Surgical resection of cerebellar hemangioblastoma with enhanced wall thickness: A report of two cases

Abstract

Abstract. Hemangioblastomas are tumors of the central nervous system, and the cerebellum is the most common site of occurrence. Cerebellar hemangioblastoma with enhanced wall thickness is rare and often misdiagnosed preoperatively. At present, no unified radiological classification system based on magnetic resonance imaging (MRI) findings exists for cerebellar hemangioblastoma, and this tumor type can be solid or cystic mass, according to the MRI findings. The most common presentation of cerebellar hemangioblastoma observed radiologically is a large sac with small nodules, where the wall of the large cyst is not enhanced. A tumor with enhanced large cysts and tumor nodules is extremely rare. The most effective treatment is complete resection of the cyst and the solid growth. The present case reports the successful treatment of two cases of cerebellar hemangioblastoma with enhanced wall thickness, including the MRI findings for the differential diagnoses and the surgical experiences. IntroductionHemangioblastomas are tumors of the central nervous system that most frequently arise from the vascular system; they are classed as is WHO grade I tumors (1). In adults, 7-10% of tumors arise in the posterior fossa (2) and the cerebellum is the most common site of occurrence (3,4). As a number of features may be observed on magnetic resonance imaging (MRI), (1,(3)(4)(5)(6) according to previous reports, cerebellar hemangioblastoma can be predominantly divided into two categories on the basis of MRI findings. The most common radiological presentation of cerebellar hemangioblastoma is a large sac or cyst and small tumor nodules. We hypothesize that this type may be further divided into two subtypes: One which exhibits no enhancement at the wall of the large cyst, but with evenly enhanced tumor nodules; and another with an enhanced large cyst and tumor nodules. The less common type of cerebellar hemangioblastoma is a solid mass, and also comprises two subtypes: One type contains multiple solid tumors and exhibits homogeneous enhancement on MRI; the other subtype is a solid tumor with single or multiple cysts, where the solid portion is enhanced and the cystic region is non-enhanced (7). In addition to the two main tumor types, the rarest variant of this tumor exhibits an enhanced cyst wall, based on the cystic nodules, and is accompanied by enhanced uneven walls (6). The first type (a large sac or cyst with small tumor nodules) has surrounding edema. The other two types (one type is a solid mass, one type exhibits enhanced cyst wall) exhibit an obvious mass and do not have surrounding edema. However, in spite of these characteristic features on imaging, in the preoperative and differential diagnoses, solid cerebellar hemangioblastoma and nodular cerebellar hemangioblastoma with enhanced wall are often misdiagnosed as high-grade gliomas (6).For cerebellar hemangioblastoma with an enhanced cystic wall, surgical resection is the most effective treatment. The tumor is unlikely to recur following complete resection, therefore che...

Hemangioblastoma masquerading as a ring enhancing lesion in the cerebellum

“…[ 4 , 8 ] These types are categorized into 2 subtypes: cerebellar HGMBs composed of large cysts with no enhanced cystic walls but with uniformly enhanced tumor nodules, and cerebellar HGBMs composed of large cysts with enhanced cystic walls and tumor nodules. [ 4 , 8 ] The less common types of cerebellar HGBM are often solid tumors. [ 4 , 8 ] These types are further categorized into two subtypes: cerebellar HGMBs composed of multiple solid tumors with homogeneous enhancement, and cerebellar HGBMs composed of solid tumors with a single or multiple cysts.…”

“…[ 4 , 8 ] The less common types of cerebellar HGBM are often solid tumors. [ 4 , 8 ] These types are further categorized into two subtypes: cerebellar HGMBs composed of multiple solid tumors with homogeneous enhancement, and cerebellar HGBMs composed of solid tumors with a single or multiple cysts. [ 4 , 14 ] The solid portion is often enhanced, whereas the cystic portion is non-enhanced.…”

“…[ 4 , 8 ] The 2 rarer types are composed of a solid tumor or a lesion with either a ring-enhanced cystic wall or no enhanced cystic component. [ 4 , 8 ] Surgical resection is the most effective and efficient treatment modality for cerebellar HGBMs with enhanced cystic walls. [ 4 , 8 ] HGBMs with ring-enhanced walls are rare, and to date, only a few cases have been described.…”

“…[ 4 , 8 ] Surgical resection is the most effective and efficient treatment modality for cerebellar HGBMs with enhanced cystic walls. [ 4 , 8 ] HGBMs with ring-enhanced walls are rare, and to date, only a few cases have been described. [ 1 , 4 , 8 , 9 ] Thus, we present a rare case of HGBM masquerading as a ring-enhancing lesion in the cerebellum.…”

“…[ 4 , 8 ] HGBMs with ring-enhanced walls are rare, and to date, only a few cases have been described. [ 1 , 4 , 8 , 9 ] Thus, we present a rare case of HGBM masquerading as a ring-enhancing lesion in the cerebellum.…”