Study Describes 12 Cases of Lung Cancer in Women With Scleroderma
Detailed characteristics of 12 cases of lung cancer in people with scleroderma were described in a new study. Notably, all patients were women and most had interstitial lung disease (ILD).
The study, “Clinicopathological characteristics of lung cancer in patients with systemic sclerosis,” was published in The Clinical Respiratory Journal.
Previous research has demonstrated that scleroderma, also called systemic sclerosis, is associated with an increased risk of cancer, including lung cancer. Detailed analyses of cases of lung cancer in people with scleroderma may provide insights into both diseases, how they interact, as well as treatment records.
Here, researchers analyzed medical records from the Peking Union Medical College Hospital in China. Of 838 people with scleroderma admitted to the hospital from 2000 to 2017, 12 (1.4%) were diagnosed with lung cancer and had available medical records. This prevalence was “clearly higher than the reported prevalence in the general Chinese population,” the scientists wrote.
All patients were women and non-smokers. Notably, a prior study in China indicated an increasing overall prevalence of cancer in women and also showed that lung cancer is the most common type in women 60 and older. Yet, men have shown a consistently higher prevalence of lung cancer.
The lung was affected in eight cases, most often manifesting as ILD. One of the patients had pulmonary artery hypertension. The esophagus was affected in the remaining four patients.
All patients received glucocorticoids. Six received methotrexate, four received cyclophosphamide, and two received CellCept (mycophenolate mofetil).
On chest imaging, common findings included nodules, enlarged lymph nodes, thickening of the pleura — two layers surrounding the lungs — and bronchiectasis.
In nine cases, lung cancer was diagnosed following worsening symptoms, namely more severe shortness of breath, exacerbated coughing, and weight loss. In two cases, diagnosis occurred due to incidental findings on lung imaging. The remaining case involved a growing lung nodule.
The most frequent type of lung cancer was adenocarcinoma, diagnosed in nine cases. Squamous cell carcinoma and small cell carcinoma were found in one patient each. In the remaining case, the type of lung cancer was not identified.
Five of the women with adenocarcinoma underwent genetic analysis. No patient had driver mutations, which promote cancer development.
“The predominance of female patients and the absence of smoking history in our cohort suggested an independent role of SSc itself in the development of lung cancer. This is further supported by the lack of common driver mutations in the female patients without smoking history,” the researchers wrote.
According to the team, the fact that ILD was not present in four patients “suggested that pulmonary fibrosis is not a precondition for cancer development.”
In four cases, the cancer was treated with surgery. Eight women received chemotherapy and one was treated with radiotherapy. No high-grade adverse events (side effects) were reported.
The main limitations of the study, the investigators said, included its small sample size and the absence of a control group with lung cancer patients without scleroderma.