Clinical characteristics and treatment outcomes of pigmented tumors in central nervous system: Focusing on melanocytic tumors

Pigmented tumors are rare neoplasm of central nervous system. Melanocytic tumor, including primary and metastatic lesions, is the most common type. Owing to the rarity, the differential diagnosis of pigmented tumors and clinical management of melanocytic tumor remain challenge. Therefore, focusing on melanocytic tumors, the clinical, radiological, histopathological features and treatment outcomes were presented and analyzed in this study. We identified 22 melanocytic tumors, 2 melanotic medulloblastomas, 2 melanotic ependymomas and 1 melanotic schwannoma. Compared with metastatic melanocytic tumors (MMTs), primary melanocytic tumors (PMTs) were characterized by younger age (36.11 ± 17.96 vs. 51.69 ± 12.58 years, p = 0.0262), lower possibility to be multiple lesions (11.1%vs. 61.5%, p = 0.0306), higher proportion of hypointensity on T2-weighted images (66.7% vs. 15.4%, p = 0.0260) and higher frequency in black appearance (77.8% vs. 23.1%, p = 0.0247). During the follow-up, 4 PMTs and 11 MMTs (71.4%) experienced tumor progression. PMTs had better prognosis than MMTs that progression-free survival (PFS) rate of PMT was 50.0% but decreased to 23.1% for MMTs at 12 months (p = 0.0123). Cox proportional hazards regression revealed that multiplicity of tumor was an independent predictor for PFS. None of patient with multiple tumors was in PFS after 12 months’ follow-up whereas PFS rate was 40.5% for single tumor (p = 0.0002). In conclusion, radiological appearances, especially hypointensity on T2-weighted images, might be an indication for PMT. MMTs are more likely to be multiple intraparenchymal masses in elder patients located in supratentorial region. Current treatments included operation, radiotherapy and chemotherapy are not competent to control tumor progression and other therapeutic modalities are urgently needed.     

椎管内原发性黑色素细胞肿瘤(附5例报告)

目的总结椎管内原发性黑色素细胞肿瘤的临床特点。方法分析5例椎管内黑色素细胞起源肿瘤病人的临床资料，结合文献，对其流行病学、病理类型、影像特征、诊治和预后等进行讨论。结果本组男3例，女2例；年龄31-47，平均38-2岁。椎管内肿瘤单发4例，多发1例；髓外硬膜下4例，髓内1例。短T1、短T2信号为其典型MRI特征。病理诊断为恶性黑色素瘤3例，黑色素细胞瘤2例。不同病理类型的治疗方法和预后迥然不同。结论早期诊断、显微手术全切除是获得良好预后的关键；应根据不同病理类型采取适宜的放、化疗措施。     

Primary melanocytic lesions of the CNS: report of five cases

Primary melanocytic tumours of the central nervous system (CNS) form a rare entity which is histologically and clinically distinct from metastatic cutaneous or retinal malignant melanoma. They can be classified into diffuse melanocytosis (diffuse melanosis), malignant melanoma and benign melanocytoma with a small number of intermediate variants. In this paper, 5 cases treated neurosurgically in our department for spinal or cerebral primary CNS malignant melanoma are reported. Primary tumors and further metastases were ruled out. Radiological, histological and clinical features are discussed. Compared to metastatic disease, primary CNS malignant melanoma shows a more benign clinical course with long-term tumour control and a good quality of life. A review of the literature which mainly consists of individual case reports, confirms this assessment. Although therapeutic experience for primary melanocytic lesions of the CNS is based on a small number of published cases, prognosis seems highly dependent on complete tumour resection. Adjuvant radiation seems to be of additional therapeutic benefit. Except for meningeosis melanomatosa chemotherapy must be regarded as experimental. Unfortunately, a standardised therapy concept is still lacking.     

Primary Intracranial Leptomeningeal Melanomatosis

Primary intracranial malignant melanoma is a very rare and highly aggressive tumor with poor prognosis. A 66-year-old female patient presented a headache that had been slowly progressing for several months. A large benign pigmented skin lesion was found on her back. A brain MRI showed multiple linear signal changes with branching pattern and strong enhancement in the temporal lobe. The cytological and immunohiostochemical cerebrospinal fluid examination confirmed malignant melanoma. A biopsy confirmed that the pigmented skin lesion on the back and the conjunctiva were benign nevi. We report a case of primary intracranial malignant melanoma and review relevant literatures.     

Primary melanocytic tumors of the central nervous system: a neuroradiological and clinicopathological study of five cases and brief review of literature

Primary melanocytic tumors of the central nervous system (CNS) are uncommon lesions. These lesions arise from the melanocytes located within leptomeninges and include diffuse melanocytosis and meningeal melanomatosis (seen in neurocutaneous melanosis), melanocytoma, and malignant melanoma. To study, the clinical course, neuroradiological features, morphology and immunohistochemistry of primary melanocytic tumor of CNS. Demographic, clinical and surgico-pathologic findings of five patients with melanocytic tumors seen between 1996 and 2003 were studied. In this study, five cases of primary melanocytic tumors have been reported: four cases of malignant melanoma and one case of melanocytoma. Three of the 5 cases were intracranial and 2 were spinal. The mean age in the present study was 26 years. Presenting features varied according to the location. Primary melanocytic tumor of CNS are rare. Whenever possible, complete surgical excision is the best treatment.     

Transformation of intracranial anaplastic astrocytoma associated with neurofibromatosis type I into gliosarcoma: Case report

Gliosarcoma is an uncommon malignant brain tumor composed of distinct sarcomatous and malignant glial cell elements. These tumors are defined as a variant of glioblastoma, and it can be developed by progression of the malignant glial cell tumors or primary tumors. We report a rare case with gliosarcomatous recurrence of anaplastic astrocytoma with neurofibromatosis type 1 (NF-1) followed by chemoradiation therapy. A 26-year-old male patient was presented with headache. Five years before admission, he had been diagnosed with NF-1. Magnetic resonance imaging (MRI) showed a well-demarcated, enhanced lesion in the right frontal lobe and multiple enhanced lesions in the scalp, lower cervical, thoracic, and upper lumbar regions. He underwent an osteoplastic craniotomy with total tumor resection. Histopathology of the tumor showed findings corresponding with anaplastic astrocytoma. He was followed by radiotherapy and chemotherapy postoperatively. A month later, his spinal lesion was also resected and confirmed pathologically as plexiform neurofibroma. The subsequent follow-up period of 27 months was uneventful until he developed a generalized tonic-clonic seizure. MRI showed tumor recurrence in the original site of the tumor. Re-exploration was carried out. Pathological examination displayed a biphasic pattern of the glial and sarcomatous components suggesting gliosarcoma.     

Malignant peripheral nerve sheath tumor with divergent cartilage differentiation from the acoustic nerve: case report]

Malignant peripheral nerve sheath tumors(MPNSTs) of the acoustic nerve are very rare. Only seven cases of MPNST arising from the acoustic nerve have been reported. The authors present a case of MPNST with divergent cartilage and melanotic differentiation of the acoustic nerve. The patient was a 69 year old man admitted to our neurosurgical service in January 1999 complaining of left facial nerve palsy and hearing difficulty of his left ear. The initial CT showed a tumor at the left cerebellopontine angle region. On MRI the tumor was depicted as low intensity on T 1-weighted image and high intensity on T 2-weighted image, the mass was heterogeneously enhanced after administration of Gd-DTPA. The partial removal of the tumor was performed in January 1999. He was discharged February 1999. But he was admitted again because of progressive cerebellar ataxia. MRI showed the rapid regrowth of the residual tumor. In March 1999, complete removal of the tumor was performed. Histopathological analysis revealed a malignant spindle cell neoplasm with divergent cartilage and melanotic differentiation. We review the relevant literature concerning MPNST of the acoustic nerve and discuss the clinical features of malignant eighth cranial nerve tumor.     

Fulminant leptomeningeal carcinomatosis from a malignant melanoma arising in a cerebellopontine epidermoid cyst: A rare case with diagnostic pointers

A malignant component in an epidermoid cyst is rare. We report an exceptionally rare case of a malignant melanoma arising in an epidermoid cyst located in the cerebellopontine (CP) angle. A 26‐year‐old woman presented with headache, vomiting, ataxia and difficulty in swallowing over the previous 3 months. The radiological finding suggested an epidermoid cyst and the lesion was excised. The histopathology confirmed a CP angle epidermoid cyst. Within 1 month of discharge, she developed hydrocephalus for which a ventriculo‐peritoneal shunt was performed. Postoperatively she developed weakness in lower limbs. A contrast‐enhanced MRI was done which showed dilated CSF cisternal spaces with a small enhancing lesion in the pineal region and enhancement of meninges extending to the spinal cord. Re‐exploration showed gelatinous material with gross adhesions in the CP angle cistern. A dural biopsy was done which showed sheets of poorly differentiated tumor cells which expressed S100 and Melan A and were immunoreactive with Human Melanoma Black (HMB)‐45 antibody, consistent with the diagnosis of malignant melanoma. Histology of the excised epidermoid cyst was re‐evaluated in deeper sections and showed scattered atypical melanocytes in the basal layer of the epidermis which were highlighted with HMB‐45 antibody. The patient expired within 3 days of the second procedure due to respiratory failure. A very aggressive fulminant course of the disease was evident after surgery for the epidermoid cyst. Treatment options are limited. Criteria for identification of malignancy in an intracranial epidermoid cyst were identified in our case retrospectively and have been highlighted.     

Variante amelanótica en melanoma cerebral primario: a propósito de un caso

Primary brain melanoma is a very rare tumour (only 0.07% of primary CNS neoplasms) which usually shows with abundant melanin content; whereas hypo/melanotic variants have been scarcely described.We introduce the case of a female patient with headache, left brachial paresis and frontal lobar syndrome. The MRI image showed a right frontal mass with homogeneous contrast uptake. As treatment, a complete surgical resection was performed. Pathology was diagnostic for melanoma, with very low melanin content and a high proliferative index. A thorough extension study was performed to rule out an extracranial primary origin. Due to several intercurrent complications, the patient evolved unfavorably, not being able to receive further treatment.The amelanotic variant of primary intracranial malignant melanomas has not been described in detail previously. We will review the literature, focusing on the particularities of management and diagnosis of this clinical entity.     

Primary meningeal intermediate grade melanocytic neoplasm: case report with radiologic-pathologic correlation

A case of primary meningeal intermediate grade melanocytic neoplasm involving the right C2 nerve root is presented. MRI findings may suggest this rare entity, especially when an extra-axial lesion is located in the posterior fossa or cervical spinal canal and demonstrates shortening of both T1 and T2. Eventually, definitive diagnosis relies on histology which demonstrates spindle-shaped melanocytic cells that are Fontana stained and positive for HMB:45 antigen. Cellularity, pleomorphism, mitotic rate, proliferation index and invasiveness are useful criteria to distinguish among the spectrum of primary melanocytic tumors of the central nervous system ranging from melanocytoma to malignant melanoma.     

Primary spinal melanoma: a case report

Intra spinal primary melanoma is a rare entity. We report a new case, atypical in relation to its primary radicular location, and to its early metastatic intradural and extra-medullary location, six months later. MRI is the more valuable examination, showing a spontaneously hyper-intense lesion on T1-weighted MR images, intense enhancement after gadolinium administration, and decreased signal on T2-weighted MR images, thus suggesting a diagnosis of melanocytic or hemorrhagic lesion. Signal abnormalities are not specific and definitive diagnosis is established after histological analysis.     

Malignant meningioma as a second malignancy after therapy for acute lymphatic leukemia without cranial radiation

Rationale Meningiomas in the pediatric age group are very rare tumors, comprising about 1–4.2% of all primary pediatric intracranial tumors.Case report We present a 17-year-old patient who suffered from an intraventricular malignant meningioma. At the age of 2 years, acute lymphatic leukemia (common ALL [cALL]) was diagnosed and successfully treated with chemotherapy. There was no cranial radiation therapy.In December 2001, 13 years after diagnosis of cALL, he complained of headache, vomiting, and walking difficulties. Magnetic resonance imaging showed an enhancing mass with cystic components in the trigone of the right lateral ventricle. The tumor was removed completely. Histological diagnosis revealed a malignant papillary meningioma. After removal of a recurrent meningioma 16 months later, he received local radiotherapy.Conclusion Pathogenetic mechanisms, treatment options, and prognosis of meningiomas and secondary malignancies of this age group are discussed.     

The diagnostic dilemma of primary central nervous system melanoma

Melanomas are malignant neoplasms of melanocytes developing predominantly in the skin, but occasionally arising from eyes, mucous membranes, and the central nervous system (CNS). The CNS can be affected by a spectrum of melanocytic lesions ranging from diffuse neurocutaneous melanosis, to a focal and benign neoplasm (melanocytoma), and to an overtly malignant tumor (melanoma). Primary melanocytic lesions involving the CNS are typically concentrated in the perimedullary and high cervical region. Primary CNS melanoma cannot be reliably distinguished from metastatic melanoma on neuroimaging and histopathological characteristics alone: its diagnosis is established only after exclusion of secondary metastatic disease from a cutaneous, mucosal or retinal primary. We present two patients with primary CNS melanoma and discuss relevant issues, available treatment options, and expected outcomes. Awareness of disease spectrum and clinico-biological differences may be used to guide therapeutic decision-making for a patient with a proven or suspected primary CNS melanoma.     

颅内转移性恶性黑色素瘤：一例报告并文献复习

目的探讨颅内转移性恶性黑色素瘤临床组织病理学及免疫组织化学特征。方法应用组织病理学及免疫组织化学检测方法对1例颅内多发转移性恶性黑色素瘤患者的两次手术标本进行观察,通过复习文献分析其组织病理学和免疫组织化学特征,提出诊断与鉴别诊断要点。结果男性患者,48岁。因颅内多发占位性病变、肿瘤卒中而行右侧额颞叶肿瘤切除术。两次手术标本组织病理学表现不一：首次右侧额叶病灶表现为异型性上皮样肿瘤细胞围绕毛细血管和纤维组织呈乳头状排列;再次手术标本为右侧颞叶,病灶表现为梭形细胞呈片巢状或束状排列,胞质丰富、淡染或透亮,胞核异型性明显、核仁呈明显嗜酸性。左侧腹股沟淋巴结活检提示肿瘤转移,且肿瘤组织局部可见大量黑色素颗粒。免疫组织化学染色肿瘤细胞弥漫表达S一100蛋白、人黑色素细胞瘤抗原45、Melan—A和波形蛋白,部分表达上皮膜抗原,而细胞角蛋白、高分子角蛋白、低分子角蛋白、胶质纤维酸性蛋白、突触素、神经微丝蛋白等表达阴性。结论颅内转移性恶性黑色素瘤的组织学表现复杂多样,临床病史和影像学资料对诊断具有重要参考价值,但明确诊断仍需依靠免疫组织化学检测结果。需注意与转移癌、脑膜肿瘤、淋巴瘤及其他含黑色素的颅内肿瘤相鉴别。     

颅内转移性恶性黑色素瘤:一例报告并文献复习

目的探讨颅内转移性恶性黑色素瘤临床组织病理学及免疫组织化学特征。方法应用组织病理学及免疫组织化学检测方法对1例颅内多发转移性恶性黑色素瘤患者的两次手术标本进行观察,通过复习文献分析其组织病理学和免疫组织化学特征,提出诊断与鉴别诊断要点。结果男性患者,48岁。因颅内多发占位性病变、肿瘤卒中而行右侧额颞叶肿瘤切除术。两次手术标本组织病理学表现不一:首次右侧额叶病灶表现为异型性上皮样肿瘤细胞围绕毛细血管和纤维组织呈乳头状排列;再次手术标本为右侧颞叶,病灶表现为梭形细胞呈片巢状或束状排列,胞质丰富、淡染或透亮,胞核异型性明显、核仁呈明显嗜酸性。左侧腹股沟淋巴结活检提示肿瘤转移,且肿瘤组织局部可见大量黑色素颗粒。免疫组织化学染色肿瘤细胞弥漫表达S-100蛋白、人黑色素细胞瘤抗原45、Melan-A和波形蛋白,部分表达上皮膜抗原,而细胞角蛋白、高分子角蛋白、低分子角蛋白、胶质纤维酸性蛋白、突触素、神经微丝蛋白等表达阴性。结论颅内转移性恶性黑色素瘤的组织学表现复杂多样,临床病史和影像学资料对诊断具有重要参考价值,但明确诊断仍需依靠免疫组织化学检测结果。需注意与转移癌、脑膜肿瘤、淋巴瘤及其他含黑色素的颅内肿瘤相鉴别。     

Intermediate grade meningeal melanocytoma of cervical spine

Background  Meningeal melanocytoma is a rare, benign melanotic tumor of the leptomeninges, which occurs anywhere in the cranial or spinal regions but most commonly in supratentorial and thoracic spine regions. The literature on this entity consists of case reports; therefore, there is no agreement on the most effective therapy of this tumor, although total excision seems to be the best therapeutic option. Case history  We report a 17-year-old girl with intermediate grade meningeal melanocytoma involving the C6 nerve root with spinal cord compression resulted in progressive tetraparesis. Clinical and radiological examinations suggested the possibility of an intradural extramedullary solid mass. The tumor was removed subtotally through cervical laminotomy followed by rapid improvement of most neurological deficits. This tumor was unusual because of its very hyperintense homogenous signal on T1-weighted images, invasion of the arachnoid membrane, and extension into the neural foramina. Black dots on the surface of the cord were thought to represent an organized blood clot until the frozen section suggested a melanocytic tumor. Discussion  We discuss the distinction of meningeal melanocytoma from other melanocytic tumors of the leptomeninges. Conclusion  Melanocytic tumors should be considered in the differential diagnosis when a hyperintense lesion of the leptomeninges is identified on T1-weighted images or a very dark mass similar to charcoal or organized hematoma is found in the surgical field. The best management is complete tumor resection, but radiotherapy is reserved in cases of subtotal resection and multiple lesions. Locally aggressive nature of tumor and possibility of recurrence warrant regular follow-up.     

Primary amelanotic meningeal melanomatosis

Primary melanocytic lesions of the central nervous system are rare. The spread of melanoma cells primarily into the meningeal layers is referred to as meningeal melanomatosis. A few case reports about either intracranial or intraspinal primary meningeal melanoma were published in the past. The amelanotic variation of primary melanoma in the central nervous system is a very rare event and so far no cases of primary amelanotic meningeal melanomatosis have been described in the current literature. We present a case with combined multiple intracranial and intraspinal primary malignant amelanotic melanomas.     

Primary cerebellopontine angle angiosarcoma

Primary intracranial angiosarcomas are rare. Only a few cases have been reported in the literature. All cases reported were located in the supratentorial areas. To our knowledge, no cerebellopontine (CP) angle angiosarcoma has been reported. We report a 16-year-old girl who had mild headache, right-sided tinnitus and amblyacousia of 1-year's duration. She later developed abruptly severe headache and vomiting, accompanied by left hemiparesis, numbness, ataxia and bucking, and computerized tomography scan and magnetic resonance imaging were performed. There was a lesion in the right CP angle with haemorrhage and edema. The preoperative diagnosis was neurogenic tumor with haemorrhage. The patient underwent an emergency suboccipital craniectomy, and the lesion was excised completely. Histopathology and immunohistochemistry revealed an angiosarcoma. Postoperative radiotherapy was given. At the time of hospital discharge, she was in better clinical and neurological condition than her preoperative state. She has been followed up for 6 months and is is still in excellent condition without any sign of recurrence. This case report highlights that clinicians should be aware of the characteristics of angiosarcoma, and also stresses the need to include angiosarcoma in the differential diagnosis of rare lesions located in the CP angle.     

A case of intracranial amelanotic melanoma

Malignant melanoma is usually black in color because of the existence of melanin pigments in it. Differing from such a usual melanoma, amelanotic melanoma, which has no melanin pigments and is not black-colored, is rarely described in literature. In this report, a case of intracranial amelanotic melanoma of unknown origin is presented and discussed. This represents the seventh case report of an intracranial amelanotic melanoma. On May 28, 1984, a 55-year-old man was admitted to our department because of repeated left hemiconvulsion. Neurological and physical examination disclosed left hemiparesis, poor concentration and right inguinal tumors. CT scan revealed a right posterior frontal mass with ring like enhancement. On June 7, the patient underwent craniotomy. The brain tumor, partly emerged from right frontal lobe, was reddish and easy to bleed. Macroscopically there were no abnormal findings over leptomeniges. The right inguial tumors, that were lymph nodes, were also removed simultaneously. Microscopic interpretation at that time was that of a malignant tumor of ectodermal origin. Although no melanin pigments were demonstrated in any specimens except for a part of lymph nodes, dopa reaction was positive in both specimens from the brain tumor and the inguial lymph nodes, strongly suggesting amelanotic melanoma. Postoperative course was uneventful, but CT scan of Aug. 31 again showed multiple intracerebral enhanced lesion and ventricular hemorrhage. Aphasia, right hemiparesis and consciousness disturbance developed gradually, and he died on Sept. 21, 1984. Autopsy demonstrated multiple intracerebral hematomas, containing much tumor cells in lung, thyroid and subcutaneous tissue. Primary lesion remained unknown in spite of an extensive examination in autopsy.(ABSTRACT TRUNCATED AT 250 WORDS)