Malignant Carotid Paraganglioma: A Case Report

Carotid body tumors (CBTs) are rare neoplasms of the neuroectoderm accounting for 0.6% of head and neck tumors, with a 2%-12.5% risk of malignancy. While surgical resection has been associated with a high rate of neurologic and vascular complications, it remains the mainstay of treatment for malignant CBTs. We present the case of a 40-year-old female with a 5-year history of progressively enlarging right-sided neck mass, with MRI and MRA showing a Shamblin grade III CBT encasement of the internal carotid artery (ICA). Blood flow was absent in the petrous segment of ICA, with great collateralization of brain blood supply, enabling en bloc resection of the tumor with a carotid bulb and ligation of the common carotid artery (CCA) without vascular reconstruction. Further, we describe the characteristics and current management for malignant CBTs, including surgical management, pre-surgical embolization, and adjuvant radiation therapy.

Comprehensive Genetic Study of Malignant Cervical Paraganglioma

Malignant middle ear paraganglioma (MEPGL) is an exceedingly rare tumor of the neuroendocrine system. In general, MEPGLs represent as slow growing and hypervascularized benign neoplasms. The genetic basis of MEPGL tumorigenesis has been poorly investigated. We report a case of malignant MEPGL accompanied by the comprehensive genetic analysis of the primary tumor and metastasis. Based on whole-exome sequencing data, the germline pathogenic mutation p.R230H in the SDHB gene, encoding for subunit B of mitochondrial complex II, was found in a patient. Analysis of somatic mutation spectra revealed five novel variants in different genes, including a potentially deleterious variant in UNC13C that was common for the tumor and metastasis. Identified somatic variants clustered into SBS1 and SBS5 mutational signatures. Of note, the primary tumor was characterized by Ki-67 4% and had an elevated mutational load (1.4/Mb); the metastasis' mutational load was about 4.5 times higher (6.4/Mb). In addition, we revealed somatic loss of the wild-type SDHB allele, as well as loss of heterozygosity (LOH) at the 11p locus. Thus, germline mutation in SDHB combined with somatic LOH seem to be drivers that lead to the tumor's initiation and progression. Other somatic changes identified can be additional disease-causing factors. Obtained results expand our understanding of molecular genetic mechanisms associated with the development of this rare tumor.

[131I]I-MIBG-negative metastases of a recurrent sporadic paraganglioma in a female with achondroplasia

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Autopsy of malignant paraganglioma causing compressive myelopathy due to vertebral metastases

Paraganglioma is a neuroendocrine tumor arising from extra-adrenal sites in the peripheral nervous system. Although malignant paraganglioma is known to metastasize to bones, including vertebral bodies, there is little literature on the compressive myelopathy accompanied by sphincter dysfunction; to our knowledge, only 12 cases have been reported. Moreover, neuropathological investigations of the spinal cord in this state have not been well-documented. This autopsy report describes a 55-year-old man with malignant paraganglioma and compression myelopathy caused by vertebral metastasis. The present case showed a gradual numbness and a sudden onset of irreversible paraplegia with sphincter dysfunction, which were not palliated these neurologic dysfunctions despite radiotherapy. Computed tomography (CT) revealed multiple metastases to the bones, lymph nodes, and lungs when he was diagnosed with malignant paraganglioma. At the same time, he had numbness, and magnetic resonance imaging (MRI) showed multiple diffuse metastatic lesions in the vertebral bodies. Following abrupt onset of paralysis, MRI showed fractured third and sixth thoracic vertebral bodies. An autopsy revealed residual vertebral metastases with fractures of the third and sixth thoracic vertebral bodies, resulting in compressive myelopathy at the fourth thoracic segment, which was characterized by complete spinal cord destruction. Destructive spinal cord lesion-induced secondary degeneration was observed in the gracile fasciculus at the rostral side and in the pyramidal tract at the caudal side, which showed Wallerian degeneration. Such pathology was consistent with the presenting neurological symptoms, including paraplegia and somatic sensory loss below the fourth thoracic spinal cord segment. Although it is difficult to identify the pathognomonic morphological changes responsible for the sphincter dysfunction, the present case suggests a supranuclear dysregulation of the somatosensory and central autonomic nervous systems involved in urination and defecation. Based on a review of the literature and the features of the present case, paraganglioma can metastasize aggressively even with a low pathological grading. This case of vertebral metastasis as a result of malignant paraganglioma may not be extraordinary but the autopsy report is rare. This autopsy revealed transverse myelopathy as a result of malignant vertebral metastasis of malignant paraganglioma.

Simple and complex carotid paragangliomas. Three decades of experience and literature review

BACKGROUND

Carotid paragangliomas are rare tumors. They are usually unique, non-secreting, resectable, and benign. However, additional rare cases of complex tumors (bilateral, secretory, nonresectable, or malignant) complicate the management and final outcomes.

METHODS

Records of paragangliomas from our hospital are reviewed. Criteria defining complex paragangliomas have been previously defined. These are compared with those of the simple group.

RESULTS

Fifty patients, two groups: simple (n = 39) and complex (n = 11). The patients in the complex group were significantly younger (47.7 vs 63.8 years). Postoperative nerve complications (45.4% vs 6.3%) and mortality during follow-up (27.3% vs 0%) were significantly more common in the complex group. Vascular complications (0% vs 3.1%) and early mortality (0%) were similarly in both groups.

CONCLUSIONS

Patients with complex carotid paragangliomas are heterogeneous. The former are younger, exhibit a high degree of diagnostic and therapeutic complexity, and have poorer morbidity and mortality. Surgical experience and interdisciplinary collaboration are essential.

Surgical treatment of malignant paraganglioma with spinal invasion in a juvenile patient: A case report

RATIONALE

Paragangliomas are rare neuroendocrine tumors that originate in specialized cells derived from the neural crest with metastasis to the thoracic spine being among the rarest forms. Here, we are presenting a detailed analysis of a case of malignant paraganglioma in the thoracic spinal region in a 14-year-old boy. Our focus is to emphasize the importance of considering malignant paraganglioma as a diagnosis and guiding the perioperative management upon surgical treatment. The management of these unique cases has yet to be well-documented.

PATIENT CONCERNS

A 14-year-old boy presented with a 5-month history of continuous and progressive elevated blood pressure and back pain. The patient, who had been diagnosed of malignant paraganglioma in the left posterior mediastinum for 3 months, received surgical resection of paraganglioma in the left posterior mediastinum, which had involved the left intervertebral foramen of T4. However, the tumor was not completely resected during the first operation.

DIAGNOSES

Magnetic resonance imaging of spine and positron emission tomography-computed tomography showed spinal cord compression secondary to the epidural component of the T4 mass, with increased marrow infiltration of the left T4 intervertebral foramen, which was difficult to be removed. Postoperative pathology confirmed the diagnosis of spinal involvement of malignant paraganglioma.

INTERVENTIONS

The patient underwent biopsy and percutaneous vertebroplasty of T4 and paravertebral lesions, and needle-track cement augmentation via a posterior approach.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 10-month follow-up visit. There were no other complications associated with the operation during the follow-up period.

LESSONS

Combined efforts of specialists from orthopedics, neurosurgery, thoracic surgery, and medical oncology led to the successful diagnosis and management of this patient. Malignant paraganglioma of thoracic spine, although rare, should be part of the differential diagnosis when the patient has a history of paraganglioma and presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the malignant paraganglioma when the tumor has caused neurological deficits. Osteoplasty by cement augmentation is also a good choice for surgical treatment. However, we need to take the potential risk of complications in bone cement applications into full consideration.

Bilateral malignant paragangliomas in a patient: a rare case report

BACKGROUND

Paragangliomas are neuroendocrine neoplasms that arise from the extra-adrenal paraganglia of the autonomic nervous system. Approximately 3% of all paragangliomas occur in the head and neck region. Most reported cases are benign and unilateral. We present here a rare case of bilateral malignant paragangliomas.

CASE DESCRIPTION

A 28-year-old woman presented to our department with a 10-year history of bilateral neck swelling. Physical examination showed bilateral neck masses with obvious pulsation. Enhanced CT revealed two irregular solid nodules, located in the left and right carotid artery bifurcation, respectively. Carotid artery angiography showed compression of the internal and external carotid arteries by the tumors on both sides. Upon diagnosis of the bilateral carotid body tumors, preoperative embolization was performed. The left-side lesion as well as the lymph nodes were resected and a diagnosis of malignant paraganglioma with lymph node metastasis was made. Genetic studies have shown that familial paragangliomas are associated with germline mutation of succinate dehydrogenase subunits SDHD on 11q23. She was treated with 50-Gy radiotherapy, and a subsequent CT scan performed two years later showed that the right-side lesion was unchanged. She was symptom-free as of the last follow-up.

CONCLUSIONS

The rarity of bilateral malignant paragangliomas makes their management clinically challenging. The primary management of a recognized malignancy should be directed toward complete surgical removal of the primary tumor and regional lymph nodes. Postoperative radiation is beneficial in slowing the progression of residual disease.

[A CASE OF MALIGNANT PARAGANGLIOMA OF THE URINARY BLADDER TREATED WITH CYCLOPHOSPHAMIDE, VINCRISTINE, AND DACARBAZINE CHEMOTHERAPY AND METAIODOBENZYLGUANIDINE THERAPY]

A 34-year-old man, diagnosed with paraganglioma of the urinary bladder, was referred to our hospital. Computed tomography showed a bladder tumor measuring 64 mm along with right obturator lymphadenopathy. Abnormal uptake was observed on ¹²³I-MIBG scintigraphy. The tumor was, therefore, diagnosed as malignant paraganglioma. We performed cystectomy, pelvic lymph node dissection, and neobladder reconstruction. Pathological examination revealed a malignant paraganglioma of the urinary bladder with right obturator lymph node metastasis. Postoperatively, both the uptake on ¹²³I-MIBG scintigraphy and catecholamine levels in blood and urine normalized. However, 22 months later, positoron emission tomography-computed tomography showed the presence of 2 recurrent tumors in the pelvis. The patient underwent 9 courses of cyclophosphamide, vincristine, and dacarbazine chemotherapy and MIBG radiotherapy twice, following which the tumor size decreased by 35% and catecholamine levels normalized once again. At about 2 years of follow-up, the patient was found to be free of recurrence.

Soft tissue metastasis of mediastinal non-functioning paraganglioma with unusual TTF-1 expression: a potential diagnostic pitfall

Metastatic extra-adrenal paragangliomas are very rare and can represent diagnostic challenges. We report a case of 69-year-old man with a tumor of the right shoulder. Histologic and immunohistochemical examinations confirmed the diagnosis of paraganglioma. Surprisingly, tumor cells were diffusely thyroid transcription factor 1 (TTF-1) positive. Succinate dehydrogenase complex subunit B (SDHB) deficiency has not been detected. Inherited syndromes associated with paragangliomas were ruled out. The primary tumor was identified in the mediastinum. This is the first report of TTF-1 expression in paraganglioma. To avoid misdiagnosis, careful clinical and pathological examination of any tumor with organoid growths pattern is necessary.

Predictors of malignancy in patients with pheochromocytomas/paragangliomas: Asian Indian experience

BACKGROUND AND AIMS

Malignant transformation of pheochromocytomas/paragangliomas (PCC/PGL) is a rare occurrence, and predictive factors for the same are not well understood. This study aims to identify the predictors of malignancy in patients with PCC/PGL.

MATERIALS AND METHODS

We performed a retrospective analysis of 142 patients with either PCC or PGL registered at our institute between 2000 and 2015. Records were evaluated for clinical parameters like age, gender, familial/syndromic presentation, symptomatic presentation, biochemistry, size, number and location of tumours and presence of metastases and mode of its diagnosis.

RESULTS

Twenty patients were found to have metastases; 13 had metastases at diagnosis and seven during follow-up. Metastases were detected by radiology (CT-neck to pelvis) in 11/20 patients (5/13 synchronous and 6/7 metachronous), ¹³¹I-metaiodobenzylguanidine in five (2/12 synchronous and 3/6 metachronous) patients and ¹⁸F-flurodeoxyglucose PET/CT in 15 (12/12 synchronous and 3/3 metachronous) patients. Malignant tumours were significantly larger than benign tumours (8.3 ± 4.1 cm, range: 3-22 cm vs 5.7 ± 2.3 cm, range: 2-14 cm, P = 0.0001) and less frequently metanephrine secreting. On linear regression analysis, tumour size and lack of metanephrine secretion were the independent predictors of malignancy.

CONCLUSIONS

Patients with primary tumour size >5.7 cm and lack of metanephrine secretory status should be evaluated for possible malignancy not only at diagnosis but also in the postoperative period. As compared to CT and ¹³¹I-MIBG scan, ¹⁸F-flurodeoxyglucose PET/CT analyses are better (sensitivity: 100%) for the diagnosis of metastases in our study.

Long clinical benefit achieved in two patients with malignant paraganglioma treated by metronomic cyclophosphamide

Treatment of malignant paraganglioma remains a challenge with an overall 5-year survival rate between 34 and 60%. Systemic treatment is recommended in case of unresectable malignant paraganglioma. Recent advances in molecular biology provided rationale to use antiangiogenic agents in this setting. Metronomic cyclophosphamide could be efficient by antiangiogenic effect and immune stimulation with a good safety profile. Here, we report two cases of malignant paraganglioma in frail and symptomatic patients, achieving a long-term clinical benefit with such regimen, after progression or toxicity with sunitinib.