A rare case of solitary fibrous tumor of the pleura: An unusual presentation

INTRODUCTION

Solitary fibrous tumors of the pleura (SFTP) are rare mesenchymal neoplasms with a poorly recognized etiology and highly variable presentations.

The most recognized signs and symptoms reported in the literature are chest pain, cough, and dyspnea.^[1] However, presentation with cardiac compression and subsequent hemodynamic instability due to mass effect is a rare occurrence. To date, only one such case has been reported in the literature.^[2]

This case report aims to describe an unusual presentation of SFTP, where the tumor mass effect resulted in significant lung collapse, mediastinal shift, and a deviated trachea, a presentation not previously reported in the literature.

CASE REPORT

A 69-year-old male presented with rapidly worsening symptoms, including breathlessness, productive cough, and weight loss. These symptoms significantly impacted the patient's daily activities. His medical history included idiopathic thrombocytopenic purpura (ITP), which had been managed conservatively for the past 15 years. He had no history of smoking or exposure to asbestos.

Initial physical examination revealed a deviated trachea, absent breath sounds on the left side of the chest, and signs of respiratory distress. Pulmonary function tests revealed severe impairment, with an FEV1 of 39% predicted and DLCO of 62% predicted, indicating significant respiratory compromise.

Investigation

Radiographic imaging revealed a giant pleural mass with a large pleural effusion, subtotal left lung collapse, and mediastinal shift. Figure 1 shows the initial radiograph obtained at presentation.

Close

Figure 1:

Radiographic imaging of a lung mass on presentation.

Export to PPT

A subsequent CT scan confirmed a large lesion with pleural effusion occupying most of the left pleural cavity, causing subtotal left lung collapse and mass effect on the heart [Figures 2 and 3].

Close

Figure 2:

Transverse cross-section CT scan of massive left-sided SFTP. CT: Computed tomography, SFTP: Solitary fibrous tumours of the pleura.

Export to PPT

Close

Figure 3:

Coronal cross-section CT scan of massive left-sided SFTP and pleural effusion. CT: Computed tomography, SFTP: Solitary fibrous tumours of the pleura.

Export to PPT

The PET-CT showed mild avidity of the lesion, suggesting local disease activity but no distant metastasis [Figure 4].

Close

Figure 4:

Coronal cross-section PET-CT scan of left-sided SFTP with mild avidity. PET-CT: Positron emission tomography and computed tomography, SFTP: Scan and solitary fibrous tumours of the pleura.

Export to PPT

A CT-guided biopsy was performed to aid diagnosis, and histology showed spindle cells with minimal cytological atypia, suggesting a solitary fibrous tumor.

The pleural fluid aspirate was blood-stained; however, cytology revealed no malignant cells. Cytology of the pleural fluid aspirate was negative for malignant cells.

Management

Due to the patient’s poor functional status, resulting from complete left lung collapse and mediastinal shift with associated hemodynamic compromise, major surgical resection was not initially feasible. As a result, a staged management approach was adopted.

First Stage: Decompression and Inspection

The patient underwent pleural decompression with an evacuation of 1000 ml of pleural effusion. This allowed for gross tumor inspection, which revealed a highly vascular mass attached to the upper lobe, the anterior mediastinum, and the parietal pleura. The pleura appeared thickened but not overtly malignant.

Pleural biopsies confirmed the gross findings. An indwelling catheter was placed to prevent further fluid accumulation and allow the lung to re-expand. The postoperative X-ray confirmed the re-expansion of the lung [Figure 5].

Close

Figure 5:

Post-operative X-ray following thoracoscopic evacuation of pleural effusion and insertion of indwelling pleural catheter.

Export to PPT

Second Stage: Surgical Resection

After 10 days, the patient showed significant clinical improvement and underwent second-stage resection. Due to the tumor’s massive size and its multiple pedicles of vascular supply, access to the chest cavity was challenging The tumour’s massive size and multiple vascular pedicles made access to the chest cavity technically challenging.

• Lateral parietal pleura

• Thick pedicle from an internal thoracic arterial branch at the superior mediastinum

• Thin pedicle next to the left phrenic nerve

• Thin pedicle from the aortopulmonary window

• Pericardial fat near the left ventricle of the heart

• Anterior segment and lingual of the upper lobe

A double-space thoracotomy was performed through the 4th and 7th intercostal spaces, providing adequate exposure for tumor resection. The tumor was dissected from the chest wall using extra-pleural dissection and from the lung via wedge resection of the upper lobe. All mediastinal pedicles were ligated, and the tumor was completely excised with adequate macroscopic margins (Postoperative radiograph is shown in Figure 6).

Close

Figure 6:

Chest X-ray post resection of tumor mass.

Export to PPT

Recovery and Follow-up

The patient had an uncomplicated recovery following the procedure and was discharged on postoperative day 7. His clinical condition picture improved rapidly. Within three months, the patient was able to resume day to day activities without pain or respiratory compromise.

Given the high recurrence rate of SFTP, the patient was scheduled for follow-up every six months for five years, with repeat CT scans. At the six-month follow-up, the CT scan revealed mild pleural thickening and some fluid anteriorly in the upper left hemithorax, but no signs of recurrence were detected [Figures 7-11].

Close

Figure 7:

Chest X-ray at 6-month follow-up.

Export to PPT

Close

Figure 8:

Transverse cross-section CT scan at the 6-month follow-up. CT: Computed tomography.

Export to PPT

Close

Figure 9:

Transverse cross-section CT scan at the 6-month follow-up. CT: Computed tomography.

Export to PPT

Close

Figure 10:

Transverse cross-section CT scan at the 6-month follow-up. CT: Computed tomography.

Export to PPT

Close

Figure 11:

Transverse cross-section CT scan at the 6-month follow-up. CT: Computed tomography.

Export to PPT

DISCUSSION

This case is unique in that it presents a SFTP causing bilateral lung collapse and tracheal deviation due to mass effect, which has not been reported in the literature to date. The only other case with a similar mass effect described an SFTP originating from the diaphragm, leading to compression of the pericardium and other mediastinal structures.^[2]

The size of the tumor is often correlated with its malignant potential, with larger tumors generally considered at higher risk of malignancy^[1]. In our case, despite the large tumor size and associated mass effect, neither the gross appearance nor fluid cytology suggested malignancy. Histopathology and immunohistochemistry were also inconclusive regarding malignant potential.

Complete resection of SFTPs is considered the best management strategy, with an excellent prognosis for benign tumour variants. Surgical resection has also been shown to prolong survival in malignant cases^[3,4]. In this case, due to the massive size of the tumor, a two-stage surgical approach was required. Video-assisted thoracoscopic surgery (VATS) has been successfully used for tumors of up to 15 cm in diameter^[3], but in this case, the tumor’s size necessitated an open surgical approach.

CONCLUSION

SFTP is a rare and usually benign tumor, but it can present in ways that are potentially life-threatening if not diagnosed early. While tumor size is commonly used as a predictor of malignancy, clinical and radiological features alone are unreliable for distinguishing between benign and malignant variants. In cases of advanced disease with significant mass effect, open surgical resection may be required, as opposed to less invasive techniques such as VATS. Given the potential for recurrence, long-term follow-up is crucial for monitoring tumor regrowth.