263
Tüberküloz ve Toraks Dergisi 2011; 59(3): 263-265Giant mediastinal parathyroid adenoma
Hüseyin ÇAKMAK1, Arif Osman TOKAT2, Sezgin KARASU2, Murat ÖZKAN3
1SB Ankara Onkoloji Eğitim ve Araştırma Hastanesi, Göğüs Cerrahisi Kliniği, Ankara,
2 SB Ankara Eğitim ve Araştırma Hastanesi, Göğüs Cerrahisi Kliniği, Ankara,
3 Ankara Üniversitesi Tıp Fakültesi, İbn-i Sina Hastanesi, Göğüs Cerrahisi Anabilim Dalı, Ankara.
ÖZET
Dev mediastinal paratiroid adenoma
Paratiroid adenomlar ve paratiroid hiperplazisi primer hiperparatiroidizmin en sık görülen sebepleridir. Paratiroid adenom- lar seyrek olarak çok büyük boyutlara ulaşır. Burada mediasten yerleşimli kitle ve hiperkalsemi saptanan 63 yaşındaki ka- dın hasta sunulmaktadır. Olguda ektopik hipersekretuar paratiroid adenomuna bağlı yüksek intakt parathormon seviye- si saptandı (642 pg/mL). Kesin histolojik tanı paratiroid adenoma olarak rapor edildi. Olgudaki paratiroid adenomu 7 x 5 x 4 cm boyutları ve 145 g ağırlığı ile literatürdeki en büyük kitle idi. Kitle dev boyutlarına rağmen hiperkalsemi semptom- larına yol açmamıştı.
Anahtar Kelimeler: Mediasten, hiperkalsemi, paratiroid adenomu.
SUMMARY
Giant mediastinal parathyroid adenoma
Hüseyin ÇAKMAK1, Arif Osman TOKAT2, Sezgin KARASU2, Murat ÖZKAN3
1Clinic of Chest Surgery, Ankara Oncology Training and Research Hospital, Ankara, Turkey,
2 Clinic of Chest Surgery, Ankara Training and Research Hospital, Ankara, Turkey,
3 Department of Chest Surgery, Ibn-i Sina Hospital, Faculty of Medicine, Ankara University, Ankara, Turkey.
Primary hyperparathyroidism is most commonly caused by either a parathyroid adenoma or parathyroid hyperplasia. Pa- rathyroid adenomas also rarely attain huge proportions. We present a case of a 63-year-old female patient causing hyper- calcemia and the mass which is located in the mediastinum. High intact parathormone level secondary to an ectopic hyper- secretory parathyroid adenoma were detected (642 pg/mL). It was removed via a right thoracic approach. In this case pa- rathyroid adenoma measuring 7 x 5 x 4 cm and weighing 145 g; to our knowledge the greatest mass reported in the lite- rature. Despite its huge size it did not cause many of the hypercalcemic symptoms.
Key Words: Mediastinum, hypercalcemia, parathyroid adenoma.
Yazışma Adresi (Address for Correspondence):
Dr. Arif Osman TOKAT, SB Ankara Eğitim ve Araştırma Hastanesi, Göğüs Cerrahisi Kliniği, 06340 ANKARA - TURKEY
e-mail: aostokat@hotmail.com
Primary hyperparathyroidism is most commonly caused by either a parathyroid adenoma or parathyroid hyperp- lasia. Giant parathyroid adenomas are very rare (1). We present a case of severe hypercalcemia and very high intact parathormone level secondary to an ectopic hypersecretory huge parathyroid adenoma. Despite its huge size it did not cause many of the hypercalcemic symptoms usually associated with large adenomas.
CASE REPORT
A 63-year-old woman visited her physician because of 3-months history of headache and fatigue. She denied changes in her voice, dyspnea, dysphagia, or muscu- loskeletal pain. There was no relevant medical or fa- mily history. Physical examination was normal. Abnor- mal calcium and phosphate levels were detected in blood analysis and abnormal right upper mediastinal shadow on chest x-ray film was detected (Figure 1).
The patient was referred to the thoracic surgery depart- ment for further evaluation of mediastinal mass ca- using hypercalcemia. Her serum calcium and phosp- horus levels were 13.2 mg/dL and 2.5 mg/dL, respec- tively. Intact parathormone level was 642 pg/mL (nor- mal range 8 to 97 pg/dL). A technetium-99m pertech- netate methoxy-isobutyl-isonitrite (Tc-99 m MIBI) scan was revealed a mass in the mediastinum. Computed tomography (CT) revealed a heterogeneous hypoden- se right paratracheal mass compressing esophagus (Figure 2). A fine needle aspiration under CT guidance did not yield tumor cells. The thyroid gland appeared normal and no other pathologic lesion was found on USG and scintigraphy.
The right posterolateral thoracotomy was performed with a double-lumen endotracheal tube for single lung ventilation. The mass approximately 10 cm width was revealed at the posterior mediastinum. The vascular
pedicle of the mass originated in the mediastinum. It was freed from the surrounding tissue and excised. The specimen was measured 7 x 5 x 4 cm in dimensions and weighing 145 g. The thoracostomy tube was remo- ved on the first post-operative day, and there were no surgical complications. Postoperative serum calcium levels dramatically decreased to the levels of 6 mg/dL, and she was supported with oral calcium and vitamin D. The histopathological diagnosis confirmed the lesi- on as parathyroid adenoma. Intact parathormone level was 47 pg/mL on the postoperative day 12.
DISCUSSION
Parathyroid tumors are usually located on the posterior capsule of the thyroid but may be in other ectopic lo- cations (1). Parathyroid glands are known to be occur- ring in aberrant locations, mainly in the throid pa- renchyma and less commonly in the mediastinum (2).
An enlarged gland can descend into the mediastinum because of its increased weight as a result of intratho- racic negative pressure and esophageal movement (3).
The inferior parathyroids, derived from the 3rdbranchi- al pouch along with the thymus, have a more variable position. Less than two thirds are found close to the lo- wer pole of the thyroid but the remainder are usually fo- und within the thyrothymic ligament or in the medias- tinum (4).
Ectopic locations is indoubtedly related to the migra- tory pathways of embriologic parathyroid tissue to the adult positions. Within these migratory pathways of pa- rathyroid tissue, rare locations have been found as cep- halad as carotid artery bifurcations (undescended pa- rathyroid glands) and as caudal as pericardium (2).
The mediastinum is the most frequent location for ec- Giant mediastinal parathyroid adenoma
Tüberküloz ve Toraks Dergisi 2011; 59(3): 263-265
264
Figure 1. Chest X-ray and mediastinal mass of the patient.
Figure 2. Thorax computerized tomography of the patient showing a posterior mediastinal mass near the esophagus and trachea.
topic parathyroid tumors, with approximately 20% of parathyroid tumors located in the mediastinum (1).
70% of the ectopic parathyroid glands are located in the thymus. They can be removed through a cervical approach with or without a sternotomy. Rarely, the ec- topic glands located deep in the mediastinum require a thoracotomy for removal including that in the present case, can not be extracted through a cervical approach because the glands are located deep in the posterior mediastinum, aortopulmonary window, and pericardi- um (5,6).
It has been found that an increased glandular mass cor- relates with the severity of primary hyperparathyro- idism and the subsequent risk of transient postoperati- ve hypocalcemia (7). Because of the high secretory output, as measured by intact parathormone levels the major proportion of this enlarged gland was probably hypereractive because of its increased cellularity.
Giant parathyroid adenomas are very rare. The usual weight of a parathyroid adenoma ranges from 1 to 70 mg. Only there are sporadic reports of tumors were re- ported weighing more than 20 g (2). Giant parathyroid adenomas are extremely rare. There are sporadic re- ports of large adenomas attaining masses of 70 g (8).
The most frequent etiological association being that se- en with irradiation, for example, in survivors of the ato- mic bomb (9).
Power et al. were reported a giant parathyroid adeno- ma at 2005 which measuring 8 x 5 x 3.5 cm and weig- hing 110 g. They claimed that it was the greatest in the literature. In our case parathyroid adenoma measuring 7 x 5 x 4 cm and weighing 145 g is the greatest mass reported in the literature in our knowledge. Extremely high intact parathormone level was detected secondary to an ectopic hypersecretory huge parathyroid adeno-
ma. Despite its huge size and high intact parathormo- ne levels it did not cause of the hypercalcemic symp- toms which also makes this case noteworthy.
CONFLICT of INTEREST None declared.
REFERENCES
1. Fortson JK, Patel VG, Henderson VJ. Parathyroid cysts: a case report and review of the literature. Laryngoscope 2001; 111:
1726- 8.
2. Power C, Kavanagh D, Hill AD, O'Higgins N, McDermott E.
Unusual presentation of a giant parathyroid adenoma: report of a case. Surg Today 2005; 35: 235-7.
3. Knight R, Ratzer ER, Fenoglio ME, Moore JT. Thoracoscopic ex- cision of mediastinal parathyroid adenomas: a report of two cases and review of the literature. J Am Coll Surg 1997; 185:
481-5.
4. Butterworth PC, Nicholson ML. Surgical anatomy of the pa- rathyroid glands in secondary hyperparathyroidism. J R Coll Surg Edinb 1998; 43: 271-3.
5. Prinz RA, Lonchyna V, Carnaille B, Wurtz A, Proye C. Thora- coscopic excision of enlarged mediastinal parathyroid glands.
Surgery 1994; 116: 999-1005.
6. Wang C, Gaz RD, Moncure AC. Mediastinal parathyroid explo- ration: a clinical and pathological study of 47 cases. World J Surg 1986; 10: 687-95.
7. Zamboni WA, Folse R. Adenoma weight: a predictor of transi- ent hypocalcemia after parathyroidectomy. Am J Surg 1986;
152: 611-5.
8. Tsuchiya A, Endo S, Abe R. Giant adenoma of the parathyro- id: report of a case. Surg Today 1993; 23: 465-7.
9. Takeichi N, Nishida T, Fujikura T, Hiraoka T, Wakabayashi T, Yotsumoto I, et al. Two cases of large functioning parathyroid adenomas in atomic bomb survivors. Gan No Rinsho 1983;
29: 851-4.
Çakmak H, Tokat AO, Karasu S, Özkan M.
