Poroma

For the local-level government area of Papua New Guinea, see Poroma Rural LLG.
Poromas are benign tumors of the distal portion of sweat gland ducts.

Poromas are rare, benign, cutaneous adnexal tumors.[1] Cutaneous adnexal tumors are a group of skin tumors consisting of tissues that have differentiated (i.e. matured from stem cells) towards one or more of the four primary adnexal structures found in normal skin: hair follicles, sebaceous sweat glands, apocrine sweat glands, and eccrine sweat glands.[2] Poromas are eccrine or apocrine sweat gland tumors derived from the cells in the terminal portion of these glands' ducts.[3] This part of the sweat gland duct is termed the acrosyringium and had led to grouping poromas in the acrospiroma class of skin tumors (syringofibroadenomas and syringoacanthomas are classified as acrospiromas).[3][4][5][6] Here, poromas are regarded as distinct sweat gland tumors that differ from other sweat gland tumors by their characteristic clinical presentations, microscopic histopathology, and the genetic mutations that their neoplastic cells have recently been found to carry.[7]

As currently viewed, there are 4 poroma variants based on their predominant cell types and extent of their tumor tissues presence in the epidermis and dermis: 1) Hidroacanthoma simplex poromas are confined to the epidermis, i.e. uppermost layer of the skin. 2) Dermal duct poromas are confined to the dermis, i.e. layer of skin between the epidermis and subcutaneous tissues.[8] 3) Hidradenomas have recently been sub-classified into two groups; 95% are termed clear cell hidradenomas and have features suggesting that they derive from apocrine sweat glands while the remaining 5% are termed poroid hidradenomas and have features suggesting that they derive from eccrine sweat glands.[9] And 4) eccrine poromas are eccrine sweat gland tumors that consist of three cell types (see Histopathology section).[1][3]

Poromas usually occur as single, small, skin tumors that develop in middle aged to elderly individuals. They may occur anywhere on the body, but are most commonly seen on the head, neck, and extremities.[3] They seldom cause symptoms.[8] While benign, long-standing poromas have, in very rare cases, progressed to malignant forms termed porocarcinomas.[8] Poromas are treated by excision; their removal is almost always curative.[3]

  1. ^ a b Agaimy A (May 2022). "Fusion-positive skin/adnexal carcinomas". Genes, Chromosomes & Cancer. 61 (5): 274–284. doi:10.1002/gcc.23031. PMID 35167714. S2CID 246864699.
  2. ^ Zaballos P, Gómez-Martín I, Martin JM, Bañuls J (October 2018). "Dermoscopy of Adnexal Tumors". Dermatologic Clinics. 36 (4): 397–412. doi:10.1016/j.det.2018.05.007. PMID 30201149. S2CID 52185272.
  3. ^ a b c d e Miller AC, Adjei S, Temiz LA, Gill P, Siller A, Tyring SK (January 2022). "Dermal Duct Tumor: A Diagnostic Dilemma". Dermatopathology. 9 (1): 36–47. doi:10.3390/dermatopathology9010007. PMC 8883970. PMID 35225875.
  4. ^ Sawaya JL, Khachemoune A (September 2014). "Poroma: a review of eccrine, apocrine, and malignant forms". International Journal of Dermatology. 53 (9): 1053–61. doi:10.1111/ijd.12448. PMID 24697501. S2CID 45591988.
  5. ^ Ackerman, AB, ed. (1990). Ackerman's Histologic Diagnosis of Neoplastic Skin Diseases, a Method by Pattern Analysis. Vol. 1. Philadelphia, PA: Lea & Febiger. pp. 113–185.
  6. ^ Casper, DJ; Glass, LF; Shenefelt, PD (Nov 2011). "An Unusually Large Eccrine Poroma: A Case Report and Review of the Literature". Cutis. 88 (5): 227–229. PMID 22272484.
  7. ^ Macagno N, Sohier P, Kervarrec T, Pissaloux D, Jullie ML, Cribier B, Battistella M (January 2022). "Recent Advances on Immunohistochemistry and Molecular Biology for the Diagnosis of Adnexal Sweat Gland Tumors". Cancers. 14 (3): 476. doi:10.3390/cancers14030476. PMC 8833812. PMID 35158743.
  8. ^ a b c Sekine S, Kiyono T, Ryo E, Ogawa R, Wakai S, Ichikawa H, Suzuki K, Arai S, Tsuta K, Ishida M, Sasajima Y, Goshima N, Yamazaki N, Mori T (May 2019). "Recurrent YAP1-MAML2 and YAP1-NUTM1 fusions in poroma and porocarcinoma". The Journal of Clinical Investigation. 129 (9): 3827–3832. doi:10.1172/JCI126185. PMC 6715383. PMID 31145701.
  9. ^ Lim JS, Kwon ES, Myung KB, Cheong SH (June 2021). "Poroid Hidradenoma: A Two-Case Report and Literature Review". Annals of Dermatology. 33 (3): 289–292. doi:10.5021/ad.2021.33.3.289. PMC 8137338. PMID 34079192.