| 4. Immunostaining is a valuable method for autopsy diagnosis: 2 case reports |
Yuki Abe1）, Takehiko Murase1）, Kuniko Abe2）, Takahiro Umehara1）, Hiromi Yamashita3）, Yoshinori. Shibaike1）, Kazuya. Ikematsu1）
1) Department of Forensic pathology and Science, Graduate school of Biomedical sciences, Nagasaki University school of medicine, Nagasaki , Japan
2) Department of Pathology, Graduate school of Biomedical sciences, Nagasaki University school of medicine, Nagasaki, Japan
3) Center for Forensic Pathology and Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan |
Introduction:
Immunostaining is not commonly used by Japanese forensic pathologists; however, we can detect specific proteins and easily identify tissue components and hormone secretions with immunostaining. We also consider immunostaining to be useful for autopsy diagnosis. Recently, we had 2 cases where immunostaining was a critical factor for the end diagnosis.
Case 1:
An autopsy was performed on a man in his 80’s, a giant hematoma along the longitudinal fissure and an extensive subarachnoid hemorrhage were identified. The hematoma had evidence of cell proliferation with pale eosinophilic cytoplasm and homogeneous circular nuclei in the hematoxylin-eosin staining (HE staining). We suspected pituitary adenoma; however, we could not determine the subtype of pituitary adenoma at that time. It has been suggested in the literature that postmortem blood tests would not be insightful due to the fact that any change in hormone kinetics could happen in this case, so we performed immunostaining to detect hormone secretions. The result showed negative for GH, ACTH, TSH and PRL. This finding allowed us to diagnose the lesion as pituitary apoplexy caused by non-functional pituitary adenoma.
Case 2:
An autopsy was performed on a man in his 50’s and a hematoma-like space occupying lesion (SOL) at his left cerebellopontine angle, which seemed to be pressing the pons, was detected. In low magnification of HE-staining, we found luminal structure-like findings in various sizes, which could suggest the possibility of polycystic change or vascular malformation. In high magnification of HE-staining, we detected spindle shaped cells, which can be generally seen in schwannoma and its reactive changes (e.g. inflammation, fibrosis, gliosis etc.). Since we could not determine whether it was schwannoma or cerebral arteriovenous malformation (AVM), we performed immunostaining with anti-CD31 and anti-S- 100 protein antibodies. Immunostaining was positive for S-100 protein and negative for CD31. The results allowed us to diagnose the lesion as schwannoma with polycystic change.
Discussion and conclusion:
We often have difficulty checking which hormone is secreted by a tumor with postmortem blood test, this is because blood hormone levels are dramatically affected by various factors and it is difficult to evaluate the correct hormone levels prior to death. Also, as in case 2, it is difficult to diagnose lesions with only HE staining when the lesions have been modified. In summary, we have concluded that immunostaining, which can easily detect hormone secretions and tissue components, is a valuable method for autopsy diagnosis. |
|
