Polythelia: Anatomic and clinical implications. Mohammad O. Selman MBChB; FIBMS.

Abstract Background: Polythelia or supernumerary on the anterior thoracic wall, 12(27.9%) on the (also called third or accessory nipple) is anterior abdominal wall and one (2.3%) was in an additional nipple occurring in the inguinal region. Only five cases (11.6%) including humans. These additional had family history of previous similar develop during embryonic life as part of conditions. abnormal development of mammary glands. Conclusion: Polythelia is a fairly common Objectives: To describe the polythelia and it’s abnormality. Men and women may have extra most frequent locations also to give a nipple, but no significant difference was perspective of polythelia in a series of detected that can be related to gender observations. And lastly to asses if there is any difference. Nevertheless presence of extra genetic inheritance present. nipples was sometimes linked to heart disease, Methods: Forty three cases of polythelia were no such relationship was noticed. All cases in collected from attendants of general practice this study had their polythelia along the milk clinic in Baghdad. The polythelia was line. Nevertheless, there had been reports on observed during routine physical examination, polythelia presenting as far away as the foot. which included examination of the chest and Keywords: polythelia, , abdomen. Supernumerary nipple. Results: From 43 cases of polythelia, males constituted 23 (53.5%) of cases. Regarding the IRAQI J MED SCI, 2010; VOL.8 (4):53-56 anatomical location of polythelia, 2(4.65%) were on the anterior axillary fold, 28(65.1%)

Introduction Polythelia or supernumerary underlying mesenchym. Here it forms nipple (also called third or accessory 16 to 24 sprouts, which in turn give nipple) is an additional nipple rise to small, solid buds. By the end of occurring in mammals including the prenatal life, the epithelial sprouts humans. These additional nipples are canalized and form the lactiferous develop during embryonic life as part ducts, and the buds form small ducts of abnormal development of mammary and alveoli of the gland. Initially the glands (1). lactiferous ducts open into a small The first indication of mammary epithelial pit. Shortly after birth, this glands is found in the form of a band pit is transformed into the nipple by like thickening of epidermis along the proliferation of underlying mammary line or . In a mesenchyme (2). 7-week embryo this line extends on Polythelia refers to the presence of each side of the body from the base of an additional nipple alone while the forelimb to the region of the hind polymastia denotes the presence of limb. Although the major part of the additional mammary gland. Polythelia mammary line disappears shortly after often looks like moles or freckles and it forms, a small portion in the thoracic do not always have a connection with region persists and penetrates the tissue or milk ducts (3). Polythelia is classified into eight Dept. Human Anatomy, College of levels of completeness from a simple Medicine, Al-Nahrain University. patch of to a milk bearing breast. Address Correspondence to: Dr. Mohammad O. Selman, This study will investigate the E- mail:[email protected] condition of polythelia as regards the Received: 8th June 2010, Accepted: 25th anatomical location of the additional August 2010. nipples, the presence of family history

Iraqi Journal of Medical Sciences 53 Polythelia: Anatomic and clinical implications….Mohammad O. Selman.

of such condition in the first and • Presence of other notable systemic second degree relatives, gender diseases. differences and the possible relation to Results other diseases(4) . The total number of cases enrolled Material and Methods in this study was 43. The age was very This study was performed on 43 variable; however most of observed cases with polythelia. They were cases were in 3rd or 4th decade of life. collected from attendants of general Males constituted 23(53.5%) cases and practice clinic at Baghdad. The females were 20(46.5%). polythelia was observed during routine Regarding the anatomical location physical examination, which included of polythelia, 2(4.65%) were on the examination of the chest and abdomen. anterior axillary fold, 28(65.1%) on the Once observed, detailed information anterior thoracic wall, 12(27.9%) on were recorded about the condition in a the anterior abdominal wall and one study form which includes: (2.3%) was in the inguinal region • Personal data of name and residence (Table 1). • Age and gender Regarding the family history of • Physical examination of the such condition in first degree relatives condition, included inspection, (parents and offspring) and second palpation and fluctuation test for degree relatives (brothers and sisters) presence of fat. Data regarding only five (11.6%) had such family presence of glandular tissue, nipple, history. pigmented , fatty tissue and No notable systemic diseases were presence of hair. recognized in these cases who were • The anatomical position was seeking medical consultation for no recorded as being on anterior axillary major systemic disease. fold, thoracic wall, anterior abdominal Careful inspection was done for wall and the inguinal region (groin). the condition and palpation was • Presence of similar condition in performed to detect underlying family, including first and second glandular tissue. Two fingers degree relatives. fluctuation test was done to identify fatty material if a lumpy structure was present.

Table 1: Sites of polythelia (supernumerary nipples) in mammals including humans Total number (43) Sites of polythelia Gender AAW AAF ACW IR male 23 (53.5%) female 20 (46.5%) 12 (27.9%) 2 (4.65%) 28 (65.1%) 1 (2.3%) The abbreviations: AAW: Anterior abdominal wall, AAF: Anterior axillary fold, ACW: Anterior chest wall and IR: Inguinal region.

Discussion The aim of this study was to give a common abnormality. It is proposed perspective of the condition of that this type of congenital abnormality additional nipple or polythelia in a occurs at rate of 1 in 18 human (5). series of observation. According to our Larger study is required to observations, polythelia is a fairly investigate the prevalence of this

Iraqi Journal of Medical Sciences 54 Polythelia: Anatomic and clinical implications….Mohammad O. Selman. condition since many mistake it as inheritance or predisposition to this mole, navus, freckle or pigmented skin condition. condition. Men and women may have In this study no concomitant extra nipple. In this work no significant pathological conditions with polythelia difference was detected that can be were found and unable to link it to related to gender difference. other disease entities. Nevertheless All the cases included in this study presence of extra nipples was had no glandular tissue, so they were sometimes linked to heart disease, and not polymastia. The observed a possible relationship with mitral additional nipples can be designated as valve prolapse had been proposed (10), pseudo mamma when they possess a no such relationship was noticed in the nipple, areola and fat tissue. study group. They are considered classical However in general any breast polythelia when they are just a nipple. tissue, whether it appears in the Polythelia areolaris, when only an standard location or elsewhere is areola is present and polythelia pilosa vulnerable to the same diseases that when it consists of a conglomerated can affect typical breast tissue. Extra patch of hair (6). mammary Paget's disease of the nipple From the anatomical point of can affect these additional nipples (6). view, the most frequent location of In most people, extra nipples are polythelia is the thorax. Commonly an benign and may never be noticed. But additional nipple was found to be if they change, develope a lump, rash present inferior and medial to the or discharge, they should be taken location of the genuine nipple. seriously, otherwise polythelia may be The second most common site was surgically removed, just like a mole. on the anterior abdominal wall. Other In western folklore, an extra sites observed were along the anterior nipple was held to be indicative that axillary fold and above medial inguinal the women concerned was a witch, the region. nipple used to suckle the devil! All cases in this study had their References polythelia along the milk line. 1. Fuchs E. Epidermal differentiation: the Nevertheless, there had been reports on bare essential. J. Cell Biol. 1990; 111: 2807- polythelia presenting as far away as the 2815. (7) 2. Sadler TW. Langman's Medical foot . Embryology 11th. Edition. Lippincott, The development of breast is Williams & Wilkins. 2010; pp. 431-432 under genetic control, and the gene 3. Rapini RP. Boolognia JL & Jorizzo JL. coding for this process is called Dermatology st. Louis. Mosby, 2007. 4. Newman M. Supernumerary nipples. Am. Scaramanga gene. This gene is Fam. Physician, 1988; 38:183-188. responsible for the expression of a 5. Beller F. Development and anatomy of the protein called Neuregulin-3 (NRG3) breast. In Mitchell: GWJr, Bassett (eds): The which provides a signal to embryonic female breast and its disorders. Baltimore. cells to differentiate into mammary Williams & Wilkins, 1990. cells (8). Although polythelia tends to 6. Ostas MO & Gurer MA. Dermoscopic (9) features of accessory nipples. International occur sometimes in families , it is Journal of Dermatology, 2007; 46/10:1067- more likely to develop at random. Only 1068. Published Online. five cases with familial background in 7. "Pseudomammaon the foot: An unusual the form of the presence of polythelia presentation of supernumerary breast tissue". http: //dermatology. cdlib. was found in first and second degree Org/124/case_presentations / psudomamma / relatives, in the whole study group. conde. Html. Retrived 2007-12-03 This finding does not support a genetic

Iraqi Journal of Medical Sciences 55 Polythelia: Anatomic and clinical implications….Mohammad O. Selman.

8. Howard BA. The role of NRG3 in mammary development. J. Mammary Gland Biol. Neoplasia, 2008; 13/2: 195-203. Published Online. 9. Galli-Tsinopoulou A, Krohn C and Schmidt H: familial polythelia over three generations with polymastia in the youngest girl. Eur.J.Pediatr, 2002; 160(6): 375-377. 10. Rajaratnam K, Kumar PD, Sahasvanam KV: Supernumerary nipple as a cutaneous marker of mitral valve prolaps in Asian Indians. Am. J. Cardiol, 2000; 86/6: 695-697.

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