Head and neck paragangliomas: physiology and biochemistry

Head and Neck Paragangliomas: Overview of Institutional Experience

Head and neck paragangliomas (HNPGLs) are rare and have high rates of genetic mutations. We conducted a retrospective review of 187 patients with 296 PGLs diagnosed between 1974 and 2023. The mean age of diagnosis was 48.8 years (range 10 to 82) with 69.0% female and 26.5% patients with multiple PGLs. Among 119 patients undergoing genetic testing, 70 (58.8%) patients had mutations, with SDHB (30) and SDHD (26) being the most common. The rates of metastasis and recurrence were higher among patients with SDHB mutations or SDHD mutations associated with multiple PGLs. Metabolic evaluation showed elevated plasma dopamine levels were the most common derangements in HNPGL. MRI and CT were the most common anatomic imaging modalities and DOTATATE was the most common functional scan used in this cohort. Most patients (81.5%) received surgery as the primary definitive treatment, while 22.5% patients received radiation treatment, mostly as an adjuvant therapy or for surgically challenging or inoperable cases. Systemic treatment was rarely used in our cohort. Our single-center experience highlights the need for referral for genetic testing and metabolic evaluation and for a team-based approach to improve the clinical outcomes of patients with HNPGLs.

Paragangliomas of the head and neck

Paragangliomas are rare neuroendocrine tumors that can be found from the skull base to the pelvis. Head and neck paragangliomas have been historically treated with surgery. However, surgical resection adds risk of injury to vascular structures and cranial nerves that can lead to morbidity such as hoarseness, dysarthria, dysphagia, or aspiration. Recently, improved understanding of the behavior of these tumors and increasing experience in non-surgical treatments such as observation and radiation therapy, have changed the paradigms of management of this entity. Multiple series now show a trend towards a more conservative management, with a higher percentage of patients being observed or treated with radiotherapy. Several factors should be taken into consideration when deciding the most appropriate treatment for head and neck paragangliomas, starting by differentiating carotid body tumors from non- carotid body tumors. In general, surgical resection is normally recommended for carotid body tumors as the complications from treatment are usually minimal. In contrast, for non- carotid body tumors, surgery is often associated with significant functional impairment due to cranial nerve paralysis. As such, non-surgical treatment is now usually recommended for this subset of head and neck paragangliomas. In young patients with no comorbidities and a small to medium carotid body tumors, surgery should be considered. Moreover, surgery should be offered for secreting tumors, malignant tumors, tumors with rapid growth or increase in symptomatology, and when radiotherapy cannot be performed. Conversely, conservative management with active surveillance or radiotherapy can be offered in the remaining cases in order to avoid unnecessary morbidity while still providing acceptable tumor control.

Sudden Death Due to Neck Paraganglioma: A Pediatric Case Report and Review of the Literature

Neck paragangliomas are relatively rare neuroendocrine nonsecretory tumors. They are mainly observed among adults and are often asymptomatic, causing a frequent delay in diagnosis. In pediatric cases, neck paragangliomas can be associated with adrenergic symptoms that may lead to complications.A report of a sudden death due to a carotid paraganglioma in a young girl is reported. Autopsy revealed a thoracic arotic dissection and a 4-cm jugulocarotidian mass in the absence of traumatic injuries. Histology showed no evidence of underlying aortic disease, including signs of Marfan syndrome, and a paraganglioma. Postmortem biochemistry analysis showed blood metanephrines levels 100 times higher than normal range. The cause of death was an aortic dissection complicating a neck paraganglioma. The manner of death was concluded as natural.Our case highlighted the importance for forensic pathologist to consider the diagnosis of paraganglioma in case of sudden hypertensive complications, especially among young people.

Head and neck paragangliomas: 30-year experience

BACKGROUND

We aimed to review our experience and the changing trends in the management of head and neck paragangliomas (HNPG) over the last three decades.

METHODS

We retrospectively reviewed 103 patients with HNPG treated at our center (1986-2017). We included patients treated with surgery, radiotherapy, and patients maintained under active surveillance.

RESULTS

Of the surgically treated patients (n = 79), 20% (12/59) of the carotid body tumors (CBT) had a cranial nerve deficit as sequela compared to 95% (19/20) of the non-CBT. Radiotherapy controlled growth in all tumors treated with this modality (n = 10). Of the initially observed patients, 70% (14/20) remained stable and did not require additional treatment. Stratifying by decades, there was a progressive increase in patients initially attempted to be observed and a decrease in upfront surgery. No deaths attributable to the HNPG were encountered.

CONCLUSIONS

Surgery is an effective treatment for CBT. Nonsurgical treatment should be considered for non-CBT.

Orbital Paraganglioma in Infancy: Does It Behave More Aggressively?

BACKGROUND

Paragangliomas of the head and neck region are not only rare but also unique in that they are derived from the parasympathetic system and are nonsecretory. Orbit represents 1 of the least common sites for head and neck paragangliomas. Orbital paraganglioma remains predominantly a disease of adults, and it has never been reported in infancy earlier. Therefore it is not known if these tumors in infancy behave any differently than their adult counterparts.

CASE REPORT

A 1-year-old boy presented with left-sided proptosis and restricted ocular movement for 3 months. On examination, the proptosis was nonaxial and nonreducible and the child could follow objects with the left eye with normal pupillary reactions bilaterally. On neuroimaging, a rounded enhancing mass was seen in the superomedial aspect of the left retrobulbar space closely abutting the optic nerve. The tumor was subtotally excised using a left fronto-orbital approach, leaving some tumor on the optic nerve. It was decided to closely observe the residual tumor in the follow-up period; however, the child developed recurrence with visual loss after 6 months of surgery.

CONCLUSION

Orbital paraganglioma in infancy may be more aggressive than the adult counterparts. Although simple excision without adjuvant radiation may be tried in localized tumors with intact vision, recurrence tends to be high. Orbital exenteration with or without radiotherapy remains the only salvage option in such recurrences.

Diagnosis and management of multiple paragangliomas of the head and neck

Paragangliomas (PGs) are slowly growing, usually benign neoplasms. The aim of the study was to analyze the incidence, diagnostic and therapeutic management of patients with multiple paragangliomas of the head and neck. A retrospective review of the records of 84 patients with head and neck PGs, diagnosed and treated in our institution was performed for the years 1983-2013 to identify patients with multiple tumors. Fourteen (16.6 %) patients developed multiple PGs, synchronous or metachronous, within 4-21 years of follow-up. Clinical data of these patients were reviewed to evaluate the diagnosis, location, stage and management strategy. There was a total number of 37 tumors in 14 patients. There were 20/37 (54.0 %) carotid PGs, 9/37 (24.3 %) jugular PGs and 8/37 (21.7 %) vagal PGs. Carotid PGs were observed in 12/14 (86 %) patients and in 8/14 (57 %) cases bilateral tumors occurred. Vagal PGs developed in 7/14 (50 %) patients and bilateral tumors were found in 1/14 (7 %) case. Jugular PGs occurred in 9/14 (64 %) patients. There were 30 synchronous tumors and seven metachronous PGs diagnosed 2-18 years after removal of the first tumor. Single metachronous mediastinal PG occurred. All patients had at least one tumor removed, with histopathological confirmation of the diagnosis. One patient had positive history of familial PGs. Carotid PGs are most common multiple paragangliomas. Radiological survey of the head and neck is required to detect multicentric tumors. Metachronous mediastinal and abdominal tumors may occur. Regular, prolonged follow-up is essential to identify metachronous PGs and possible postoperative gradual ICA occlusion.

Orbital paraganglioma presenting as lateral rectus enlargement and its novel management: a case report and review of literature

Paragangliomas of the orbit are extremely rare. We report on a case of paraganglioma manifesting as enlargement of the lateral rectus muscle. Magnetic resonance imaging (MRI) of the orbit showed typical salt and pepper appearance of the mass and pathologic examination was consistent with paraganglioma. The patient underwent surgery with total removal of lateral rectus muscle. Alignment was preserved by a half tendon transposition of the vertical rectus muscles to the insertion of the resected lateral rectus muscle. Isolated lateral rectus enlargement has not been previously reported as a manifestation of paraganglioma.

The Role of Radiotherapy in the Management of Paraganglioma

Paragangliomas or glomus tumors are usually low-grade hypervascular tumors occurring in various sites of the autonomic nervous system including the carotid body, glomus vagale and glomus tympanicum. Although the grading of the tumor suggests a benign clinical course, the tumor can be locally malignant and surgical management is sometimes difficult because of postoperative functional loss and local recurrence. In addition, the operative field is generally very bloody and tissue planes are not always well-defined.

Though the optimal management of paraganglioma occurs in a multidisciplinary setting, considering the excellent local control rates with primary irradiation alone, a nonsurgical definitive approach should initially be considered.

A rare case of paraganglioma of the sella with bone metastases

Sellar paragangliomas are very rare lesions with only 11 previous cases described in the literature. We present a further case of sellar paraganglioma. The patient is a 17-year-old man who developed headache, visual blurring, and diplopia. MRI showed a sellar lesion. Trans-nasal trans-sphenoid biopsy showed features of paraganglioma. He was treated by Stereotactic radiotherapy. Four months after treatment he developed bone metastases which was palliated by radiation, zoledronic acid, and chemotherapy. This is the first case of sellar paraganglioma showing metastases to bone.

[Diagnostic evaluation of temporal paragangliomas]

Paragangliomas are rare tumours deriving from paraganglia--small bodies of neuroendocrine tissue. Approximately 3% of paragangliomas occur in the head and neck area accounting for about 0,6% of all tumours of this region. Head and neck paragangliomas are divided into two groups: neck tumours (carotid body tumor and vagal paraganglioma) and temporal paragangliomas (jugular bulb tumor and tympanic paraganglioma). Temporal paragangliomas arise from paraganglia located in the petrous part of the temporal bone. Radiological evaluation of these lesions is essential for confirming the diagnosis and surgery planning. Most useful methods are magnetic resonance imaging and computed tomography. These modalities deliver important information about tumour location, extension and the state of the surrounding structures. Carotid angiography is a second step diagnostic method, performed in patients with jugular bulb paraganglioma. It has a diagnostic value and allows palliative or preoperative embolization of the tumor. Ultrasonographic evaluation and scintigraphy also provide advantages in diagnostic management.

Skull base surgery for removal of temporal bone tumors

CONCLUSION

When selecting the appropriate surgical approach the pathological type of tumor, the physiological status as well as the functional aspects should be considered. Understanding the strengths and weaknesses of each surgical technique and knowledge of the particular tumor biology facilitates selection of the most appropriate surgical approach and a successful outcome.

OBJECTIVES

The purpose of this study was to review cases that underwent skull base surgery for a variety of tumors that involved the temporal bone. We reviewed a single center's 25-year experience for epidemiologic characteristics, symptoms, treatment type and outcomes.

PATIENTS AND METHODS

The medical records and radiological images of 91 patients, who underwent skull base surgery, were retrospectively reviewed.

RESULTS

Among the 91 patients, 61 cases had benign disease and 30 had malignancies. A facial nerve schwannoma was the most common benign intratemporal tumor and a squamous cell carcinoma was the most common malignant tumor. With the facial nerve schwannoma, facial nerve paralysis and hearing loss were the most common presenting complaints; otalgia was the most common presenting symptom for temporal bone cancer. For patients with a glomus tumor, there was a characteristic pulsating tinnitus. A majority of the facial nerve schwannomas were resectable through the transmastoid approach. The infratemporal fossa approach type A was usually required for lower cranial nerve schwannomas and glomus jugulare tumors. However, the fallopian bridge technique with hypotympanectomy was another surgical option. Partial temporal bone resection and subtotal temporal bone resections were performed in cases with temporal bone cancer. The disease free 5-year survival of the temporal bone cancers was 42% and for the squamous cell carcinomas, it was 44%.

Paraganglioma in sella

We report a very rare case of a paraganglioma arising from sellar and suprasellar region which has been treated with radiotherapy following multiple surgeries.

The basic science of glomus jugulare tumors

Glomus tumors are a fascinating group of lesions. It is a challenge for neurosurgeons and otolaryngologists to resect them completely with minimal morbidity. Laboratory researchers have discovered extremely interesting genetic and molecular biology factors involved in the development and growth of glomus tumors. In this article the author reviews the genetics, protein mutations, angiogenesis and apoptosis associated with tumor formation, and the secretion of vasoactive substances is discussed as well. It is hoped that with further research less invasive measures may be developed to treat these tumors.