| Abstract|| |
Aim: Although one-fourth of the pituitary tumors are inactive and silent, increased total volume of the pituitary gland exerts pressure on sella turcica and corrodes the clinoid processes, resulting in several problems. Therefore, determination of the prevalence of the concealed pituitary tumors is of major concern among clinical practitioners. This study was performed to determine the prevalence of these tumors in cadavers referred to the Iranian Legal Medicine Organization (Kahrizak, Tehran). Materials and Methods: This cross-sectional descriptive study was performed between June 2007 and February 2008. A total of 485 cadavers were selected by simple random sampling method. Pituitary glands were removed and then horizontally cut and four slides were prepared from each of them, stained by hematoxylin and eosin, and evaluated by a light microscope. For statistical analysis, SPSS software (version 16), Mann-Whitney U test, Kolmogorov-Smirnov nonparametric test (K-S test), and Chi-square test were used. Results: Of the 485 investigated cadavers, 365 (75.3%) were males with an average age of 42 ± 20.5 years and 120 (24.7%) were females with an average age of 44 ± 22 years. A total of 61 (12.6%) had concealed pituitary masses. No statistically significant difference was found between the mean age, sex, and body mass index (BMI) of the cadavers with and without concealed tumors (P=0.380 P=0.450, and P=0.884, respectively). Conclusions: In the present study, the prevalence of the concealed pituitary adenomas was 12.6%. There was no correlation between age, sex, and BMI and the prevalence of the concealed masses.
Keywords: Autopsy, concealed tumors, pituitary gland, prevalence, Iranian cadavers
|How to cite this article:|
Aghakhani K, Kadivar M, Kazemi-Esfeh S, Zamani N, Moradi M, Sanaei-Zadeh H. Prevalence of pituitary incidentaloma in the Iranian cadavers. Indian J Pathol Microbiol 2011;54:692-4
|How to cite this URL:|
Aghakhani K, Kadivar M, Kazemi-Esfeh S, Zamani N, Moradi M, Sanaei-Zadeh H. Prevalence of pituitary incidentaloma in the Iranian cadavers. Indian J Pathol Microbiol [serial online] 2011 [cited 2019 Apr 26];54:692-4. Available from: http://www.ijpmonline.org/text.asp?2011/54/4/692/91493
| Introduction|| |
Sellar and para-sellar masses present with clinical and radiological features ranging from asymptomatic incidental presentations/hormonal effects to compressive local mass effects. One-fourth of these tumors are endocrinologically inactive and silent. In the active ones, hyperprolactinemia or hypogonadism are the most common signs.  Several pathological lesions have been detected in the pituitary gland; adenoma is the most common among them that almost specifically arises in the anterior lobe of the gland. ,, In addition, epithelial neoplasms are the most common neoplasms in the pituitary gland with their origin from adenohypophysis cells which constitute about 15-20% of the neoplasms inside the skull. ,, However, pituitary tumors lead to dilatation of the sella turcica and corrosion of the clinoid edges and damage the chiasm or optic nerve resulting in reduced vision. ,,, Determining the prevalence of pituitary tumors in the general population is of major concern among the clinical specialists. ,,, Davis and his colleagues  showed that pituitary tumors were less prevalent compared to tumors in other parts of the body including tumors of the lungs, breasts, and colon. However, a meta-analysis on radiologic studies and autopsies, performed by Ezzat and his colleagues,  showed that one of each six persons is suffering from the pituitary tumors. Due to the controversial results in the literature and lack of accurate estimation of the prevalence of the concealed tumors of the pituitary gland in our country, this study was performed to determine the prevalence of these tumors in cadavers.
| Materials and Methods|| |
This cross-sectional descriptive study was performed between June 2007 and February 2008 in the Iranian Legal Medicine Organization (Kahrizak, Tehran), and 485 cadavers were selected by simple random sampling method. After opening the skull and removing the brain and cerebellum, pituitary gland was removed and put into 10% formalin solution. Samples were horizontally cut to prepare four slides form each sample, stained by hematoxylin and eosin (H and E) and evaluated by a light microscope. We did not perform the reticulin stain and immunohistochemistry and the diagnosis was based on the conventional H and E stain. Specifications of the cadavers including age, gender, body mass index (BMI), and pathologic changes such as presence or absence of concealed tumors were recorded in the above-mentioned checklist.
For analyzing the data, SPSS software (version 16), Mann-Whitney U test, Kolmogorov-Smirnov nonparametric test (K-S test), and Chi-square test were used and a P value less than 0.05 was considered to be statistically significant.
Information of the cadavers, such as the identity specifications, were kept completely secured and only codes were used for the review and analysis of the data. Our study was approved by the regional ethics committee.
| Results|| |
Of the 485 investigated cadavers, 365 (75.3%) were males with the average age of 42 ± 20.5 years and 120 (24.7%) were females with the average age of 44 ± 22 years. After calculating the cadavers' body mass index (BMI; BMI of 20-25 indicates optimal weight), they were divided into three groups: underweight (BMI < 20), normal range (20 < BMI < 25), and overweight (BMI > 25) groups. A total of 194 (40%), 187 (38.5%), and 104 (21.5%) cadavers were in underweight, normal range, and overweight groups, respectively. Of the 485 pathologic samples, 424 (87.4%) had no evidence (group I), while 61 (12.6%) had concealed pituitary masses (adenoma) (group II) [Figure 1]. No significant statistical difference was detected between the mean age of these two groups (P=0.380). Also, there were no significant statistical differences between three BMI groups regarding the prevalence of pituitary masses (P=0.884). Furthermore, the prevalence of the adenoma was not different between male and female cadavers (P=0.450).
|Figure 1: Concealed pituitary adenoma in a 65-year-old female (a and b) and a 72-year-old male (c and d), stained by hematoxylin and eosin (H and E; ×40 in a and c; ×10 in b and d)|
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| Discussion|| |
Pituitary adenomas diagnosed by methods such as computed tomography (CT) scan and magnetic resonance imaging (MRI) have a frequency of about 3.7-37%; while in studies performed on cadavers, it is about 1.4-27%. ,,,, Different statistical results are due to the different methods of histology sampling. , Number and thickness of the samples may affect the prevalence of malignancy; however, this subject has not yet been proven. ,, In this study, diagnosis of adenoma was made based on the proliferation of the endocrine cells with diffused, sinusoidal, or papillary growth pattern, loss of normal structure of acinar and stromal cells, and compression of the parenchymal tissues adjacent to the pituitary gland [Figure 1]. Additionally, the prevalence of the concealed pituitary adenomas was 12.6% which is less than the results obtained by the previous studies and may be justified based on the method of detection of the adenomas. Unlike other studies showing a relation between age and prevalence of the concealed pituitary masses, the present study showed no correlation between these two variables. ,, In addition, in this study, no association was detected between the gender of the cadavers and prevalence of the concealed masses, which is in accordance with the previous studies. ,,,,
However, in studies performed using diagnostic radiologic procedures and surgery, the prevalence of the concealed pituitary masses was more in women.  On the basis of the results obtained in this study, there was no statistically significant correlation between BMI and the prevalence of the concealed pituitary tumors. Other studies are warranted to survey the type of adenoma, such as functional and non-functional adenomas, and its subtypes, which could not be evaluated in this survey.
| Acknowledgment|| |
This study was supported by a grant from the Iranian Legal Medicine Organization.
| References|| |
|1.||Famini P, Maya MM, Melmed S. Pituitary Magnetic Resonance Imaging for Sellar and Parasellar Masses: Ten-Year Experience in 2598 Patients. J Clin Endocrinol Metab 2011;96:1633-41. |
|2.||Krikorian A, Aron D. Evaluation and management of pituitary incidentalomas- revisiting an acquaintance. Nat Clin Pract Endocrinol Metab 2006;2:138-45. |
|3.||Aron DC, Howlett TA. Pituitary incidentalomas. Endocrinol Metab Clin North Am 2000;29:205-21. |
|4.||Sanno N, Oyama K, Tahara S, Teramoto A, Kato Y. A survey of pituitary incidentaloma in Japan. Eur J Endocrinol 2003;149:123-7. |
|5.||Rosai J. Ackerman's Surgical Pathology. 8 th ed. New York: Mosby; 1996. |
|6.||Silverberg SG. Principles and practice of surgical pathology and cytopathology. 3 rd ed. New York: Churchill livingstone; 1997. |
|7.||Fletcher CD. Diagnostic histopathology of tumors. 2 nd ed. London: Churchill Livingstone; 2000. |
|8.||Tsang RW, Brierley JD. Radiation therapy for pituitary adenoma: Treatment outcome and prognostic factors. Int J Radiat Oncol Biol Phys 1994;30:557-65. |
|9.||Zierhut D, Flentje M, Adolph J, Erdmann J, Raue F, Wannenmacher M. External radiation therapy of pituitary adenoma. Int J Radiation Oncol Biol Phys 1995;33:307-14. |
|10.||Kovalic JJ, Grigsby PW, Fineberg BB. Recurrent pituitary adenoma after surgical resection. Radiology 1990;177:273-5. |
|11.||DeVita VT, Hellman S, Rosenberg SA. Cancer: Principles and Practices of Oncology. 6 th ed. Philadelphia, PA: Lippincott Williams and Wilkins; 2001. |
|12.||Nammour GM, Ybarra J, Naheedy MH, Romeo JH, Aron DC. Incidental pituitary macroadenoma: A population-based study. Am J Med Sci 1997;314:287-91. |
|13.||Asa SL. Tumors of the pituitary gland. In: Rosai J. Atlas of tumor pathology, 3 rd series Fascicle 22. Washington DC: Armed Forces Institute of Pathology; 1998. |
|14.||Muhr C, Bergstrom K, Grimelius L, Larsson SG. A parallel study of the roentgen anatomy of the sella turcica and the histopathology of the pituitary gland in 205 autopsy specimens. Neuroradiology 1981;21:55-65. |
|15.||Teramoto A, Hirakawa K, Sanno N, Osamura Y. Incidental pituitary lesions in 1,000 unselected autopsy specimens. Radiology 1994;193:161-4. |
|16.||Davis FG, Kupelian V, Freels S, McCarthy B, Surawicz T. Prevalence estimates for primary brain tumors in the United States by behavior and major histology groups. Neuro Oncol 2001;3:152-8. |
|17.||Ezzat S, Asa SL, Couldwell WT, Barr CE, Dodge WE, Vance ML, et al. The prevalence of pituitary adenomas: A systematic review. Cancer 2004;101:613-9. |
|18.||Aron DC, Howlett TA. Pituitary incidentalomas. Endocrinol Metab Clin North Am 2000;29:205-21. |
|19.||Camaris C, Balleine R, Little D. Microadenomas of the human pituitary. Pathology 1995;27:8-11. |
|20.||Parent AD, Brown B, Smith EE. Incidental pituitary adenomas: A retrospective study. Surgery 1982;92:880-3. |
|21.||Burrow GN, Wortzman G, Rewcastle NB, Holgate RC, Kovacs K. Microadenomas of the pituitary and abnormal sellar tomograms in an unselected autopsy series. N Engl J Med 1981;304:156-8. |
|22.||Fainstein Day P, Guitelman M, Artese R, Fiszledjer L, Chervin A, Vitale NM, et al. Retrospective multicentric study of pituitary incidentalomas. Pituitary 2004;7:145-8. |
|23.||Gorczyca W, Hardy J. Microadenomas of the human pituitary and their vascularization. Neurosurgery 1988;22:1-6. |
|24.||Parent AD, Bebin J, Smith RR. Incidental pituitary adenomas. J Neurosurg 1981;54:228-31. |
|25.||Ghorbani M, Kosari F, Mardani F, Saeednejad R, Mohammadi N, Akhlaghi M. Prevalence and distribution study of sella turcica tumors in 20 years and more old cadavers dissected in the legal medicine center of Tehran in 1383-1384. [Article in Persian] Sci J Forensic Med 2006;12:87-9. |
|26.||Kastelan D, Korsic M. High prevalence rate of pituitary incidentaloma: Is it associated with the age-related decline of the sex hormones levels? Med Hypotheses 2007;69:307-9. |
|27.||Char G, Persaud V. Asymptomatic microadenomas of the pituitary gland in an unselected autopsy series. West Indian Med J 1986;35:275-9. |
|28.||Tomita T, Gates E. Pituitary adenomas and granular cell tumors. Incidence, cell type, and location of tumor in 100 pituitary glands at autopsy. Am J Clin Pathol 1999;111:817-25. |
Department of Forensic Medicine and Toxicology, Tehran University of Medical Sciences, Hazrat Rasoul Akram Hospital, Niayesh Street, Sattar-Khan Ave., 1445613131, Tehran
Source of Support: None, Conflict of Interest: None