Rare Solid Tumor of the Exocrine Pancreas: A Pictorial Review

Utility of CT to Differentiate Pancreatic Parenchymal Metastasis from Pancreatic Ductal Adenocarcinoma

Simple Summary

The purpose of this retrospective study was to report the computed tomography (CT) features of pancreatic parenchymal metastasis (PPM) and identify CT features that may help discriminate between PPM and PDAC. At multivariable analysis, well-defined margins (OR, 6.64; 95% CI: 1.47–29.93; p = 0.014), maximal enhancement during arterial phase (OR, 6.15; 95% CI: 1.13–33.51; p = 0.036), no vessel involvement (OR, 7.19; 95% CI: 1.51–34.14) and no Wirsung duct dilatation (OR, 10.63; 95% CI: 2.27–49.91) were independently associated with PPM. A nomogram based on CT features identified at multivariable analysis yielded an AUC of 0.92 (95% CI: 0.85–0.98) for the diagnosis of PPM vs. PDAC.

Abstract

Purpose: To report the computed tomography (CT) features of pancreatic parenchymal metastasis (PPM) and identify CT features that may help discriminate between PPM and pancreatic ductal adenocarcinoma (PDAC). Materials and methods: Thirty-four patients (24 men, 12 women; mean age, 63.3 ± 10.2 [SD] years) with CT and histopathologically proven PPM were analyzed by two independent readers and compared to 34 patients with PDAC. Diagnosis performances of each variable for the diagnosis of PPM against PDAC were calculated. Univariable and multivariable analyses were performed. A nomogram was developed to diagnose PPM against PDAC. Results: PPM mostly presented as single (34/34; 100%), enhancing (34/34; 100%), solid (27/34; 79%) pancreatic lesion without visible associated lymph nodes (24/34; 71%) and no Wirsung duct enlargement (29/34; 85%). At multivariable analysis, well-defined margins (OR, 6.64; 95% CI: 1.47–29.93; p = 0.014), maximal enhancement during arterial phase (OR, 6.15; 95% CI: 1.13–33.51; p = 0.036), no vessel involvement (OR, 7.19; 95% CI: 1.512–34.14) and no Wirsung duct dilatation (OR, 10.63; 95% CI: 2.27–49.91) were independently associated with PPM. The nomogram yielded an AUC of 0.92 (95% CI: 0.85–0.98) for the diagnosis of PPM vs. PDAC. Conclusion: CT findings may help discriminate between PPM and PDAC.

Pictorial Review of Rare Pancreatic Tumors and Tumor-Like Lesions

췌장에는 다양한 종류의 종양 및 종양 유사 병변들이 생길 수 있다. 이 가운데, 췌장선암은 췌장의 가장 흔한 종양으로서 일반적으로 췌장암이라고 하면 이 종양을 가리킨다. 최근에는 영상 검사의 기술적 진보와 이용이 증가하면서 췌장의 희귀 종양 및 종양 유사 병변들의 발견 빈도가 증가하고 있다. 췌장의 드문 종양 및 종양과 유사한 병변들은 치료 방침과 예후가 췌장선암과 다르기 때문에 이들 질환의 감별은 임상적으로 중요한 의의가 있다. 영상 검사는 포상세포암이나 신경초종 등의 희귀 종양 및 자가면역 췌장염 또는 염증성 거짓종양과 같은 종양 유사 병변들과 췌장선암의 감별 진단에 중요한 역할을 하지만 영상 소견만으로 이들 질환을 정확히 구분하는 것은 한계가 있다. 이 논문에서는 췌장에서 생길 수 있는 희귀 종양 및 종양 유사 병변들의 다양한 영상 소견들과 췌장선암과의 감별에 있어 도움이 되는 특징들을 제시하고자 한다.