Intracranial collision tumor mimicking an octreotide-SPECT positive and FDG-PET negative meningioma.

OBJECTIVE/IMPORTANCE: Cancer metastasis to a pre-existing intracranial tumor is rare, but several cases have been reported. We report an unusual case of a "collision tumor" consisting of a renal cell carcinoma metastasis to an intracranial meningioma. CLINICAL PRESENTATION: A 67-year old male with renal cell carcinoma had an asymptomatic right posterior frontal dural-based lesion identified on a screening CT scan. MRI characteristics of the tumor were consistent with meningioma. On octreotide-SPECT and F-18 fluorodeoxyglucose (FDG)-PET scans, the lesion showed octreotide uptake but did not accumulate FDG, both of which are consistent with a diagnosis of benign meningioma. One week later, he presented with a 1-day history of progressive left-sided weakness. The intracranial tumor was resected, and subacute subdural blood was found overlying a soft, reddish tumor. Microscopic examination was consistent with renal cell carcinoma with a minor portion consisting of meningioma. The meningothelial component was strongly immunoreactive to vimentin and weakly reactive to epithelial membrane antigens. Neither area reacted with glucose transporter-1 (GLUT-1), correlating with low FDG-PET uptake. CONCLUSION: Collision tumor involving metastatic renal cell carcinoma to an intracranial meningioma is a rare occurrence. Diagnosis by non-invasive means, with use of a combination of octreotide-SPECT and FDG-PET may not accurately reflect the malignant component of such a collision tumor. In this case, the collision tumor also demonstrated a propensity to undergo spontaneous hemorrhage. A high degree of suspicion of intracranial metastasis should be maintained for patients who have known systemic cancer and are found incidentally to have a dural-based mass lesion.     

Isolated pineal region metastasis of small cell lung cancer.

The pineal region is an unusual site for brain metastasis and most metastatic pineal lesions are asymptomatic. Rarely the symptoms of metastatic involvement of the pineal gland precede those of the primary tumor or other metastatic sites. An 83 year-old man presented with gait disturbance and limitation of upward gaze. Brain MRI showed homogeneous enhancement of a solitary mass in the pineal region with obstructive hydrocephalus. A stereotactic biopsy was performed, and small cell carcinoma was diagnosed. A systemic investigation for the primary lesion subsequently revealed small cell carcinoma of the lung. The patient was referred for radiotherapy and chemotherapy. Although rare, metastatic tumor should be considered in the differential diagnosis of pineal region tumors, particularly in elderly patients.     

Primary spinal melanoma with bilateral papilledema

A case of primary leptomeningeal malignant melanoma localized in the cervical region in a 41-year-old woman is presented. The only clinical finding was intracranial hypertension with papilledema. A diagnosis of primary CNS melanoma was made after dermatological and ophthalmological consultations, ruled out a metastatic lesion. Primary leptomeningeal melanoma is an extremely rare spinal tumor. Its clinical presentation with signs of increased intracranial pressure but without cord symptoms is unusual. Clinical features of this case including the radiological and histologic findings are described. Diagnosis as well as management is discussed.     

Radioimmunoassay of alpha-fetoprotein in children with primary intracranial tumors.

Serum alpha-fetoprotein (AFP) was measured in 10 cases of primary brain tumors in children (4 cases of medulloblastoma, 4 cases of germ cell tumor and 2 cases of astrocytoma). As a result, elevation in AFP was observed only in a case of embryonal carcinoma that showed partial mixture of germinoma. The absence of AFP elevation in 3 other cases of pure germinoma (atypical teratoma; pinealoma) agrees with reports which describe that, in the germ cell tumor of the gonads, a rise in AFP is not observed in pure seminoma but is found in embryonal carcinoma and endodermal sinus tumor (yolk sac tumor). The fluctuations in AFP in serum and cerebrospinal fluid are considered to be of significance in the diagnosis and treatment of primary intracranial malignant germ cell tumors.     

Primary intracranial ependymoblastoma presenting as spinal cord compression due to metastasis

A primary intracranial ependymoblastoma presented only with symptoms of spinal cord compression due to metastatic spread of the tumor via the leptomeninges. Such a presentation is very rare among primary neoplasms of the central nervous system (CNS) and unique among the 12 previously reported ependymoblastomas. The previous cases all arose as primary brain tumors and several were remarkable for extensive leptomeningeal spread of the tumor. These observations and the presentation of our patient suggest that a histological diagnosis of ependymoblastoma of the spinal cord, with or without symptoms of intracranial tumor, should suggest that an intracranial primary lesion might be present.     

Intracranial germ cell tumors: pathobiological and immunohistochemical aspects of 70 cases

Seventy cases of histologically verified intracranial germ cell tumor were reviewed: 43 germinomas, 16 immature teratomas, seven mature teratomas, two embryonal carcinomas, one choriocarcinoma, and one yolk sac tumor. The male-to-female ratio was 2.6:1. The average age was 19 years in patients with germinoma, 11 years in patients with immature teratoma, and 17 years in patients with mature teratoma. Duration of symptoms averaged 19 months for germinoma, three months for immature teratoma, and 11 months for mature teratoma. Sixty-six lesions were located in the midline. Fifty-eight percent of the germinomas arose anterior to the pineal gland, whereas 29% of the immature and 14% of the mature teratomas were located anteriorly. The histologic appearance of the germinomas was indistinguishable from that of the usual testicular seminoma. The immature teratomas contained tissue from all three germ layers and exhibited morphologic features of fetal tissue. Of 14 immature teratomas, seven contained, in addition, foci of other malignant germ cell elements; thus, there were two teratocarcinomas, two lesions with germinoma and immature teratoma, two lesions with extensive rhabdomyoblastic differentiation in an immature teratoma, and one lesion with both germinoma and embryonal carcinoma in addition to immature teratoma. The seven mature teratomas consisted of fully differentiated epithelial and mesenchymal tissues. In 23 cases, immunoperoxidase stains for human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP), and carcino-embryonic antigen (CEA) revealed patterns which, with minor exceptions, were essentially identical to those found in genital germ cell lesions. Survival was longest for patients with germinomas. In classifying germ cell tumors of the central nervous system, the World Health Organization's (WHO) classification of testicular germ cell tumors is preferable to its present classification of intracranial germ cell tumors.     

Primary Intracranial Squamous Cell Carcinoma in the Brain Stem with a Cerebellopontine Angle Epidermoid Cyst

Primary intracranial squamous cell carcinoma is extremely rare, with most cases arising from a preexisting benign epidermoid cyst. We report a rare case of primary intracranial squamous cell carcinoma in the brain stem with a cerebellopontine angle (CPA) epidermoid cyst. A 72-year-old female suffered from progressive left hemiparesis, difficulty in swallowing, and right hemifacial numbness. Diffusion-weighted magnetic resonance imaging revealed a high signal intensity (SI) lesion in the CPA region and an intra-axially ring-enhanced cystic mass in the right brain stem with low SI. Whole-body positron emission tomography showed no evidence of metastatic disease. The histological findings revealed a typical epidermoid cyst in the CPA region and a squamous cell carcinoma in the brain stem. We speculate that the squamous cell carcinoma may have been developed due to a chronic inflammatory response by the adjacent epidermoid cyst. The patient underwent a surgical resection and radiotherapy. After 12 months, she had no evidence of recurrence.     

Esophageal carcinoma metastasis to cerebellum: a case report

Esophageal carcinoma metastatic to the cerebellum and causing cerebellar compression is a rare entity. The authors report on the case of a 54-year-old woman in whom a metastatic cerebellar tumor secondary to esophageal carcinoma was treated. The patient presented with progressively increasing occipital headache. Computerized tomography scanning and magnetic resonance imaging results revealed a mass lesion in the cerebellum. Because of her previous esophageal carcinoma history, metastatic tumor to the cerebellum was assumed, and the patient underwent total resection of the tumor via median suboccipital approach. Histological examination of the specimen showed a metastatic adenocarcinoma of the esophagus. Postoperatively, the patient received 41 Gy radiation as adjuvant therapy. This case represents an addition to the reported literature of such a rare lesion. The diagnosis, treatment, and pathological findings of this case are presented and the pertinent literature is reviewed.     

A rare bone–leptomeningeal metastasis from an adrenal cortical carcinoma

We report a rare bone–leptomeningeal metastasis from an adrenal cortical carcinoma (ACC). ACC is a rare malignancy and represents one of the most unusual sources of intracranial metastases (0–0.2%); the localization to the skull bone and meninges is uncommon. A 45-year-old man underwent surgery for a non-functioning ACC; 4 months later he developed a soft left frontal mass. The CT scans and MRI showed a large tumor with bone and leptomeningeal involvement. Despite chemotherapy, the lesion increased in volume, which led to local pain and right hemiparesis. Thus, the patient underwent excision of the mass; histopathological diagnosis confirmed that it was an ACC metastasis. The patient underwent standard radiation therapy after surgery. At post-operative follow-up, the patient was in a good neurological condition with no radiological evidence of a cranial recurrence; however, there was a voluminous abdominal regrowth of the primary tumor. To our knowledge, this is the second case of bone and leptomeningeal metastasis arising from an ACC. This patient report confirms the effectiveness of aggressive surgery for management of large intracranial metastases, particularly those that arise from primary tumors that are resistant to radiotherapy and chemotherapy. In our opinion, surgery represents the most appropriate treatment for voluminous intracranial metastasis – even when there are no neurological signs.     

Metastatic spinal cord compression of testicular yolk sac tumor

INTRODUCTION: Pediatric testicular tumors are rare. Spinal metastasis of testicular yolk sac tumor (YST) is extremely rare, with only one reported case. CASE REPORT: We report a rare case of metastatic spinal cord compression of testicular YST in a 14-month-old boy who presented with progressive paraparesis and neurological bladder dysfunction. Two months prior to admission, he underwent a left radical orchiectomy for YST of the testis. Magnetic resonance imaging revealed severe spinal cord compression by the ventral epidural mass from T-9 to T-11 and at S-3. Emergency surgical resection was performed for tissue diagnosis and spinal decompression. Histopathological features of the epidural mass indicated metastasis of the testicular YST. CONCLUSION: Although spinal involvement with metastatic YST is rare, it must be considered in children with testicular YST exhibiting evidence of pain or weakness, and surgical decompression followed by adjuvant chemotherapy should not be delayed.     

颅内神经内分泌癌的诊治分析（附15例报道）

目的 探讨颅内神经内分泌癌的临床特征、治疗方法及预后。方法 回顾性分析2013年9月至2018年9月手术治疗的15例颅内神经内分泌癌的临床资料。结果 15例中,单发病灶3例。多发病灶12例。3例单发病灶术中显微镜下全切除,其余12例仅切除引起明显颅内压增高、短期威胁病人生命的病灶;术后病理显示小细胞神经内分泌癌9例,大细胞神经内分泌癌6例。术后仅行放疗8例,同时行放化疗4例,拒绝放化疗1例。术后随访1~12个月,死亡14例,平均生存时间为8个月;1例随访12个月生活基本自理。结论 颅内神经内分泌癌是一类罕见的恶性脑肿瘤,预后差,临床症状和影像学表现缺乏特异性,诊断依靠术后病理学检查,治疗仍然以手术切除为主,辅以放、化疗的综合治疗。     

Surgical treatment options and management strategies of metastatic renal cell carcinoma to the lumbar spinal nerve roots

Spinal nerve root metastasis of renal cell carcinoma is a rare occurrence. In addition to treatment of the primary lesion, surgical resection of the nerve root metastasis, occasionally with sacrifice of the involved nerve, is the accepted standard of treatment. Resection often resolves presenting motor and pain symptoms due to relief of neural compression. We describe two patients with nerve root metastasis of renal cell carcinoma and their management. While locally advanced and metastatic renal cell carcinoma has been shown to be chemo- and radio-resistant, immunotherapy is a promising treatment. Given the high prevalence of systemic disease in patients with intradural metastases, systemic (and possibly intracranial) imaging can be used to identify other potential areas of disease.     

Brain tumor presenting as an acute pure motor hemiparesis

Acute pure motor hemiparesis is a clinical syndrome of isolated hemiparesis usually related to lacunar infarction, although other etiologies have been described. We recently encountered three patients with the abrupt onset of pure motor hemiparesis as the initial manifestation of primary or metastatic brain tumor. In each patient, early computed tomography demonstrated a nonhemorrhagic, right frontal, enhancing mass lesion. While the mechanism whereby brain tumor may present abruptly and simulate a stroke remains uncertain, these cases illustrate that pure motor hemiparesis can be the initial symptom of intracranial tumor. Early computed tomography or magnetic resonance imaging is suggested for all patients who present acutely with pure motor hemiparesis.     

颅内碰撞瘤

目的介绍颅内碰撞瘤的组织病理学特点和临床表现，以提高对该病的认识。方法对2006年7月13日收治的1例碰撞瘤患者的临床表现、影像学特点、神经病理学结果等资料进行回顾性分析。结果主要临床表现为间歇性头痛、发作性意识丧失、抽搐；头部MRI检查显示左侧额叶占位；组织病理学观察可见肿瘤组织中的主要成分为胶质母细胞瘤，次要成分为细胞角蛋白和甲状腺转录因子-1表达阳性的癌组织。结论对于常见肿瘤组织中出现的异常成分应考虑由其他系统转移而来，须详细追问病史并对患者做进一步的体格检查，以避免误诊。     

颅内碰撞瘤

目的介绍颅内碰撞瘤的组织病理学特点和临床表现，以提高对该病的认识。方法对2006年7月13日收治的1例碰撞瘤患者的临床表现、影像学特点、神经病理学结果等资料进行回顾性分析。结果主要临床表现为间歇性头痛、发作性意识丧失、抽搐；头部MRI检查显示左侧额叶占位；组织病理学观察可见肿瘤组织中的主要成分为胶质母细胞瘤，次要成分为细胞角蛋白和甲状腺转录因子-1表达阳性的癌组织。结论对于常见肿瘤组织中出现的异常成分应考虑由其他系统转移而来，须详细追问病史并对患者做进一步的体格检查，以避免误诊。     

Metastatic hepatoma presenting as intracranial hemorrhage: report of two cases

Metastasis of hepatoma to the central nervous system is rare, although hepatoma is a relatively common malignant tumor in Japan. Much rarer is metastatic hepatoma presenting as intracranial hemorrhage and there have been only 4 cases reported in the past. Here, we report two such rare cases with a literature review. Case 1 was a 26 years-old female with a history of 60% hepatic resection in the diagnosis of hepatocellular carcinoma. Later, she developed bilateral lung metastasis. She was admitted with complaints of headache, nausea and vomiting. Neurological findings were clear consciousness, right homonymous hemianopsia and bilateral papilledema. CT showed high-density mass in the left occipital lobe. Evacuation of hematoma and removal of tumor were performed. Pathological diagnosis was hepatocellular carcinoma of clear cell type. Later, two other hemorrhage occurred from different metastatic lesions in the left occipital lobe and the right occipital lobe, and the patient underwent two more surgeries. The patient died of lung metastasis, three months from neurological onset. Case 2 was a 42 years-old male who developed an intracranial tumor adjacent to the right temporal bone without a history of hepatoma. The tumor was removed, which turned out to be hepatocellular carcinoma pathologically. Three months later, on admission, the patient showed sudden neurological deterioration into deep coma. CT showed an irregular high-density mass in the right temporal lobe and evacuation of hematoma coupled with tumor removal was performed. Pathology was of trabecular type. Later, intracranial recurrence and bony metastasis to C5, L3 and the left iliac bone appeared.(ABSTRACT TRUNCATED AT 250 WORDS)     

颅内神经内分泌癌6例报道及文献复习

目的 探讨颅内神经内分泌癌的临床表现、影像学特征、病理学表现、治疗方法及其效果。方法 回顾性分析2000~2018年收治的6例颅内神经内分泌癌的临床资料。结果 肿瘤位于左侧顶枕叶及第四脑室内1例、右侧顶叶1例、右侧额叶3例、小脑半球1例。4例发现肺部占位。术前均误诊为胶质瘤。6例均手术全切肿瘤，术后病检结果示神经内分泌癌。5例术后随访1周至12个月，1例术后未行放、化疗，3个月死亡；4例术后伽玛刀治，1例6个月死亡，3例随访12个月生活基本自理。1例失访。结论 颅内神经内分泌癌是一种极其罕见的疾病，恶性程度高，临床表现和影像学特征不明显，术前诊断较为困难，病理学是诊断的金标准，主要以手术切除为主辅以放、化疗的综合治疗。     

Metastatic Merkel cell carcinoma of the spine

Merkel cell carcinoma is a rare neuroendocrine malignancy, primarily affecting sun-exposed skin. The mean age at presentation is 75 years. To our knowledge there have been only four patients with spinal metastasis reported previously, with one patient alone having a marked neurological deficit requiring surgical decompression. We report a 73-year-old male who presented with rapidly progressive paraplegia 6 months following excision of a primary cutaneous Merkel cell lesion. He had a metastatic deposit at T6 comprising a canal filling epidural component with local aggressive bone destruction. He required emergent surgical decompression and unilateral pedicle screw stabilization. Unfortunately, this patient died 1 month postoperatively, succumbing to overwhelming metastatic disease. This report highlights the locally aggressive nature of metastatic Merkel cell tumor and the very poor prognosis in those patients who develop spinal column metastases.     

Clivus metastasis of squamous cell carcinoma: a rare location.

Lung cancer is the most frequently encountered cancer in humans and commonly metastasizes to brain and bone. Metastasis to the clivus is very rare and there have been no previous reports. A 51-year-old woman was admitted to our hospital complaining of headache, and left shoulder, arm and back pain. The chest X-ray showed a left paracardiac mass measuring 4x4 cm in diameter and the thorax computed tomographic examination revealed a 4x4 cm mass in the left lower lobe, left hilar and mediastinal lymphadenopathy, and multiple lytic lesions in the thoracic vertebral bodies. Head magnetic resonance imaging showed a mass in the clivus with bony destruction. Bronchoscopic examination revealed an exophytic endobronchial lesion in the left lower bronchus lumen and a biopsy was taken from this lesion. The histopathological diagnosis was "poorly differentiated squamous cell carcinoma". A punch biopsy was taken from the clivus via the transnasal-transphenoidal route. Histopathological findings of this biopsy were similar to the primary site tumor. We report a rare case of clivus metastasis from squamous cell lung cancer.