Thymus and lung mucosa-associated lymphoid tissue lymphoma with adenocarcinoma of the lung: a case report and literature review

BACKGROUND

Mucosa-associated lymphoid tissue (MALT) lymphoma is a common, low-grade, malignant B-cell lymphoma. However, simultaneous MALT lymphoma in the thymus and lung is extremely rare, and concomitant adenocarcinoma of the lung is even rarer. Herein, we report a rare case of a collision tumor in which MALT lymphoma was found in both the thymus and lung with Sjögren's syndrome (SS) and adenocarcinoma in the lung.

CASE PRESENTATION

A physical examination of a 32-year-old woman revealed an anterior superior mediastinal space-occupying lesion, and chest computed tomography (CT) indicated a nodular ground-glass opacity and irregular mixed-density focus in the right lung. All lung cancer-related tumor biomarkers were within normal ranges. The thymus and part of the lung tissue were surgically resected. The histopathology and molecular examinations confirmed MALT lymphoma of the thymus and lung with lung adenocarcinoma. SS was also diagnosed. No special postoperative treatment was performed for the MALT lymphoma, and the patient underwent immunosuppressive therapy for SS after 4 months of follow-up observation.

CONCLUSIONS

MALT lymphoma of the thymus and lung tissues has no specific presentation on imaging and is difficult to differentiate from common malignant tumors, and the definite diagnoses of these tumors are highly dependent on histopathological examination in combination with molecular testing and cytogenetics. SS may be an important potential condition for the occurrence of MALT lymphoma in the thymus and lung. Additional similar cases are needed to clarify the biological pathways and potential molecular mechanisms of rare lymphomas and collision tumors.

Synchronous primary pulmonary adenocarcinoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue: A case report and literature review

RATIONALE

Synchronous pulmonary lymphoma and carcinoma is relatively rare. And synchronous pulmonary lymphoma and adenocarcinoma in the same site is extremely rare.

PATIENT CONCERNS

We presented a 69-year-old female with a tumor mass in right upper lung.

DIAGNOSIS

Pathological and immunohistochemical findings revealed lung adenocarcinoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue.

INTERVENTIONS

The patient received thoracoscopic guided right upper lobectomy and focal lymph node dissection after systemic anesthesia. Besides, 6 cycles of chemotherapy were given based on meprednisone, gemcitabine and cisplatin in local hospital.

OUTCOMES

In the 12-month follow-up, the patient was still alive with no local recurrence, metastasis and lymph node involvement.

LESSON

A comprehensive literature research was performed, and 6 cases of synchronous pulmonary lymphoma and adenocarcinoma in the same site and 10 cases in different sites were identified since 2000. Most patients with synchronous pulmonary lymphoma and carcinoma were middle-aged and elderly with the median age was 64 years presenting a male predisposition. The most frequent type of primary pulmonary lymphoma was B-cell non Hodgkin lymphoma, especially mucosa-associated lymphoid tissue lymphoma, and the lung cancer is predominantly adenocarcinoma.