Pneumothorax during Pazopanib Treatment in Patients with Soft-Tissue Sarcoma: Two Case Reports and a Review of the Literature

Being the ultimate travel companion of a patient with uterine leiomyosarcoma

Uterine fibroids are difficult to distinguish from malignant masses using standard ultrasonography; and morcellation carries the risk of disseminating occult cancer in a small but relevant group of women with an undetected uterine malignancy. In this context, we follow the progress of a woman diagnosed with uterine leiomyosarcoma after suboptimal initial surgery for an assumed fibroid. Evidence is reviewed that guided multidisciplinary tumor board decisions about optimal management approaches after local seeding and development of distant metastases, and informed treatment selection at each line of therapy. As the case study illustrates, choice of treatment for advanced soft tissue sarcomas frequently involves finding an appropriate balance between the efficacy and toxicity of available options, aiming to allow patients to maintain their normal lives.

Different patterns of pneumothorax in patients with soft tissue tumors treated with pazopanib: A case series analysis

To investigate pneumothorax patterns in pazopanib treatment by focusing on the positional relationship between the visceral pleura and metastatic lung tumor, we examined 20 patients with advanced soft tissue tumors who developed lung metastases and underwent pazopanib treatment between 2012 and 2019. Pneumothorax was classified into two types based on the location of the metastatic lesion around the visceral pleural area before pazopanib treatment: subpleural type, within 5 mm from the pleura; and central type, >5 mm from the pleura. We investigated the rates of pneumothorax and the associated risk factors. Five patients experienced pneumothorax (three subpleural and two central types). Cavitation preceded pneumothorax in 83% of patients and led to connection of the cavitated cyst of the metastatic lesion to the chest cavity in the shorter term in patients with the subpleural type. Conversely, a more gradual increase in the cavity size and sudden cyst rupture were observed in the central type. The risk factors for pneumothorax were cavitation after initiating pazopanib and intervention before pazopanib, either ablation or surgery. The location of the metastatic lesions was not a risk factor for the occurrence of pneumothorax. In conclusion, pneumothorax is an adverse event associated with pazopanib treatment. Therefore, attention must be paid to predisposing factors such as the formation of cavitation after pazopanib initiation and previous interventions to the lungs. Moreover, because subpleural pneumothorax tends to occur earlier than the central type, a different time course can be anticipated based on the positional relationships of the metastatic lesions to the visceral pleura.

Postmarketing observational study of pazopanib in patients with metastatic soft tissue sarcoma in Japan

BACKGROUND

This study evaluated the safety and efficacy of pazopanib in patients with metastatic soft tissue sarcoma in routine clinical use in Japan.

METHODS

It was a multicentre, centrally registered and uncontrolled observational study in patients who received pazopanib for metastatic soft tissue sarcoma, with an observation period of 1 year after the start of drug administration. The study was conducted at 378 investigational sites in Japan from September 2012 to September 2019. Progression-free survival (PFS) and overall survival (OS) were the efficacy endpoints of the study.

RESULTS

A total of 1970 patients were enrolled. Of these, 680 with finalized study forms were included in the analysis. Overall, 649 patients were included in the safety analysis set, and 569 were included in the efficacy analysis set. Most of the patients (81.97%) experienced at least one adverse drug reaction (ADR); 22.34% of patients reported serious ADRs and 34.98% of patients experienced grade ≥ 3 ADRs in the safety set. Hypertension (40.37%) and hepatic dysfunction (26.50%) were the two most common ADRs. A total of 262 deaths were reported, of which 12 were due to ADRs. The median PFS was 3.09 months, whereas the median OS was not reached at the end of the 1-year observation period.

CONCLUSIONS

The safety and efficacy profiles in this postmarketing observational study were consistent with prior data and registration clinical trials. No new safety signals were observed while treating patients with metastatic soft tissue sarcoma with pazopanib.

Tension Pneumothorax: Is it Sarcoma or Pazopanib?

Synovial sarcomas are rare malignant tumors that originate from primitive pluripotent mesenchymal stem cells that look similar to the developing synovium, but are histologically unrelated to it. Sarcomas commonly metastasize to the lungs and surrounding pleura, with a documented incidence as high as 85% for pleural-based metastases. The incidence of spontaneous pneumothorax in patients with sarcomas is only 1.9%, with synovial sarcoma being the third most common type of sarcoma associated with pneumothorax. While surgical resection is usually the treatment for localized primary synovial cell sarcoma, metastatic disease requires systemic therapy, mainly chemotherapy. Failure of chemotherapy calls for the use of targeted therapeutic agents such as pazopanib. Pazopanib has been linked to the incidence of spontaneous pneumothorax in previous case studies. However, primary research fails to establish a statistically significant causal association. Research shows that pneumothorax can result from lung metastases independent of therapeutic side effects. We report a case of synovial sarcoma of trapezius origin with secondary lung metastases, and development of pneumothorax after pazopanib treatment. We discuss the incidence of pneumothorax as a medication side effect versus independent effect of natural disease progression, and how this plays role in deciding when to continue using a medication in the face of complications.

Pneumothorax triggered by EGFR-tyrosine kinase inhibitors in three microwave ablation candidates: A review of the literature

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are widely used in patients with EGFR‐mutant lung cancer. Meanwhile, thermal ablation such as microwave ablation has been an option for selected patients. Herein, we describe three cases of pneumothorax that occurred in microwave ablation (MWA) candidates treated with EGFR‐TKIs. The three patients developed pneumothorax in different periods: case 1 developed pneumothorax two months after MWA and subsequent gefitnib therapy; case 2 took osimertinib for two years and developed pneumothorax before MWA; case 3 took gefitinb for 13 months and experienced bronchopleural fistula after MWA. Although a causal relationship is uncertain, the risk of pneumothorax for these MWA candidates should be considered.

Key points

Microwave ablation candidates treated with epidermal growth factor receptor tyrosine kinase inhibitors are more likely to suffer pneumothorax.

The risk of delayed pneumothorax or even bronchopleural fistula in patients pretreated with tyrosine kinase inhibitors should be taken into consideration when selecting patients and performing microwave ablations.

Pazopanib-induced organizing pneumonia in a patient with leiomyosarcoma: A case report

Pazopanib, a multityrosine kinase inhibitor used for treating malignant soft tissue tumors, rarely causes adverse events associated with the respiratory system. We report a case of a 73-year-old male with leiomyosarcoma treated with pazopanib. Four months after treatment initiation, chest computed tomography showed bilateral patchy consolidation and ground-glass opacities. Bronchoscopy revealed increased lymphocytes in the bronchoalveolar lavage fluid. Histological analysis of lung tissue demonstrated intraluminal fibrotic changes in alveolar spaces. According to these findings, we diagnosed the patient with pazopanib-induced organizing pneumonia. To best of our knowledge, this is the first report of such a case.

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Pazopanib is a multityrosine kinase inhibitor used for treating soft tissue tumors.

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Pazopanib rarely causes adverse events associated with the respiratory system.

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This is the first report of a patient with pazopanib-induced organizing pneumonia.

A Case of Pneumothorax after Treatment with Lenvatinib for Anaplastic Thyroid Cancer with Lung Metastasis

A 63-year-old man was diagnosed with multiple lung metastases from anaplastic thyroid cancer and received lenvatinib. Follow-up computed tomography on day 34 of lenvatinib treatment showed pneumothorax. The pneumothorax was temporarily improved with chest drainage. However, pleurodesis was performed to treat a relapse of the pneumothorax. Pneumothorax during chemotherapy for a malignant tumor is considered a relatively rare complication. This case is the first documentation that pneumothorax may develop during lenvatinib treatment. The possible development of pneumothorax should be considered when lenvatinib is used in patients with lung metastasis.