Clinical Usefulness of Plasma Chromogranin A in Pancreatic Neuroendocrine Neoplasm

Chromogranin A (CgA) is widely used as an immunohistochemical marker of neuroendocrine neoplasms and has been measurable in plasma of patients. We assessed the clinical role of plasma CgA in diagnosing pancreatic neuroendocrine neoplasm (PNEN). CgA was checked in 44 patients with pancreatic mass who underwent surgical resection from 2009 through 2011. The cutoff value for diagnosing PNEN and the relationships between CgA and clinicopathologic variables were analyzed. Twenty-six patients were PNENs and 18 patients were other pancreatic disorders. ROC analysis showed a cutoff of 60.7 ng/mL with 77% sensitivity and 56% specificity, and the area under the curve (AUC) was 0.679. Among PNEN group, the sensitivity and specificity of diagnosing metastasis were 100% and 90% respectively when CgA cutoff was 156.5 ng/mL. The AUC was 0.958. High Ki-67 index (160.8 vs 62.1 ng/mL, P = 0.001) and mitotic count (173.5 vs 74.6 ng/mL, P = 0.044) were significantly correlated with plasma CgA, but the tumor size was not. In conclusion, CgA has a little value in diagnosing PNEN. However, the high level of CgA (more than 156.5 ng/mL) can predict the metastasis. Also, plasma CgA level correlates with Ki-67 index and mitotic count which represents prognosis of PNENs.

Diferenciación neuroendocrina y marcadores de proliferación celular en adenocarcinoma de próstata en un grupo de casos con antígeno prostático específico normal vs elevado / Neuroendocrine differentiation and markers of cell proliferation in a group of patients with prostate adenocarcinoma and normal or high serum prostate-specific antigen levels

Objetivo. Investigar la población de células neuroendocrinas y sus características morfológicas en pacientes con cáncer de próstata y antígeno sérico normal versus antígeno sérico elevado. Material y métodos. En 13 años se identificaron 372 casos de cáncer de próstata de los cuales 19 (5.1%) con antígeno sérico normal (Grupo I). Se seleccionaron 16 grupos controles con antígeno sérico elevado y características histopatológicas similares (Grupo II). Se evaluaron porcentaje de necrosis tumoral, invasión vascular y perineural, inmunohistoquímica: sinaptofisina, enolasa neuroespecífica, antígeno prostático específico, Ki-67 y p53. Resultados. En el grupo I, se obtuvieron 61 % de casos positivos para antígeno tisular, 28.6 % sinaptofisina, 7.1 % para enolasa neuroespecífica, 50 % para p53 y 78.6 % para Ki-67. En el grupo II, los resultados fueron: sinaptofisina 13.3%, enolasa-neuroespecífica 26.6%, antígeno tisular 93%, p53 46.6% y Ki-67 66.7%. Con punto de corte de antígeno tisular expresado en < 80% de células neoplásicas, en el grupo I se encontraron 69.2% de casos, y en el grupo II 21.4% (p = 0.02). Conclusiones. El único dato histológico que mostró diferencia significativa fue la expresión tisular de antígeno prostático específico en < 80% de las células neoplásicas en el grupo I. Se asoció el incremento de las células neuroendocrinas con el menor número de células productoras de antígeno tisular; esta situación podría ser más visible al estudiar un mayor número de pacientes con características semejantes.

OBJECTIVE: Study the morphologic characteristics of neuroendocrine cells in prostate cancer with normal versus elevated prostate specific antigen (PSA). MATERIALS AND METHODS: 372 cases of prostate cancer were identified during a 13 year period, of which 19 displayed normal PSA (group I). Sixteen controls with elevated PSA and similar histopathological characteristics (group II) were included. We studied the degree of tumor necrosis, vascular and perineural invasion. Synaptophysin (SP), neuron specific enolase (NSE), PSA, Ki-67 and p53 inmunoreactivity were also analyzed. RESULTS: Group I positive findings were 61% PSA, 28.6% SP. 7.1% NSE, 50%p53, and 78.6% Ki-67. Group II positive findings were 93% PSA, 13.3% SP, 26.6% NSE 46.6% p53, and 66.7% Ki-67. When we used a <80% cut off point for PSA immunoreactivity in tumor cells, 69.2% of group I and 21.4% of group II were found. CONCLUSIONS: The sole histopathological finding that showed statistical significance was the tissular expression of the specific prostatic antigen in 80% of neoplasic cells in group I. The increase of neuroendocrine cells was associated with a smaller number of tissular antigen producing cells, a finding that could be more apparent if we were to study a larger sample size.