A case of lung nodular aspergilloma mimicking tumor metastasis accompanied by pulmonary embolism in a gastric cancer patient in remission

Abstract

Lung aspergilloma is a noninvasive form of fungal infection of the Aspergillus species and usually presents radiologically as nodular masses in the lungs of patients with pulmonary tuberculosis, chronic obstructive pulmonary disease, and immunosuppressed patients. It may mimic lung metastatic nodules or primary lung cancer. A 57-year-old male patient who underwent surgery for stomach cancer was admitted to our hospital with complaints of shortness of breath, fatigue, and weight loss. Chest computed tomography scan revealed a new nodular lesion measuring 16 × 14 mm in diameter in the upper lobe of the right lung and an embolism in the left pulmonary artery. Wedge resection of the solitary pulmonary nodular was performed. After pathological evaluation, it was interpreted as aspergilloma. Here, we report a case of pulmonary aspergilloma that was followed up with the diagnosis of gastric cancer in remission and underwent resection due to the suspicion of lung metastasis.

Introduction

Gastric cancer is reported to be the fifth most common cancer worldwide in terms of both incidence and mortality. ¹ After gastric resections, deaths during follow-up are mostly due to distant metastases. ² Therefore, it is important to follow up with patients after surgery and adjuvant treatments for distant organ metastases. It has been reported that the survival of patients with gastric cancer is prolonged after resection of solitary nodular metastases in the lung. ³

In the English literature review, although few cases of pulmonary aspergillosis have been reported in solid tumor patients with a history of lung cancer and head and neck cancer,^4,5 no case of pulmonary aspergilloma have been reported in a patient with gastric cancer who was followed in remission and had no history of tuberculosis.

Here, we report a case of pulmonary aspergilloma that was followed up with the diagnosis of gastric cancer in remission and underwent resection due to the suspicion of lung metastasis. The patient is still under annual follow-up and is alive. Written informed consent was obtained from the patient.

Case presentation

A 57-year-old male patient was admitted to Medicana Beylikdüzü Hospital in April 2025, with complaints of shortness of breath, fatigue, and weight loss. The patient had a history of total gastrectomy plus D2 lymph node dissection operation for well-differentiated gastric adenocarcinoma in March 2017. Pathologic staging was evaluated as pT3N0M0. After the operation, he received concurrent radiochemotherapy with capecitabine and then a single drug, capecitabine, for a total of 6 months.

The patient underwent a physical examination, and comprehensive blood tests were ordered, including tumor markers, complete blood count, D-dimer, and liver and kidney function tests. Additionally, a computed tomography (CT) scan was requested. The results of the blood tests are as follows: white blood cell count—7580/μL; neutrophils—5360/μL; hemoglobin—12.7 g/dL; platelet count—177 × 10³/μL; CA 72.4 level—1.08 U/mL (normal range: 0–6.9); blood urea nitrogen—26 mg/dL; creatinine—0.77 mg/dl; blood glucose—89 mg/dl; HbA1c—5.88% (4–6 normal limits); carcinoembrionic antigen (CEA) level—4.18 ng/mL (normal limits: 0–3.4 nonsmoker); carbohydrate antigen (CA 19–9) level—13.96 U/mL (normal range: 0–37); C-reactive protein—0.41 mg/dL; D-dimer— 996 ng/mL (normal limits: 0–500). In addition, other biochemical and complete blood count tests were normal.

Chest CT scan revealed filling defects consistent with embolism in the anterobasal segment branches of the left lower lobe pulmonary artery and a new nodular lesion measuring 16 × 14 mm in diameter in the upper lobe of the right lung. A biopsy using endobronchial ultrasound was not feasible. A CT-guided biopsy was deemed to carry a risk of pneumothorax. A whole-body ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET)/CT scan was performed due to the anticipated complication of CT-guided biopsy. ¹⁸FDG PET/CT imaging revealed a 16 × 14 mm nodular mass with a high uptake (standardized uptake value (SUV) max: 12.5) in the apical zone of the upper lobe of the right lung (Figure 1). Enoxaparin (6000 U, 2 × 1) was administered subcutaneously for the treatment of pulmonary embolism. The patient’s dyspnea improved after 2 weeks of anticoagulant treatment. Anticoagulant treatment was continued for at least 3 months. A multidisciplinary evaluation was conducted at our hospital’s tumor board, and it was decided to remove the tumor via surgical resection. The patient was referred to a thoracic surgeon due to a nodular mass on an ¹⁸FDG PET/CT scan. Wedge resection of the solitary pulmonary nodular mass was performed. In histopathological examination, a lesion involves a discrete nodule consisting of a well-demarcated and round-shaped fungus ball in which numerous hyphae are aligned in a radial pattern (Figure 2). After pathological evaluation, it was interpreted as aspergilloma. The blood galactomannan test was negative. There was no evidence of tuberculosis or fungal growth in the sputum culture. No additional antifungal treatment was recommended by the infectious diseases specialist after surgery. The patient remains in remission and returns for a control examination once a year.

Figure 1.

¹⁸FDG PET/CT imaging revealed a 16 × 14 mm nodular mass with a high uptake (SUV max: 12.5) in the upper lobe of the right lung (white arrow).

Figure 2.

Fungus focus composed of hyphal elements of Aspergillus. Branching, septate hyphae are close-packed and radiating outward in this aspergilloma (hematoxylin–eosin, ×100).

Discussion

Aspergilloma is a noninvasive form of chronic pulmonary aspergillosis (CPA), a type of infection. It typically presents radiological findings on a thorax CT scan as a spherical, shadow-shaped mass surrounded by air, also known as a fungus ball, due to the colonization of Aspergillus fungi within a preexisting cavity or cystic lesion in the lungs. ⁴ In the present case, there were no findings suggestive of aspergilloma such as the crescent sign on the CT scan, and the CT image of the mass resembled a metastatic mass.

Forms such as chronic cavitary pulmonary aspergillosis and chronic fibrosis pulmonary aspergillosis, including aspergilloma, are most often observed in people with a history of pulmonary tuberculosis, chronic obstructive pulmonary disease, pneumonia, bronchogenic cyst, lung abscess, allergic bronchopulmonary aspergillosis, lung cancer, lung operations, pneumothorax, and mostly in the lungs.^4,5

Lung aspergilloma has been reported rarely in two cases of malignant melanoma and head and neck cancer, apart from lung cancer.^5,6 Aspergilloma has also been reported as an extrapulmonary case in a rheumatology patient using immunosuppressive drugs. ⁷ In the current English literature review, to date, no case of pulmonary aspergilloma accompanied by pulmonary venous embolism has been reported in a patient who has undergone surgery for gastric cancer. In this case, we detected both a solitary nodular mass in the lung and pulmonary venous embolism findings on radiological imaging. Enoxaparin subcutaneously was started for the treatment of pulmonary embolism. The patient’s dyspnea improved with enoxaparin treatment for at least 3 months. No hemoptysis was observed in the patient during the diagnosis and anticoagulant treatment.

In cases of nodular aspergilloma of the lung, antifungal therapy is not effective and good results have been reported mostly with lobectomy and, to a lesser extent, with wedge resections. In addition, the incidence of fungal infections of the Aspergillus genus has been reported to decrease in operated Aspergillus cases. ⁵ In our case, the blood galactomannan test was negative. There was no evidence of tuberculosis or fungal growth in the sputum culture. No additional antifungal treatment was recommended by the infectious diseases specialist after surgery (Supplemental Material).

Because benign solitary nodules in the lung may mimic lung metastasis or primary lung cancer, ⁸ such patients should be particularly evaluated for metastasis in patients with primary lung cancer or a history of cancer. Our case had undergone surgery due to gastric cancer in March 2017, and the disease was still in remission. In our patient, ¹⁸FDG PET/CT imaging revealed a 16 × 14 mm nodular mass with high uptake (SUV max: 12.5) in the apical zone of the right upper lobe. The patient’s clinical condition improved with anticoagulant therapy. Due to the risk of pneumothorax associated with CT-guided biopsy, it was decided to remove the lung nodule via wedge resection. The patient underwent wedge resection of the mass, which was thought to be a solitary metastasis or primary lung cancer. The pathology evaluation was consistent with an aspergilloma, and no malignant cells were detected.

There are markedly improved outcomes with surgical resection of solitary lung metastases in patients with gastric cancer. Kanai et al. reported a median survival time of 19.7 months (range 10.2–63.7 months) with surgical resection of solitary lung metastases from patients with gastric cancer. ³ Yoshida et al. reported a 4-year survival rate of 75% with surgical resection of lung metastasis from gastric cancer. ⁹ These two studies demonstrated the survival benefit of surgical resection of solitary lung metastases. However, in gastric cancer patients with extrapulmonary organ metastases, lung metastases cause poor prognosis and the median 1- and 3-year survival rates in these patients were reported as 15.3% and 3.92%, respectively. ¹⁰ In patients with solid tumor cancer who are being followed up in remission, when solitary lung nodular masses are detected, like in the current case, confirmation by biopsy should be performed. However, in such patients who are not suitable for biopsy, surgical resection can be considered as an option for both diagnostic and therapeutic purposes.

Conclusion

In confirming lung metastases from solid organ tumors, if CT guidance or endobronchial biopsy is not possible, surgery can be an option for both diagnosis and treatment. Here, we present a case of a lung aspergilloma mimicking lung metastasis from gastric cancer in a patient with gastric cancer in remission.

Supplemental Material

sj-jpeg-1-sco-10.1177_2050313X261454857 – Supplemental material for A case of lung nodular aspergilloma mimicking tumor metastasis accompanied by pulmonary embolism in a gastric cancer patient in remission

Supplemental material, sj-jpeg-1-sco-10.1177_2050313X261454857 for A case of lung nodular aspergilloma mimicking tumor metastasis accompanied by pulmonary embolism in a gastric cancer patient in remission by Ali Osman Kaya, Aysun Kaya and Cemal Gundogdu in SAGE Open Medical Case Reports