A case of an unexpected posterior mediastinal functional paraganglioma: case report and literature review

Neurogenic tumours of the posterior mediastinum and differential diagnosis considerations

The mediastinal compartment harbours vital organs and structures, including the heart, great vessels, major airways, and thymus. These structures are embedded in and associated with soft-tissue elements consisting of adipose and fibro-collagenous tissue in which soft-tissue tumours may develop. A detailed inventory of soft-tissue tumours that may be encountered in the mediastinum based on the WHO 2013 classification was published in 2015. In addition, several comprehensive reviews on mediastinal soft-tissue pathology are available, including reviews focusing specifically on a single tumour type. This review will focus on primary neurogenic and spindle cell tumours of the somatic soft tissue of the posterior mediastinum and provide a discussion of the pertinent differential diagnoses.

Middle mediastinal paraganglioma: A case report and review of the literature

RATIONAL

Paragangliomas are rare and can occur in many places throughout the body, but mediastinal paragangliomas are even rarer, accounting for less than 0.3% of mediastinal masses. Extremely susceptible to misdiagnosis and mistreatment, which may lead to the death of the patient.

PATIENT CONCERNS

We report a case of a giant paraganglioma of the middle mediastinum. A 40-year-old woman was admitted to the hospital with a rib fracture and a chest computed tomography suggesting a giant occupying tumor in the middle mediastinum.

DIAGNOSIS

Immunohistochemistry revealed positive for S100 fraction and Syn, focally positive for CgA, while negative for CKp and succinate dehydrogenase complex iron sulfur subunit B gene, and Ki67index ≈ 5%. The imaging and immunohistochemical features suggested a final diagnosis of Paragangliomas.

INTERVENTIONS

This patient underwent lateral open heart surgery to remove a mediastinal mass.

OUTCOMES

One month after being discharged, the patient was contacted by phone for a follow-up visit and reported feeling OK. Unfortunately, as of the date of submission, the patient did not come to our hospital for review.

LESSONS

Mediastinal paraganglioma as a rare and potentially malignant tumor susceptible to misdiagnosis and mistreatment. Organ pathology examination is the gold standard for diagnosis, and surgery is an important treatment method. A clear diagnosis and thorough preoperative examination are important guarantees for the success of surgery.

Paraganglioma of the anterior superior mediastinum: Presentation of a case of mistaken diagnosis so long and review of the literature

INTRODUCTION AND IMPORTANCE

Mediastinal paraganglioma is a rare tumor with neuroendocrine activity, highly susceptible to misdiagnosis. Herein, we present a case misdiagnosed as Castleman disease for nearly a decade, significantly enlarged, lost the opportunity of thoracoscopic surgery, and was removed by median thoracotomy.

CASE PRESENTATION

A 59-year-old woman complained of having a mediastinal mass, was diagnosed with Castleman disease for nearly a decade and was admitted to the hospital due to neck tightness. The tumor size was significantly enlarged. We proceeded to interventional angiography with gelatin sponge angioembolization, and the tumor was resected through a median sternotomy on the second day. The operation was smooth, and the tumor was gray and slightly brittle. Postoperative pathology confirmed paraganglioma; lymph node metastasis was not detected (0/3).

CLINICAL DISCUSSION

Mediastinal paraganglioma is a rare tumor and can be either functional or nonfunctional. It can be differentiated from many diseases. The SSTR-PET-CT labeled with 68Ga-somatostatin analog, plasma metanephrine, and normetanephrine are essential for the diagnosis. Surgical resection is the most effective form of treatment. Pre-operative embolization of the feeding artery is considered to have a low rate of intraoperative bleeding. We recommend making comprehensive preparations to ensure perioperative safety and long-term survival.

CONCLUSION

When a vascularized mass is discovered in the mediastinum, surgeons should consider the possibility of a paraganglioma. Multidisciplinary consultation should be involved in the formulation of treatment plans. Lifelong surveillance for residual tumor growth and recurrence is required.

Anesthetic management of patients undergoing mediastinal mass operation

Objectives

To summarize the anesthetic management of patients undergoing mediastinal mass operation.

Methods

Electronic databases were searched to identify all case reports of patients undergoing mediastinal mass operation. Information such as clinical characteristics, perioperative management and patients’ outcomes were abstracted and analyzed.

Results

Seventy-seven case reports with 85 patients aging from 34 days to 81 years were included. Mediastinal masses were located in anterior (n = 48), superior (n = 15), middle (n = 9) and posterior (n = 9) mediastinum, respectively. Clinical manifestations included dyspnea (n = 45), cough (n = 29), chest or radiating pain (n = 12), swelling (n = 8), fever (n = 7) and chest distress (n = 4). Most patients (n = 75) had signs of compression or invasion of vital structures. General anesthesia (n = 76) was the most commonly used method of anesthesia. Muscle relaxants were administered in 35 patients during anesthesia induction and spontaneous respiration was maintained in 37 patients. Mediastinal mass syndrome (MMS) occurred in 39 cases. Extracorporeal circulation was utilized in 20 patients intraoperatively. Three patients experienced cardiac arrest after ventilation failure and two patients died intraoperatively and one postoperatively.

Conclusions

Peri-operative management of patients undergoing mediastinal mass operation could be challenging. Pre-operative multi-disciplinary discussion, well-planned anesthetic management and pre-determined protocols for emergency situations are all vital to patient safety.

Middle mediastinal paraganglioma enclosing the left anterior descending artery: A case report

RATIONALE

Paragangliomas are extremely rare neuroendocrine tumors arising from ganglia. These tumors are barely found in the middle mediastinum.

PATIENT CONCERNS

A 31-year-old male patient was admitted to our hospital for treatment of an middle mediastinal tumor which was found incidentally on echocardiography during a medical checkup. Contrast-enhanced chest computed tomography (CT) demonstrated a well-defined hypervascularized heterogeneous mass located in the middle mediastinum. The tumor showed strong 18F-fluorodeoxyglucose (FDG) activity on positron emission tomography-computed tomography (PET-CT).

DIAGNOSIS

Before the surgery, we presumed the mass was an angiogenic or neurogenic tumor. As a result, the histological features favored a diagnosis of paraganglioma.

INTERVENTIONS

The tumor was completely removed by anterior thoracotomy, along with the proximal segment of the left anterior descending artery (LAD), and coronary artery bypass grafting (CABG) was performed immediately after the tumor excision.

OUTCOMES

The patient had an uneventful recovery. The patient did well in the postoperative follow-up without any complications and signs of recurrence at 3 months, 1 year, 2 year and 4 year.

LESSONS

This report can increase the confidence in surgeries of mediastinal paragangliomas adhering tightly the adjacent structures.

Pulmonary artery transection for resection of a middle mediastinal paraganglioma

We report the case of a 65‐year‐old male patient who presented with chest pain and was found to have a mediastinal paraganglioma between the left atrium and main pulmonary artery. This is the first reported case of a mediastinal paraganglioma resection utilization transection of the main pulmonary artery.

Paraganglioma with highly malignant potential involving the rib - Case report and review of the literature

Paragangliomas are rare neuroendocrine tumors arising from paraganglion cells in sympathetic or parasympathetic chains, which may develop in the abdomen, chest, skull base, and neck. As paragangliomas have a wide range of imaging features, the diagnosis often requires tissue sampling. We present a unique case of a paraganglioma which originally presented as a rib tumor.

A 64-year-old male with right flank pain for 2 months’ was referred for a noncontrast renal colic CT. He was found to have a 3.7 × 3.5 cm soft tissue mass invading the left posterior 9th rib and paraspinal muscle. This was fluorodeoxyglucose F 18, (¹⁸F-FDG) avid, with no other distant metabolic activity. He underwent ultrasound-guided core biopsy which revealed a diagnosis of paraganglioma. A right thoracotomy with chest wall resection of 8, 9, and 10 ribs were subsequently performed. The tumor was removed along with a small portion of adherent lung. The tumor was positive for CD56, synaptophysin and chromogranin. S-100 highlighted occasional sustentacular cells, consistent with a pathologic diagnosis of a paraganglioma. The patient remains symptom free for 6 months’ after the operation.

Our case highlights that, when paragangliomas occur within the chest wall, they may present as a rib tumor and can mimic metastasis, myeloma or other primary neoplastic etiologies originating from ribs. Both imaging and pathologic diagnosis can be challenging.