Concurrence of granular cell tumor and Mycobacterium tuberculosis.

Abstract: Granular cell tumors (GCT) are rare, usually benign neoplasms of Schwann cell origin. Since discovery in 1926, fewer than 80 cases of GCT involving the lung have been reported. This report presents a 45-year-old male who presented with symptoms consistent with chronic pancreatitis associated with night sweats, weight loss, and a chronic productive cough. Chest radiography revealed a 3 X 4 cm left upper lobe lung mass with an unremarkable right lung field. Bronchoscopy revealed mixed mucosal abnormalities in the left upper lobe and a 4-mm polypoidal lesion in the right lower lobe. Bronchial washings stained positive for acid-fast bacilli. The left upper lobe lesion biopsy showed granulomatous inflammation with caseous necrosis consistent with tuberculosis. The right lower lobe lesion was a GCT without evidence of tuberculosis. This report reviews the literature regarding GCT and presents this unusual case of granular cell tumor co-occurring with active tuberculosis.

Key Words: granular cell tumor, Mycobacterium tuberculosis, concurrence

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We report a case of rare granular cell tumor (GCT) of the lung that occurred incidentally with infection by Mycobacterium tuberculosis. Although pulmonary GCTs have been found in association with sarcoid and HIV infection, to date, no known reported case has occurred with tuberculosis.

Case Report

Our patient is a 45-year-old black male with a history of heavy alcohol use who presented with symptoms of chronic pancreatitis. Review of systems was remarkable for a 4-month history of cough productive of yellow-green sputum, night sweats, anorexia, and a 10-pound weight loss. He denied hemoptysis or other pulmonary symptoms. Physical examination was remarkable only for a low-grade fever of 100.4[degrees] and mild epigastric tenderness.

Laboratory data revealed an elevated lipase at 417 mg/dL and white blood cell count of 18.5 [mm.sup.3], with 77% neutrophils, 8.3% monocytes, and 13.1% lymphocytes. Chest radiography showed a 3 X 4 cm left upper lobe mass. Chest CT scan revealed the same 4-cm mass surrounding the left upper lobe bronchus and a 2-cm lymph node in the anterior mediastinum. Ultrasound of the abdomen done for workup of his abdominal complaints revealed only calcifications in the tail of the pancreas.

Bronchoscopy revealed a mucosal abnormality with concentric narrowing in the anterior segment of the left-upper lobe. In addition, the right lower lobe anterior basal segment was noted to have a multilobulated mucosal lesion.

Biopsy of the left upper lobe lesion revealed only granulomatous inflammation, whereas a portion of granular cell tumor was noted on the biopsy of the right lower lobe lesion. No mitosis or cellular atypia was identified. (Figure).

Endobronchial washings from the left upper lobe showed acid-fast organisms; therefore pyrazinamide, ethambutol, rifampin, and isonicotinic acid hydrazide were given. Cultures ultimately grew M tuberculosis. Ten days after antituberculin therapy was initiated, the patient was without fever, cough, or night sweats, and his appetite had significantly improved. The abdominal complaints resolved.

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Discussion

Granular cell tumors were first described by Abrikossoff in 1926. (1) They typically present on the tongue, skin, or breast. The first case of granular cell tumor of the lung was described in 1939. (2) Since then, approximately 80 cases have been reported. (3) Although the histogenesis of GCT is unknown, immunohistochemical stains (positive for S-100 protein, neuron-specific enolase, NK1-C3, and so forth) and ultrastructural findings (eg, myelin residues, long-spacing collagen, arrays of neuritic processes among tumor cells) indicate neural (Schwann cell) derivation of GCT. It typically presents in the fourth or fifth decades of life and more commonly affects patients of African-American descent.

Most patients with pulmonary GCT present secondary to local complications such as obstruction, hemoptysis, or weight loss. Although our patient did present with cough and weight loss, we attribute these symptoms to tuberculosis in view of the fact that his symptoms abated with antituberculin medications.

Pulmonary GCTs tend to behave in a benign fashion. Although malignant GCTs have been reported in the literature, no case of primary malignant granular cell tumor of the lung has been described. (5-8) Few cases have been reported in which pulmonary GCT was found in association with sarcoid and HIV disease, but to our knowledge, no other cases of concurrence between GCT and tuberculosis have been reported. Since both lesions were located in different lobes and because the biopsied specimen from the right lower lobe showed GCT without evidence of tuberculosis, it is most likely that these lesions represent two separate entities. It is still unknown whether there is any association between pulmonary GCTs and an increased susceptibility to infection with tuberculosis, making this an unusual case.

Treatment options for granular cell tumors of the lung include surgical excision, bronchoscopic removal, or treatment with a laser. (9) We chose to follow our patient with serial chest radiographs and close monitoring of pulmonary symptoms. He is currently asymptomatic.

Conclusion

Granular cell tumors are rare, usually benign neoplasms of Schwann cell origin that most frequently occur in the tongue, skin, or breast. Although granular cell tumors have been found in association with sarcoidosis and HIV infection, to date no known reported case has occurred with tuberculosis. These probably represent two separate entities, but whether a relation exists between pulmonary GCT and susceptibility to infection with tuberculosis is unclear and should be studied further.

References

1. Abrikossoff A. Uber myohne Ausgehended von der gestreiften willkurlichen muskulatur. Virchows Arch Pathol Anat 1926;260:215-233.

2. Kramer R. Myoblastoma of the bronchus. Ann Otol Rhinol Laryngol 1939;48:1083-1086.

3. Yang KL, and Ortiz L. Granular cell myoblastoma involving multiple organs. South Med J 1993;86:448-449.

4. Deavers M, Guinee D, Koss M, and Travis W. Granular cell tumors of the lung: Clinicopathologic study of 20 cases. Am J Surg Pathol 1995;19:627-635.

5. Parayno P, and August C. Malignant granular cell tumor: Report of a case with DNA ploidy analysis. Arch Pathol Lab Med 1996;120:296-300.

6. D'Andrea, et al. Granular cell myoblastoma (Abrikossoff tumor) of the chest wall: A never described site of a rare tumor. J Thorac Cardiovasc Surg 1994;108:792-793.

7. Jardines L, et al. Malignant granular cell tumors: Report of a case and review of the literature. Surgery 1994;116:49-54.

8. Simsir A, et al. Malignant granular cell tumor: A case report and review of the recent literature. Hum Pathol 1996;27:853-858.

9. Epstein L, and Mohsenifar Z. Use of Nd: YAG laser in endobronchial granular cell myoblastoma. Chest 1993;104:958-960.

Youngsook Yoon, MD, and Karen Curry, MD

From the Department of Medicine/Pulmonary and Critical Care Division, Medical University of Ohio, Toledo, Ohio.

Reprint requests to Youngsook Yoon, MD, Department of Medicine/Pulmonary and Critical Care Division, Medical University of Ohio, 3120 Glendale Avenue, Ruppert Health Center, Room 0012, Toledo, OH 43614-5809. E-mail: [e-mail]

Accepted May 9, 2005.

RELATED ARTICLE: Key Points

* Granular cell tumors are benign tumors.

* Histogenesis is unclear.

* Immunochemical stains and ultrastructural findings indicate neural derivation.

* An unusual case of granular cell tumor co-occurring with active tuberculosis is presented.