Original Research Article Skin Adnexal Tumors- An Institutional Experience 1 2* 3 4 5 6 Rekha M Haravi , Roopa K N , Priya Patil , Rujuta Datar , Meena N Jadhav , Shreekant K Kittur 1,5Associate Professor, 2Post Graduate Student, 3,4Assistant Professor, 6Professor & HOD, Department of Pathology, Belgaum Institute of Medical Sciences Dr B R Ambedkar Road, Belagavi, Karnataka – 590001, INDIA. Email: [email protected] Abstract Background: Skin adnexal tumors are a wide spectrum of benign and malignant tumors that differentiate towards one or more adnexal structures found in normal skin. The adnexal structures of skin are the hair follicles, sebaceous glands, eccrine and apocrine sweat glands. These skin adnexal tumors are often difficult to diagnose clinically. This retrospective study was undertaken to know the various histomorphological patterns of skin adnexal tumors at our institution and to determine the incidence among the genders and age groups along with the site distribution. Materials and methods: A total of 40 specimens received and diagnosed as skin adnexal tumors in the department of Pathology at Belgaum Institute of Medical Sciences, Belagavi for a period of 6 years from January 2014 to December 2019 were taken for the study. Histopathological slides prepared from tissue blocks retrieved from departmental archives were reviewed and classified according to the WHO classification 2017. Results: Out of the total 40 samples, benign tumors were 36 (90%) and malignant were 4 (10%). Largest group was the benign tumors of apocrine and eccrine differentiation (47.5%) followed by benign tumors of hair follicle differentiation (40%). Malignant tumors of sebaceous differentiation were 5%, malignant tumors of eccrine and apocrine differentiation were 2.5% and malignant hair follicle differentiation tumors were 2.5% of the total. Conclusions: Benign skin adnexal tumors were more compared to malignant tumors with most common being tumors of eccrine and apocrine origin. Keywords: Benign, histopathology, malignant, skin adnexal tumors *Address for Correspondence: Dr Roopa K N , W/O Dr Sukumara S, # 4233, Jayapriya Heights, Pipeline road, Bagalagunte, Near Mallasandra Government Hospital, Jalahalli West, Bengaluru- 560057, Karnataka, INDIA. Email: [email protected] Received Date: 23/09/2020 Revised Date: 14/10/2020 Accepted Date: 19/11/2020 DOI: https://doi.org/10.26611/1051723 This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. 2 diagnostic confirmation. Certain specific types of tumors Access this article online may be associated with some complex genetic syndromes like Cowden’s syndrome, Muir Torre syndrome, Myotonic Quick Response Code: Website: dystrophy, Skull dysostosis, and Trisomy 9.3 www.medpulse.in In Indian population, the overall incidence of skin adnexal tumors is very low.4 These tumors have variable histomorphological patterns, due to which the histological diagnosis can be challenging, yet histopathological Accessed Date: diagnosis plays the main role in the diagnosis of skin 22 February 2021 adnexal tumors. Fewer studies have been conducted on the histomorphological patterns of various skin adnexal tumors. Literature review has shown tumors of different INTRODUCTION adnexal structures predominating at different institutions. Skin adnexal tumors are a wide spectrum of benign and This study is undertaken to know the various malignant tumors that differentiate towards one or more histomorphological patterns of skin adnexal tumors at our adnexal structures found in normal skin.1 The adnexal institution and to determine the variation in incidence structures of skin are the hair follicles, sebaceous glands, among the genders and age groups along with the site eccrine and apocrine sweat glands. These skin adnexal distribution. tumors are often difficult to diagnose clinically. Histopathology and immunohistochemistry provide MATERIALS AND METHODS How to cite this article: Rekha M Haravi, Roopa K N, Priya Patil, Rujuta Datar, Meena N Jadhav, Shreekant K Kittur. Skin Adnexal Tumors- An Institutional Experience. MedPulse International Journal of Pathology. February 2021; 17(2): 31-35. https://www.medpulse.in/Pathology/ MedPulse International Journal of Pathology, Print ISSN: 2550-7605, Online ISSN: 2636-4697, Volume 17, Issue 2, February 2021 pp 31-35 Source of data: All specimens received and diagnosed as and histopathology requisition forms. Tissue blocks of skin adnexal tumors in the department of Pathology at these cases were retrieved from the departmental Belgaum Institute of Medical Sciences, Belagavi for a archives. Histopathological slides were prepared from period of 6 years from January 2014 to December 2019. these blocks and stained with hematoxylin and eosin stain Method of collection of data: The total number of and reviewed. Special stains like Periodic acid Schiff, etc. specimens received from the Departments of was done wherever required. The tumors were analyzed Dermatology and venereology, General Surgery and considering their clinical features and histomorphological various other clinical departments to the Department of patterns and classified according to the WHO Pathology and diagnosed on histopathology as skin classification 2017. The collected data was presented in adnexal tumors were taken for this study. All clinical the form of percentage or proportions and graphs. details of the cases were noted down from the case files OBSERVATION AND RESULTS Figure 1 A C B Figure 2 Figure3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 1: Case distribution based on appendageal differentiation; Figure 2: Microphotograph showing Pilomatrixoma with osseous metaplasia (H&E100x) ; Figure 3: Microphotograph showing Clear cell Hidradenoma (H&E 100x); Figure 4: Microphotograph showing Syringocystadenoma papilliferum (H&E 100x). Inset sowing plasma cells (H&E 400x); Figure 5: Microphotograph showing Primary Cutaneous Mucinous Carcinoma (H&E 100x). Inset (PAS 100x; Figure 6: Microphotograph showing PCMC – IHC- A: ER positive (400x), B: PR positive (400x), C: CK 7 positive (400x); Figure 7: Microphotograph showing Sebaceous Carcinoma (H&E 400x) During the study period, 40 adnexal tumors of skin were 3 (7.5%) cases were diagnosed as tumors of sebaceous diagnosed on histopathological examination. Out of these, differentiation. Out of these 3 cases, 1 case was 37 cases (92.5%) were benign and 3 (7.5%) cases were Sebaceoma (2.5%) and the other 2 cases were sebaceous malignant. There were 19 (47.5%) benign sweat gland carcinoma (5%). (Table 1, Figure 1). tumors and 1 (2.5%) malignant sweat gland tumor. On the basis of their line of differentiation, the most Benign tumors included Clear cell hidradenoma (n=7, common group of tumors was of eccrine/ apocrine 17.5%), Poroma (n=1, 2.5%), Syringocystadenoma differentiation. (Table 1, Figure 1). papilliferum [SCAP] (n=5, 12.5%), papillary eccrine Most common age group affected ranged from 21-40 adenoma (n=2, 5%), Cylindroma (n=2, 5%) and apocrine years (35%) followed by 41-60 years of age (30%). Male: hydrocystoma (n=2, 5%). Malignant tumor was primary Female ratio was found to be 1.5: 1 with slight male cutaneous mucinous carcinoma [PCMC] (n=1, 2.5%). preponderance. Head and neck was the most common site (Table 1). affected (57%) with predominance in the facial region There were 17 (42.5%) benign tumors of hair follicle followed by trunk (17%), Upper limb (13%), Lower limb differentiation, out of which Pilomatrixoma constituted (10%) and Genitalia (3%). the majority (n=16, 40%) followed by proliferating trichilemmal tumor (n=1, 2.5%). (Table 1, Figure 1) MedPulse International Journal of Pathology, Print ISSN: 2550-7605, Online ISSN: 2636-4697, Volume 17, Issue 2, February 2021 Page 32 Rekha M Haravi, Roopa K N, Priya Patil, Rujuta Datar, Meena N Jadhav, Shreekant K Kittur DISCUSSION Table 1: Comparison of incidence of skin adnexal tumors in various published studies with the present study 1 2 3 7 Studies Kaur et al Radhika et al Sahu et al Garima et al Present study Commonest age 20-39 20-30 21-30 41-60 21-40 group(in years) Male: Female 1.03:1 0.7:1 1.7:1 1:1.3 1.5:1 Commonest site Head & Neck Head & Neck Scalp Head & Neck Head & Neck Benign tumors 82.72 % 77.14 % 78.33 % 96.5 % 92.5 % Malignant tumors 17.28 % 29.63 % 21.66 % 3.5 % 7.5 % Commonest line of Hair follicle Sweat gland Sweat gland Sweat gland Sweat gland differentiation (39.09 %) (48.57 %) (45 %) (49.12 %) (50 %) Commonest Pilomatrixoma (28.2%) Nodular hidradenoma, Poroma Pilomatrixoma Pilomatrixoma benign tumor Sebaceous nevus (14.2%each) (16.66 %) (26.2 %) (40 %) Commonest Sebaceous carcinoma Sweat gland Sebaceous Sebaceous Sebaceous malignant tumor (11.8%) carcinoma(11.4%) carcinoma(13.33%) carcinoma(3.5%) carcinoma (5 %) Differentiation Benign eccrine Clear cell hidradenoma 15.45 % 14.28 % 5 % 22.8 % Poroma 3.63 % - 16.66 % 3.5 % Syringoma 5.45 % 2.8 % 11.66 % - Spiradenoma 1.8 % 8.5 % 3.33 % 17.54 % Chondroidsyringoma 3.63 % - - - Malignant eccrine Primary mucinous - - - - carcinoma Porocarcinoma 0.9 % - 3.33 % - Hidradenocarcinoma - - 3.33 % - Adenoid cystic 2.72 % - 1.66 % - carcinoma Benign apocrine Syringocystadenoma 0.9 % - - - papilliferum Papillary eccrine - - - - adenoma Cylindroma 1.8 % 2.85 % - 1.75 % Apocrine - - - - hydrocystoma Hidradenoma - 8.5 % - 3.5 % papilliferum Malignant Adenocarcinoma 0.9 % - - - apocrine Hair follicle Pilomatrixoma 28.2 % 5.7 % 11.66 % 26.31 % Proliferating 2.72 % - 3.33 % 1.75 % (Benign) trichilemmal tumor Trichofolliculoma 1.81 % 2.8 % - 1.75 % Trichoblastoma - - 3.33 % - Hair follicle Pilomatrix carcinoma 0.9 % - - - (Malignant) Tricholemmal - 5.7 % - - carcinoma Benign sebaceous Sebaceoma - - 3.33 % 1.75 % Sebaceous adenoma 0.9 % - 15 % 1.75 % Malignant sebaceous Sebaceous carcinoma 11.8 % 5.7 % 13.33 % 3.5 % Skin adnexal tumors are thought to originate from multi are found to be important contributing factors in tumors potent undifferentiated stem cells. These cells have the having genetic basis. (9) Incidence and location of tumors capability to differentiate along particular or multiple vary in different regions and institutions as documented pathways. (3, 8) Mendelian inheritance and p53 mutations by several studies.