Outcomes and predictors of malignancy in radiologically non-adenomatous adrenal lesions: a retrospective study

Abstract

Aims: To compare the clinical, radiological, functional, and pathological characteristics of radiologically diagnosed adrenal adenomas versus non-adenomatous lesions and to identify predictors of malignancy and clinical significance among the nonadenomatous group. Methods: This retrospective study included 63 adult patients who underwent adrenalectomy between January 2015 and December 2024. Patients were classified based on preoperative computed tomography (CT) and/or magnetic resonance imaging (MRI) reports as having either radiologically suspected adrenal adenoma or non-adenomatous lesions. Clinical features, comorbidities, hormonal function, imaging characteristics, and histopathological outcomes were compared between the two groups. Logistic regression analysis was performed within the non-adenomatous group to identify independent predictors of malignancy and clinical relevance. ROC curve analysis was used to assess the diagnostic utility of tumor size. Results: Of the 63 patients, 29 (46.0%) were classified as adrenal adenomas and 34 (54.0%) as non-adenomatous lesions. Tumor size was significantly smaller in the adenoma group (mean 27.1±6.8 mm vs. 48.5±13.7 mm, p<0.001). Functional tumors were more prevalent in the adenoma group (93.1% vs. 41.2%, p<0.001). Malignancy (adrenocortical carcinoma and metastasis) was observed exclusively in the non-adenomatous group. Within this group, functional lesions were independently associated with malignancy (p=0.019, OR=8.95). ROC analysis showed moderate diagnostic value of tumor size for predicting malignancy (AUC=0.648, 95% CI: 0.372–0.924). Histopathological confirmation showed perfect concordance in the adenoma group (positive predictive value 100%). The adenoma group had higher rates of hypertension (p=0.013) and coronary artery disease (p=0.012). Conclusion: Radiologically non-adenomatous adrenal lesions are more likely to be malignant than radiologically diagnosed adenomas. Tumor size and functional status can aid in malignancy prediction within this subgroup. Radiologic classification offers high specificity, particularly for adenomas, and may guide preoperative risk stratification.

Keywords

• Adrenalectomy
• adrenal adenoma
• non-adenomatous adrenal lesion
• malignancy risk
• histopathology

Radyolojik olarak adenom dışı değerlendirilen adrenal lezyonlarda malignite sonuçları ve öngördürücü faktörler

Abstract

Amaç: Radyolojik olarak adenom tanısı almış adrenal lezyonlar ile adenom dışı lezyonların klinik, radyolojik, fonksiyonel ve patolojik özelliklerini karşılaştırmak; ayrıca adenom dışı grupta malignite ve klinik olarak anlamlı lezyonları öngören faktörleri belirlemektir. Yöntemler: Bu retrospektif çalışmaya Ocak 2015 ile Aralık 2024 tarihleri arasında adrenalektomi uygulanmış 63 erişkin hasta dahil edilmiştir. Hastalar, preoperatif BT ve/veya MR raporlarına göre radyolojik olarak adenom veya adenom dışı adrenal lezyonlar şeklinde sınıflandırılmıştır. Klinik özellikler, eşlik eden hastalıklar, hormonal fonksiyon, görüntüleme bulguları ve histopatolojik sonuçlar iki grup arasında karşılaştırılmıştır. Adenom dışı grupta malignite ve klinik olarak anlamlı lezyonları öngören bağımsız faktörleri belirlemek için lojistik regresyon analizi uygulanmıştır. Tümör boyutunun tanısal değerini değerlendirmek amacıyla ROC eğrisi analizi yapılmıştır. Bulgular: Toplam 63 hastanın 29’u (%46.0) adenom, 34’ü (%54.0) adenom dışı lezyon olarak sınıflandırılmıştır. Tümör boyutu adenom grubunda anlamlı derecede daha küçüktür (ortalama 27.1 ± 6.8 mm vs. 48.5 ± 13.7 mm, p<0.001). Fonksiyonel tümörler adenom grubunda daha sık görülmüştür (%93.1 vs. %41.2, p<0.001). Malignite (adrenokortikal karsinom ve metastaz) yalnızca adenom dışı grupta saptanmıştır. Bu grup içinde, fonksiyonel lezyonlar malignite ile bağımsız olarak ilişkili bulunmuştur (p=0.019, OR=8.95). ROC analizi, tümör boyutunun maligniteyi öngörmede orta düzeyde tanısal değere sahip olduğunu göstermiştir (AUC=0.648, %95 GA: 0.372–0.924). Adenom grubunda histopatolojik doğrulama tam uyum göstermiştir (pozitif prediktif değer %100). Hipertansiyon (p=0.013) ve koroner arter hastalığı (p=0.012) adenom grubunda daha yüksek oranlarda gözlenmiştir. Sonuç: Radyolojik olarak adenom dışı değerlendirilen adrenal lezyonlar, adenomlara kıyasla malignite açısından daha yüksek risk taşımaktadır. Bu grupta tümör boyutu ve fonksiyonel durum, malignite öngörüsünde yardımcı olabilir. Radyolojik sınıflama, özellikle adenomlar için yüksek özgüllük sunmakta olup preoperatif risk sınıflandırmasında yol gösterici olabilir.

Keywords

• adrenalektomi
• adrenal adenom
• adenom dışı lezyonlar
• malignite riski
• histopatoloji

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