M. G. DURAK, M. M. AKIN, M. Ş. CANDA, M. A. KOÇDOR, A. ÇÖMLEKÇİ, B. BİRLİK

Pathologic features, Ki-67 indices and melan-A expression in adrenal neoplasms

Amaç: Adrenokortikal neoplazm ile feokromositom ayırıcı tanısı zaman zaman oldukça güçlük göstermektedir. Son dönemde gelişen moleküler yöntemler umut verici olsa da, tanı verirken hala temel olarak tümörün histopatolojik ve immunhistokimyasal boyanma özellikleri dikkate alınmaktadır. Bu çalışmanın amacı, bölümümüzde adrenokortikal adenom/karsinom ve feokromositom olarak tanı almış olguların klinikopatolojik özelliklerini yeniden gözden geçirmektir. Yöntem ve Gereç: Dokuz Eylül Üniversitesi Patoloji Bölümü’nde, 1995 ile 2010 yılları arasında tanı alan 16 adrenokortikal neoplazm ile 3’ü bilateral yerleşimli olmak üzere 7 feokromositom olgusunun klinikopatolojik özellikleri yeniden gözden geçirildi. Tümörlü bloklara uygulanan Ki-67 ve melan-A immunhistokimyasal boyaları değerlendirildi. Bulgular: Adrenokortikal neoplazm olguları 25 ile 60 yaş arasında olup ortalama yaş 45’dir. Onaltı adrenokortikal neoplazm olgusunun 15’i adenom, 1’i karsinomdur. Adenom olgularının Ki-67 proliferasyon indeksi %0.2 ile %6.0 arasında olup ortalama Ki-67 proliferasyon indeksi %1.7’dir. Onbeş adenom olgusunun 4’ünde (%27) melan-A pozitifliği saptanmıştır. Tek kortikal karsinom olgusunda Ki-67 proliferasyon indeksi %20 olup melan-A negatif olarak izlenmiştir. Feokromositom olguları 28 ile 63 yaş arasında olup ortalama yaş 46’dır. Dört feokromositom olgusu benign, 2’si bilateral yerleşimli olan 3 olgu ise malign özelliktedir. Yedi feokromositom olgusuna ait toplam 10 tümörde Ki-67 proliferasyon indeksi %0.2 ile %20 arasında olup ortalama Ki-67 proliferasyon indeksi %3.3’tür, ve bu olguların hiçbirinde melan-A immunreaktivitesi görülmemiştir. Sonuç: Çalışmadaki olgu sayısı sınırlı olmakla birlikte, bulgular adrenal neoplazmlarda tümör biyolojisini saptamak için Ki-67 immunhistokimyasal boyasının rutin uygulamalarda yararlı olabileceğini göstermektedir. Ayrıca adrenokortikal tümörler ile feokromositom ayırıcı tanısında, immunhistokimyasal olarak melan-A pozitifliği kortikal orijini destekleyen bir bulgu olarak kullanılabilir.

Adrenal neoplazmlarda patolojik özellikler, Ki-67 proliferasyon indeksi ve melan-A ekspresyonu

Aim: Differential diagnosis of adrenocortical neoplasms and pheochromocytoma may occasionally be very difficult. Although recently developed molecular techniques are encouraging, histopathologic features and immunohistochemical markers are still the mainstay of diagnosis. The aim of this study is to re-evaluate the clinicopathologic features of our cases diagnosed as adrenocortical adenoma/carcinoma and pheochromocytoma. Material and Methods: Sixteen cases of adrenocortical neoplasm and 7 cases of pheochromocytoma, 3 of which were bilateral, diagnosed between 1995 and 2010 at Dokuz Eylül University Pathology Department were reviewed. The immunohistochemical staining of Ki-67 and melan-A were examined. Results: The mean age of the adrenocortical neoplasm cases was 45 years (range, 25-60). Fifteen of 16 adrenocortical neoplasms were cortical adenoma and 1 was cortical carcinoma. The mean Ki-67 proliferation index in the cortical adenoma cases was 1.7% (range, 0.2-6.0%). Four of the 15 adenoma cases (27%) were melan-A positive. In one cortical carcinoma case, the Ki-67 proliferation index was 20% and melan-A was negative. The mean age of the pheochromocytoma cases was 46 years (range, 28-63). Four pheochromocytoma cases were benign, whereas 3 cases, 2 of which were bilateral, had histopathologic features suggesting malignant behavior. The mean Ki-67 proliferation index of 10 pheochromocytomas from 7 cases was 3.3% (range, 0.2-20.0%), and none of these cases showed melan-A immunoreactivity. Conclusion: Although the number of patients is limited in this study, our findings suggest that Ki-67 immunohistochemical stain can be used in routine practice to determine tumor biology in adrenal neoplasms, and melan-A positivity may favor cortical origin in differential diagnosis of adrenocortical tumors and pheochromocytoma.

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