A huge solitary fibrous tumor of the pleura with hypoglycemia and abnormalities of endocrine in the anterior lobe of the pituitary gland
Article Outline
Summary
We report on a 34-year-old female who presented with left huge solitary fibrous tumor of the pleura (SFTP) occupying the left pleural cavity, complicated with severe hypoglycemia and various endocrine abnormalities. The serum levels of PRL and LH on admission were high and brain MRI showed enlargement of the pituitary gland. After resection of SFTP, the hypoglycemia, various endocrine abnormalities and size of the pituitary gland normalized. There have been no previous reports on SFTP complicated with not only hypoglycemia but also abnormal serum levels of PRL and LH and enlargement of the pituitary gland.
Keywords: Solitary fibrous tumor of the pleura, Hypoglycemia, Hyperplasia of the pituitary gland, LH, FSH
Introduction
Solitary fibrous tumor of the pleura (SFTP) associated with severe hypoglycemia is rare. There have been no reports of SFTP complicated with not only hypoglycemia but also serum prolactin (PRL) and luteinizing hormone (LH) abnormalities and hyperplasia of the pituitary gland. We report on a 34-year-old female who presented with a huge left SFTP occupying the left pleural cavity on chest CT scan complicated with severe hypoglycemia and various endocrine abnormalities.
Case report
A 34-year-old woman was referred for a lesion occupying the left pleural space on chest X-ray (Figure 1) and severe hypoglycemic coma. On admission, serum glucose level was 40
mg/dl, and levels of insulin were not detectable. There were no respiratory symptoms such as cough, dyspnea, or chest pain. Hypoglycemia was treated with continuous 5% glucose infusions with good control of the crisis. The serum levels of PRL and LH on admission were high: PRL 36.9ng/ml (normal range: 4.9–29.3ng/ml), and LH 15.0mlU/ml (normal range: 2.4–12.6mlU/ml). The serum levels of TSH, ACTH, FSH, and GH produced in the anterior lobe of the pituitary gland were within the normal ranges. Brain MRI showed hyperplasia of the pituitary gland. Chest CT scan showed a huge mass occupying the left pleural cavity.
Figure 1.
Chest roentgenogram showing the lesion occupying the left pleural space.
Fine needle aspiration biopsy (FNAB) was performed, and a diagnosis of SFTP was made.
She underwent resection of the tumor by a left posterolateral thoracotomy, which revealed a gigantic lobulated mass, separate from the usual left intrathoracic structures. There were two main vascular pedicles, one arising from the oblique fissure and the other from the pleural surface of the left hemidiaphragm. There were several other minor vascular pedicles arising from the parietal pleura.
The macroscopic appearance of the cut surface of the resected tumor showed a smooth, yellowish white, firm, and irregularly lobulated mass with white fibrous band. The resected mass weighed 3950g.
Microscopic examination revealed interlacing fascicles of spindle tumor cells interspersed with thick bundles of collagen in a solid portion (Figure 2a). There was no high cellularity with crowding and overlapping of nuclei, cellular pleomorphism, and no high mitotic count.
Figure 2.
(a) Microscopic specimen of the tumor revealed interlacing fascicles of spindle tumor cells interspersed with thick bundles of collagen in a solid portion (H&E ×100). (b) Microscopic specimen of the tumor with positivity for immunohistochemical staining with CD34 (×250).
Immunohistochemically, most of the tumor cells stained positive for CD34 (Figure 2b), vimentin, and bcl-2, but negative for α-SMA, c-kit, desmin, S-100, and AE1/AE3. The ki-67 labeling index was under 1%. The tumor was diagnosed as a benign SFTP. The serum glucose level in the patient returned to normal immediately after resection of the tumor, and the serum levels of PRL and LH returned to normal 3 months after resection. Brain MRI showed that the enlarged pituitary gland had returned to a normal size.
She has been followed up in our outpatient clinic for 16 months without further disease manifestations.
Discussion
SFTP is rare neoplasm that accounts for 8% of benign pathologic diseases of the chest and 10% of pleural neoplasms. Its incidence is 2.8 per 100,000 registered hospital patients. Malignant forms account for approximately 12% of all fibrous tumors of the pleura. They are rarely pedunculated and may arise from the visceral or parietal pleura.2
SFTP can present with various symptoms such as intrathoracic symptoms (dyspnea, chest pain, hemoptysis), systemic symptoms (hypoglycemia, hypertrophic osteoaethropathy), or nonspecific symptoms (fever, weight loss, fatigue).1 As a systemic symptom, non-islet cell tumor hypoglycemia (NICTH) is a paraneoplastic syndrome occurring in patients with large slow-growing tumors such as SFTP, hepatomas, sarcomas, and other tumors arising from the mesenchymal tissue.3 Megyesi et al.2 reported five patients with hypoglycemia associated with non-islet cell tumors who had increased serum levels of non-suppressive insulin-like activity. Insulin-like growth factor (IGF)-2 may be produced directly from the tumor or as a larger precursor by the neoplasm. When IGF-2 serum level was high, insulin secretion was suppressed: both were reported to have returned to normal after exeresis of the neoplasm.4 We did not assess preoperative IGF-2 serum level in this case, but NICTH was controlled by resection of the tumor. In this case, the serum levels of PRL and LH in the patient returned to normal 3 months after resection of the tumor, and brain MRI showed that the enlarged pituitary gland returned to a normal size. SFTP complicated with enlargement of the pituitary gland and high serum levels of PRL and LH produced in the anterior lobe of the pituitary gland has not been reported before. The relation between the production of IGF-2, the secretion of PRL and LH, and enlargement of the pituitary gland has not been reported before, but the serum levels of PRL and LH in the patient returned to normal and the size of the pituitary normalized after resection of the tumor.
The treatment of choice for benign SFTP is complete surgical resection. However, for malignant SFTP cases, there is no established systemic therapy, either preoperatively or postoperatively, despite the fact that malignant SFTP has shown distant metastasis.6 Recurrence after complete surgical resection is possible in benign and malignant variants, therefore, chest roentgenogram is the most important diagnostic examination for the tumor, and chest CT scan may also show low density and heterogeneous areas in large neoplasms due to necrosis, mixoid degeneration or hemorrhage.5
Long-term annual follow-up with chest roentgenogram and CT scan is highly recommended.
Conflict of interest statement
None of the authors have a conflict of interest to declare in relation to this work. Examples of conflicts of interest to declare in relation to this work include employment, consultancies, stock ownership, honoraria, paid expert testimony, patent applications/registrations, and grants or other funding.
References
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- . Three types of spindle cell tumors of the pleura: fibroma, sarcoma, and sarcomatoid mesothelioma. Am J Surg Pathol. 1988;12:747–753
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PII: S1755-0017(07)00004-8
doi:10.1016/j.rmedc.2007.10.001
© 2007 Elsevier Ltd. All rights reserved.
