A 74-year-old male presented with a right upper nodule on chest X-ray. He was admitted to our hospital for the purposes of close examination and treatment. Chest computed tomography (CT) revealed a nodular shadow in the upper right lobe. Smoking history was 1 pack/day × 55 years.
Clinical characteristics: Height: 169.7 cm, weight: 72.4 kg, body temperature: 36.1 °C, pulse rate: 88 beats/min, blood pressure: 120/66 mmHg, SpO2: 98%, elastic soft and well-moving lymphadenopathy of 7 × 5 cm in the left neck. No other special notes.
Laboratory data (Table 1):
Red blood cell count showed mild anemia. CRP, LDH, ALP, NSE, and soluble interleukin-2 receptor (sIL-2R) were elevated.
Imaging findings:
Chest X-ray (Fig. 1A): A nodular shadow of approximately 2 cm maximum diameter was found in the upper right lung field.
Chest CT (Fig. 1B): A 24 × 21 × 18 mm nodule with a cavity was found in Segment 1 of the upper right lobe.
Fluorodeoxyglucose-positron emission tomography (FDG-PET) (Fig. 1C): A maximum standardized uptake value (SUV) accumulation of 9.4 was observed in the nodule of the right upper lobe. In addition to strong accumulation in the left cervical lymph nodes, accumulation also occurred in both axillary lesions, near the pancreatic head, in both external iliac arteries, and in the right inguinal lymph nodes.
Clinical Course:
Bronchoscopy was performed to assess the lung lesions, and squamous cell carcinoma of the lung was diagnosed. Malignant lymphoma was diagnosed from a left cervical lymph node biopsy. At this point, the clinical stage of the lung cancer was stage IA, and the stage of malignant lymphoma was stage IVA, and thus, treatment for malignant lymphoma was given priority. After two courses of R-CHOP (Rituximab + cyclophosphamide + hydroxydaunorubicin + vincristine + prednisolone) therapy for malignant lymphoma, sIL-2R normalized to 466 from 14003 U/ml. However, chest radiographs and chest CT revealed nodular shadows in the right upper lung field that had increased, and new cavities appeared. On FDG-PET, maximum SUV in the lung tumor increased from 9.4 to 10.5, but accumulation in the lymphoma lesions remained only in the left inguinal region, with little accumulation in other areas. Surgery was then performed for the lung cancer. Another reason for the surgery for the lung cancer was discontinuation of chemotherapy due to relapse of hepatitis B. In April 2013, a right upper lobectomy and mediastinal lymph node dissection was performed for his lung cancer. The lesion was a white lobulated mass approximately 33 mm in size with cavitation.
Pathological findings (Figs. 2A, B, C):
Poorly differentiated squamous cell carcinoma of the lung and malignant lymphoma-like lesions were observed in the same foci (Fig. 2A). Immunohistochemical staining revealed that CD79a (Fig. 2B right), a B-cell marker, was positive, indicating diffuse large B-cell lymphoma. In addition, the area where AE1AE3 (Fig. 2C right), which is an epithelial marker, was positive and the area where CD79a was positive overlapped, suggesting that squamous cell carcinoma and malignant lymphoma were both present in the same lesion (Fig. 2B, 2C right). After the operation, eight courses of R-CHOP therapy were performed. However, the malignant lymphoma worsened, and 2nd - and 3rd -line treatments were attempted. However, the disease was not controlled, and he died 10 months after the operation.