Hosokawa Takahiro, Uchiyama Mayuki
Department of Radiology, Saitama Children's Medical Center, Saitama, Japan.
Department of Radiology, The Jikei University School of Medicine, Minato-Ku, Tokyo, Japan.
Indian J Nucl Med. 2023 Jan-Mar;38(1):41-43. doi: 10.4103/ijnm.ijnm_147_22. Epub 2023 Feb 24.
A craniofacial mass may cause the first clinical symptoms of malignancy. In pediatric patients, neuroblastoma, Langerhans cell histiocytosis (LCH), and acute lymphoblastic leukemia (ALL) are the most common diseases initially manifesting with bone lesions, and bone scintigraphy is a useful modality to evaluate them. The purpose of this pictorial essay was to show the scintigraphy findings of the craniofacial bones in three patients, with neuroblastoma, ALL, and LCH, and to provide a useful scintigraphic sign to differentiate these diseases. In the bone scintigraphy of neuroblastoma with craniofacial bone metastases, strong tracer uptake was evident, resembling a carnival mask. In contrast, in the two cases with LCH and ALL involving the craniofacial bones, the tracer uptake was lower than in neuroblastoma and with different distributions. Bone metastases of neuroblastoma usually occur in the periorbital craniofacial bones, and these metastases may be locally aggressive, destroying the bones; which show stronger uptake than other cranial bones. LCH is associated with varying degrees of disease activity, and its bone imaging findings differ based on its activity. Therefore, these lesions present low uptake in bone scintigraphy, showing as "cold spots". Therefore, LCH scintigraphy of the craniofacial bones does not resemble a carnival mask. The bone marrow infiltration by leukemic cells usually shows as diffuse bone marrow. Therefore, in bone scintigraphy of leukemia, the tracer uptake in the periorbital craniofacial bones is similar to other cranial bones, not presenting as a carnival mask. In conclusion, bone scintigraphy to evaluate malignant craniofacial lesions could provide useful differential diagnostic information.
颅面部肿块可能引发恶性肿瘤的首发临床症状。在儿科患者中，神经母细胞瘤、朗格汉斯细胞组织细胞增多症（LCH）和急性淋巴细胞白血病（ALL）是最初表现为骨病变的最常见疾病，而骨闪烁显像术是评估这些疾病的一种有用方法。这篇图文并茂的文章旨在展示3例分别患有神经母细胞瘤、ALL和LCH的患者颅面部骨骼的闪烁显像结果，并提供一种有助于鉴别这些疾病的有用闪烁显像征象。在伴有颅面部骨转移的神经母细胞瘤的骨闪烁显像中，可见明显的放射性示踪剂浓聚，类似狂欢节面具。相比之下，在2例累及颅面部骨骼的LCH和ALL病例中，示踪剂摄取低于神经母细胞瘤，且分布不同。神经母细胞瘤的骨转移通常发生在眶周颅面部骨骼，这些转移可能具有局部侵袭性，破坏骨骼；其摄取比其他颅骨更强。LCH与不同程度的疾病活动相关，其骨成像结果因活动程度而异。因此，这些病变在骨闪烁显像中表现为摄取低，呈“冷区”。因此，颅面部骨骼的LCH闪烁显像不像狂欢节面具。白血病细胞的骨髓浸润通常表现为弥漫性骨髓。因此，在白血病的骨闪烁显像中，眶周颅面部骨骼的示踪剂摄取与其他颅骨相似，不呈现为狂欢节面具。总之，用于评估恶性颅面部病变的骨闪烁显像可提供有用的鉴别诊断信息。
