Performa Diagnostik Densitas Asites pada Pemeriksaan Computed Tomography Scan Abdomen dengan Hasil Sitologi Asites sebagai Prediktor Derajat Keganasan Asites pada Pasien Keganasan Intra-Abdomen

Fradita Eka Sukardi, Dr. dr. Bambang Supriyadi, Sp. Rad., Subsp. MSK (K), MM.; dr. Anita Ekowati, Sp. Rad., Subsp. TR (K)

2025 | Tesis | S2 Kedokteran Klinik

Latar Belakang: Asites merupakan akumulasi cairan abnormal di rongga peritoneum yang dapat disebabkan oleh berbagai kondisi, termasuk keganasan intra-abdomen. Asites maligna berhubungan dengan prognosis buruk dan tata laksana kompleks. Sitologi cairan asites adalah standar emas diagnosis, tetapi sensitivitasnya terbatas dan bersifat invasif. Computed tomography (CT) scan abdomen non-kontras memungkinkan pengukuran densitas cairan asites secara kuantitatif, yang berpotensi membedakan asites maligna dari benigna.

Tujuan: Menilai performa diagnostik densitas asites pada CT scan abdomen non- kontras dengan sitologi sebagai standar rujukan, serta menentukan nilai cut-off untuk membedakan asites maligna dari benigna.

Metode: Penelitian ini merupakan studi uji diagnostik retrospektif terhadap 60 pasien keganasan intra-abdomen yang menjalani CT scan abdomen non-kontras dan sitologi asites di RSUP Dr. Sardjito Yogyakarta periode Januari 2023–Mei 2025. Densitas cairan asites diukur menggunakan region of interest (ROI) ? 1 cm² pada tiga area berbeda. Reliabilitas antar-pengamat dianalisis dengan intraclass correlation coefficient (ICC), sedangkan akurasi diagnostik dievaluasi menggunakan receiver operating characteristic (ROC).

Hasil: Rerata densitas asites maligna lebih tinggi dibandingkan asites benigna (15,0 HU vs. 8,8 HU; p < 0 xss=removed>

Kesimpulan: Densitas asites pada CT scan abdomen non-kontras memiliki akurasi baik untuk membedakan asites maligna dari benigna pada pasien keganasan intra- abdomen. Nilai cut-off ? 9,5 HU dapat digunakan sebagai prediktor sensitif dan layak dipertimbangkan sebagai parameter kuantitatif tambahan dalam praktik radiologi klinis.

Background: Ascites is an abnormal accumulation of fluid in the peritoneal cavity, caused by various conditions including intra-abdominal malignancy. Malignant ascites is associated with poor prognosis and complex management. Ascitic fluid cytology is the gold standard for diagnosis but has limited sensitivity and is invasive. Non-contrast abdominal computed tomography (CT) allows quantitative measurement of ascitic fluid density, potentially distinguishing malignant from benign ascites.

Objective: To evaluate the diagnostic performance of ascitic fluid density on non- contrast abdominal CT compared with cytology as the reference standard, and to determine the optimal cut-off value to differentiate malignant from benign ascites.

Methods: This retrospective diagnostic test study included 60 patients with intra- abdominal malignancies who underwent non-contrast abdominal CT and ascitic fluid cytology at Dr. Sardjito General Hospital, Yogyakarta, between January 2023 and May 2025. Ascitic fluid density was measured using a region of interest (ROI) ? 1 cm² in three different areas. Interobserver reliability was assessed using intraclass correlation coefficient (ICC), while diagnostic accuracy was analyzed with receiver operating characteristic (ROC) curve.

Results: Mean ascitic fluid density was significantly higher in malignant ascites compared with benign ascites (15.0 HU vs. 8.8 HU; p < 0 xss=removed>

Conclusion: Ascitic fluid density on non-contrast abdominal CT shows good accuracy for differentiating malignant from benign ascites in patients with intra- abdominal malignancies. A cut-off value of ? 9.5 HU can serve as a sensitive predictor and may be applied as an additional quantitative parameter in clinical radiology practice.

Kata Kunci : asites maligna, CT scan abdomen, densitas asites, sitologi, akurasi diagnostik