eISSN: 2084-9869
ISSN: 1233-9687
Polish Journal of Pathology
Current issue Archive Manuscripts accepted About the journal Supplements Editorial board Abstracting and indexing Subscription Contact Instructions for authors Ethical standards and procedures
SCImago Journal & Country Rank
2/2016
vol. 67
 
Share:
Share:
more
 
 

Blue nevus presenting as an endocervical polyp

Sayuri Masuko
,
Yoshihiro Ikura
,
Hiroki Kato
,
Yasuhiro Iwai

Pol J Pathol 2016; 67 (2): 191-194
Online publish date: 2016/08/02
Article file
- Quiz.pdf  [0.45 MB]
Get citation
ENW
EndNote
BIB
JabRef, Mendeley
RIS
Papers, Reference Manager, RefWorks, Zotero
AMA
APA
Chicago
Harvard
MLA
Vancouver
 
PlumX metrics:
 

Introduction

Blue nevi of the uterine cervix are benign melanocytic neoplasms, which were once considered to be rare and were usually found incidentally in hysterectomy specimens [1, 2, 3, 4, 5, 6, 7, 8].
We report herein a case of blue nevus of the uterine cervix presenting as an endocervical polyp. Histological findings were completely the same as previously reported, but immunohistochemical findings were in partial disagreement with those described in some previous publications [8, 9, 10]. We discuss possible reasons for this discordance.

Case report

A 58-year-old Japanese female who complained of body weight loss (–4.7 kg/year) was referred to our hospital. The patient had no medical history of abnormal genital tract bleeding but a gynecological examination was performed as a part of a systemic examination. In addition to multiple uterine myomas (up to 4 cm in diameter) detected by transvaginal ultrasonography, a small endocervical polyp (5 mm in length) was found and excised promptly. Although the macroscopic observation by the gynecologist revealed no remarkable findings, examination of the histological specimen showed many pigmented spindle-shaped cells distributed in the stromal portion of the polyp (Fig. 1). Histochemical special stains verified that the intracellular pigments were melanin granules (Fig. 2). Immunohistochemical analyses using red chromogen (Bond Polymer Refine Red Detection, Leica Biosystems, Nussloch, Germany) further revealed that the cells were positive for S100 protein, SOX10, HMB45, and MART-1 (Fig. 3). Based on the characteristic cellular morphology and immunohistochemical findings, the lesion was diagnosed as being a blue nevus, and malignant melanoma was denied. Despite detailed medical examinations, the cause of the body weight loss was not identified.

Discussion

Although reports of endocervical blue nevi have been few, recent comprehensive pathologic studies revealed that this type of melanocytic disease was not so rare, especially in Japan [11, 12]. Their biological nature is completely benign corresponding to cutaneous tumors [10, 13]. The origin of melanin-loaded tumor cells has been suggested to differ from that of cutaneous tumors [8, 11, 12]. However, the present immunohistochemical results, S100 protein (+), SOX10 (+), HMB45 (+), and MART-1 (+), indicated that tumor cells of our case possessed representative melanocytic characters [14].
Their distinctive morphology, spindle-shape or dendritic contours and dark brown cytoplasmic pigments serve as reliable diagnostic hallmarks [10, 13]. A careful differential diagnosis is necessary to distinguish blue nevi from their malignant counterpart, desmoplastic melanoma, which can develop as a primary uterine cervical tumor [15]. Immunohistochemically, whereas blue nevi are positive for most of the representative melanocytic markers including S100 protein, HMB45 and MART-1, desmoplastic melanomas are negative for the latter two markers [13].
We could diagnose the present lesion as a benign blue nevus through prudent interpretation of the histological, histochemical and immunohistochemical findings, which were in agreement with descriptions in a dermatopathology textbook and most previous pathologic case reports. Concerning immunohistochemical features, the tumor cells were described as being positive for S100 protein, HMB45 and MART-1 [2, 3, 4, 5, 6, 7, 13]. Surprisingly, however, the immunohistochemical features described in latest edition of a gynecopathology textbook were different from our findings and previous reports; that is, this textbook stated that endocervical blue nevi are usually negative for HMB45 and MART-1 [10]. Certainly, two reports described that endocervical blue nevi were negative for HMB45 [8, 9], but no report has stated MART-1 negative. We could not find the reason why the textbook explained that MART-1 was usually negative.
As for the discordance in the HMB45-immunostaining results, we considered two possibilities. One is the existence of tumor subtypes. HMB45 is a melanosome-related antigen. While premature melanosomes are intensely stained with the antibody, late-stage melanosomes are hardly stained [16]. As above, the cellular origin of endocervical blue nevi has been suggested to be different from cutaneous tumors [8, 11, 12], and there may be tumor subtypes depending on cellular maturation.
The other possibility is derived from differences in the immunohistochemical techniques used. Standard brown chromogen potentially induces misinterpretation of findings on melanin-loaded cells. A pre-stain bleach technique seems to provide a reasonable resolution, but may weaken immune reactivity [7]. An alternative red chromogen has a great advantage when the immunohistochemical staining targets melanin-loaded cells [17].
In conclusion, we experienced a case of blue nevus of the uterine cervix presenting as an endocervical polyp. Detailed histological and immunohistochemical examinations led to the correct pathologic diagnosis. Endocervical blue nevi, as well as cutaneous tumors, are usually positive for S100 protein, SOX10, HMB45 and MART-1 immunohistochemically.

Acknowledgments

The authors thank Mr. Takeshi Nakatani for his excellent technical support.

The authors declare no conflict of interest.

References

1. Hagiwara T, Kaku T, Kobayashi H, et al. Coexisting vulvar malignant melanoma and blue nevus of the cervix. Gynecol Oncol 2005; 99: 519-520.
2. Zevallos-Giampietri EA, Barrionuevo C. Common blue nevus of the uterine cervix: case report and review. Appl Immunohistochem Mol Morphol 2004; 12: 79-82.
3. Handa U, Mohan H, Garg S. Incidental detection of pigmented lesions in the cervix. Aust N Z J Obstet Gynaecol 2007; 47: 254-255.
4. Szumi³o J, Patel A, Patel S, et al. Blue nevus of the endocervix. Folia Morphol (Warsz) 2010; 69: 62-64.
5. Eskue K, Prieto VG, Malpica A. Cellular blue nevus of the uterus: a case report and review of the literature. Int J Gynecol Pathol 2010; 29: 583-586.
6. Parada D, Pe¼a KB, Riu F. Coexisting malignant melanoma and blue nevus of the uterine cervix: an unusual combination. Case Rep Pathol 2012; 2012: 986542.
7. Ishida M, Kagotani A, Yoshida K, et al. Endometrioid adenocarcinoma concurrent with a blue nevus of the endometrium and uterine cervix: A case report. Oncol Lett 2013; 6: 1219-1221.
8. Craddock KJ, Bandarchi B, Khalifa MA. Blue nevi of the Müllerian tract: case series and review of the literature. J Low Genit Tract Dis 2007; 11: 284-289.
9. Tran TA, Niu G, Tomasello CA, et al. The spectrum of grossly visible pigmented lesions in the uterine cervix: a prospective study. Int J Gynecol Pathol 2014; 33: 89-99.
10. Nucci MR, Carcangiu ML, Ferry JA, et al. Melanocytic tumours. In: Kurman RJ, et al. (eds.). WHO Classification of Tumours of Female Reproductive Organs, 4th ed. Lyon: International Agency for Research on Cancer 2014: 204.
11. Uehara T, Izumo T, Kishi K, et al. Stromal melanocytic foci (“blue nevus”) in step sections of the uterine cervix. Acta Pathol Jpn 1991; 41: 751-756.
12. Uehara T, Takayama S, Takemura T, et al. Foci of stromal melanocytes (so-called blue naevus) of the uterine cervix in Japanese women. Virchows Arch A Pathol Anat Histopathol 1991; 418: 327-331.
13. Elder DE, Elenitsas R, Murphy GF, et al. Blue nevi. In: Elder DE (ed.). Lever’s Histopathology of the Skin. 11th ed. Wolters Kluwer, Philadelphia 2015; 856-861.
14. Nonaka D, Chiriboga L, Rubin BP. Sox10: a pan-schwannian and melanocytic marker. Am J Surg Pathol 2008; 32: 1291-1298.
15. Ishikura H, Kojo T, Ichimura H, et al. Desmoplastic malignant melanoma of the uterine cervix: a rare primary malignancy in the uterus mimicking a sarcoma. Histopathology 1998; 33: 93-94.
16. Taatjes DJ, Arendash-Durand B, von Turkovich M, et al. HMB-45 antibody demonstrates melanosome specificity by immunoelectron microscopy. Arch Pathol Lab Med 1993; 117: 264-268.
17. Schaumburg-Lever G. The alkaline phosphatase anti-alkaline phosphatase technique in dermatopathology. J Cutan Pathol 1987; 14: 6-9.

Address for correspondence

Yoshihiro Ikura
Department of Pathology
Takatsuki General Hospital
1-3-13, Kosobecho
Takatsuki 569-1192, Japan
tel. & fax: +81 72 684 0295
e-mail: ikura@ajk.takatsuki-hp.or.jp
Copyright: © 2016 Polish Association of Pathologists and the Polish Branch of the International Academy of Pathology This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) License (http://creativecommons.org/licenses/by-nc-sa/4.0/), allowing third parties to copy and redistribute the material in any medium or format and to remix, transform, and build upon the material, provided the original work is properly cited and states its license.
Quick links
© 2022 Termedia Sp. z o.o. All rights reserved.
Developed by Bentus.