ER antibody clones SP1 and 6F11, respectively. Comparison of manual mRNA-ISH scoring categories and SP1 and 6F11 IHC H-scores showed a highly significant relationship (P<0.001). In conclusion, the study showed good correlation between mRNA-ISH and IHC, suggesting that mRNA-ISH can be a valuable tool in the assessment of the sensitivity and specificity of ER IHC assays.