脂肪细胞化生Adipocyte Metaplasia · 脾脏 · 免疫系统 · NTP ntp-0042
诊断要点：无论何时出现，脾脏脂肪细胞化生均应作出诊断并赋予严重程度分级。如果该病变与肿瘤同时存在或继发于肿瘤，则不应记录，但应在病理学叙述中加以描述。
病变描述
在慢性毒性/致癌性研究中，脾脏中偶可见脂肪细胞（adipocyte），但可能与受试物无关。据报道，在暴露于某些芳香胺（如苯胺、盐酸苯胺、对氯苯胺）的大鼠脾脏红髓中以及患有脾脏间叶性肿瘤的大鼠中可见此病变。该病变的特征是红髓内出现分化良好的脂肪细胞（Figure 1、Figure 2，箭头所示），周围环绕纤维性间质（Figure 2，箭头头所示），尽管纤维化不一定总是显著。通常累及红髓，病变可为局灶性（focal）、nodular和/或弥漫性（diffuse）。这些细胞最可能来源于脾脏间质细胞的化生。既往使用的术语包括脾脏的“脂质沉积症（lipidosis）”、“脂肪浸润（fatty infiltration）”、“脂肪变态（fatty metamorphosis）”和“脂质化生（lipid metaplasia）”。
诊断与分级建议（NTP 共识）
无论何时出现，脾脏脂肪细胞化生均应作出诊断并赋予严重程度分级。如果该病变与肿瘤同时存在或继发于肿瘤，则不应记录，但应在病理学叙述中加以描述。
图谱
英文原文
展开 NTP 官方英文描述与建议
Comment：
Adipocytes are occasionally seen in the spleen in chronic toxicity/carcinogenicity studies but may be unrelated to treatment. It has been reported in the red pulp of rats exposed to some aromatic amines (e.g., aniline, aniline hydrochloride, para-chloroaniline) and in rats with splenic mesenchymal neoplasms. This lesion is characterized by well-differentiated adipocytes in the red pulp ( Figure 1 and Figure 2 , arrows), surrounded by a fibrous stroma ( Figure 2 , arrowhead), although fibrosis may not always be prominent. The red pulp is typically involved, and the lesion may be focal, nodular, and/or diffuse. These cells most likely arise by metaplasia of splenic stromal cells. Previous terms include "lipidosis," "fatty infiltration," "fatty metamorphosis," and "lipid metaplasia" of the spleen.
Recommendation：
Whenever present, adipocyte metaplasia of the spleen should be diagnosed and assigned a severity grade. If this lesion is present concurrently or secondarily to neoplasia, it should not be recorded but should be described in the pathology narrative.
来源与引用
原始条目：https://ntp.niehs.nih.gov/atlas/nnl/immune-system/spleen/AdipocyteMetaplasia
图谱总目录：NTP Nonneoplastic Lesion Atlas。 内容属美国联邦政府作品（公有领域），可引用；引用时请标注来源。
建议引用格式：NTP Nonneoplastic Lesion Atlas. Adipocyte Metaplasia (spleen). LabSmart 中文版：
https://www.labsmart.cn/ntp/spleen-adipocyte-metaplasia.html
中文图谱总页（可展开对照全部 595 条）：https://www.labsmart.cn/ntp-atlas.html#spleen-adipocyte-metaplasia