Tesis

Akurasi Diagnostik Pemeriksaan Imunositokimia Special AT- rich sequence-binding protein 2 (SATB2) pada Blok Sel dalam Penegakan Diagnosis Osteosarkoma = Diagnostic accuracy of SATB2 Immunocytochemistry Examination in Cell-Blocks in Diagnosis of Osteosarcoma.

Latar Belakang: Osteosarkoma (OS) merupakan tumor ganas tulang primer yang paling sering ditemukan. OS memiliki karakteristik pertumbuhan lokal yang agresif dan penyebaran sistemik secara hematogen yang sangat cepat. Diagnosis yang cepat dan tepat diperlukan sebagai dasar pemberian tata laksana. Diagnosis OS terkadang sulit ditegakkan dari sediaan sitopatologik dikarenakan matriks osteoid yang minimal. Special AT-rich sequence–binding protein 2 (SATB2) merupakan suatu matriks protein inti sel yang mengatur diferensiasi osteoblas. Pemeriksaan imunositokimia SATB2 pada blok sel merupakan pemeriksaan alternatif yang dapat dipilih karena tidak invasif dan memberikan hasil yang lebih cepat. Penelitian ini bertujuan untuk menilai akurasi pemeriksaan imunositokimia SATB2 pada blok sel untuk menegakan diagnosis OS di RSCM. Metode: Penelitian ini merupakan uji diagnostik dengan desain potong lintang. Sampel penelitian terdiri atas 35 kasus tumor tulang yang telah didiagnosis berdasarkan triple diagosis pada clinico-pathological conference (CPC). Seluruh kasus dipulas menggunakan rabbit monoclonal antibody SATB2. Penilaian imunoekspresi SATB2 dilakukan secara tersamar dan dianalisis dengan tabel 2x2 untuk mengetahui nilai diagnostiknya pada blok sel. Hasil: SATB2 terekspresi positif pada 80,9% kasus OS dan 33,3% kasus giant cell tumor of bone. SATB2 terekspresi negatif pada seluruh kasus kondroblastoma, sarkoma Ewing, synovial sarcoma, limfoma maligna nonHodgkin dan metastatic bone disease. Sensitivitas, spesifisitas, NDP, NDN, RKP, RKN dan akurasi yang didapat adalah 80,9%, 85,7%, 89,4%, 75%, 5,66, 0,22 dan 82,8%. Kesimpulan: Pemeriksaan imunositokimia SATB2 pada sediaan blok sel memiliki nilai diagnostik yang baik, namun tetap perlu dikorelasikan dengan usia, lokasi, temuan klinis serta gambaran radiologik.
Kata kunci: osteosarkoma, SATB2, diagnosis, imunositokimia, blok sel, akurasi.


Background: Osteosarcoma (OS) is the most common primary malignant bone tumor.OS is characterized by aggressive local growth and rapid systemic hematogenous spread. Prompt and precise diagnosis is needed as the basis for management. The diagnosis of OS is sometimes difficult to establish from cytopathological preparations due to minimal formation of osteoid matrix. Special AT-rich sequence–binding protein 2 (SATB2) is a nuclear protein matrix that regulates osteoblast differentiation. SATB2 immunocytochemistry examination on cell-block preparations is an alternative examination that can be chosen because it is not invasive and provides faster results. This study aims to assess the accuracy of SATB2 immunocytochemistry examination on cell-blocks to establish the diagnosis of OS in RSCM. Methods: This study is a diagnostic test with a cross-sectional design. The study sample consisted of 35 cases of bone tumors that had been diagnosed based on triple diagnosis at the clinico-pathological conference (CPC). All cases were stained with rabbit monoclonal antibody SATB2. The assessment of SATB2 expression was carried out blinding and was analyzed with 2x2 table to determine the diagnostic values in cell-block preparations. Results: SATB2 was positively expressed in 80.9% of OS cases and 33.3% of giant cell tumor of bone cases. SATB2 was negatively expressed in all of chondroblastoma cases, Ewing's sarcoma, synovial sarcoma, non-Hodgkin's malignant lymphoma and metastatic bone disease. The sensitivity, specificity, PPV, NPV, PLR, NLR and accuracy obtained were 80.9%, 85.7%, 89.4%, 75%, 5.66, 0.22 and 82.8%. Conclusion: SATB2 immunocytochemistry examination in cell-block preparations has good diagnostic value, but still needs to be correlated with age, location, clinical findings and radiological features.
Keywords: osteosarcoma, SATB2, diagnosis, immunocytochemistry. cell-block, accuracy.