Journal of

Mahdi Ghoncheh ^*

MD, Assistant Professor of Plastic and Reconstructive Surgery, Birjand University of Medical Sciences, Birjand, Iran

Received: October 25, 2017                    Revised: October 27, 2018         Accepted: November 28, 2018

Dear Editor

On September 2018, a case report titled “Squamous cell carcinoma arising from a sebaceous cyst” was published in the “Journal of Surgery and Trauma” (volume 6, issue 2) (1). It was an interesting article; however, I think when dealing about such rare tumors, it is important to be aware of other diseases, such as proliferating trichilemmal cysts (PTC) that maybe confused with squamous cell carcinoma  arising from a cyst. Trichilemmal (pilar) cysts are common in the scalp. These cysts originate from the outer root sheath of the hair follicles. Although trichilemmal cysts are benign, they can be transformed to PTC as a result of trauma and inflammation (2). The PTCs appear as intradermal masses with a size range of 1-10 cm. They may affect the overlying skin through fistulization or leave it intact. There are some reports regarding PTCs as fungating tumors with a diameter of 25 cm (3, 4). The PTCs can also have an invasive and malignant behavior, and therefore be called malignant PTCs (MPTCs). The MPTCs are reported to be accompanied with local invasion, metastasis to the lymph nodes,
and distant metastases (5). Treatment of
benign PTC involves a simple excision; however, the management of MPTCs requires surgical procedures with a safe excision margin of 1 cm (6, 7). Mohs micrographic surgery may increase the chance of the complete removal of the tumor (8). In addition to the excision of the tumor with a wide margin, other therapeutic modalities, such
as lymph node dissection, radiotherapy, and chemotherapy, should be also considered for the treatment of MPTC (3, 8-10). In metastatic cases resistant to the above therapies, ethanol injection into the lesions has been used to control the disease (11).

References

1.     Kuvat SV. Squamous cell carcinoma arising from a sebaceous cyst, case report. J Surg Trauma. 2009; 6(2):71-2.

2.     Kim UG, Kook DB, Kim TH, Kim CH. Trichilemmal carcinoma from proliferating trichilemmal cyst on the posterior neck. Arch Craniofac Surg. 2017; 18(1):50-3. PMID: 28913304 DOI: 10.7181/acfs.
2017.18.1.50

3.     James WD, Dirk Elston MD, McMahon PJ. Andrews’ disease of the skin. 12th ed. Philadelphia: Elsevier; 2016.

4.     Satyaprakash AK, Sheehan DJ, Sangüeza OP. Proliferating trichilemmal tumors: a review of the literature. Dermatol Surg. 2007; 33(9):1102-8. PMID: 17760602 DOI: 10.1111/j.1524-4725.2007.33225.x

5.     Ye J, Nappi O, Swanson PE, Patterson JW, Wick MR. Proliferating pilar tumors: a clinicopathologic study of 76 cases with a proposal for definition of benign and malignant variants. Am J Clin Pathol. 2004; 122(4):566-74. PMID: 15487455 DOI: 10.1309/
21DK-LY2R-94H1-92NK

6.     Leppard BJ, Sanderson KV. The natural history of trichilemmal Cysts. Br J Dermatol. 1976; 94(4):379-90. PMID: 1268052

7.     Shet T, Rege J, Naik L. Cytodiagnosis of simple and proliferating trichilemmal cysts. Acta Cytol. 2001; 45(4):582-8. PMID: 11480722 DOI: 10.1159/
000327868

8.     Cecchi R, Rapicano V, De Gaudio C. Malignant proliferating trichilemmal tumour of the scalp managed with micrographic surgery and sentinel lymph node biopsy. J Eur Acad Dermatol Venereol. 2008; 22(10):1258-9. PMID: 18422538 DOI: 10.1111/j.1468-3083.2008.02611.x

9.     Park BS, Yang SG, Cho KH. Malignant proliferating trichilemmal tumor showing distant metastases. Am J Dermatopathol. 1997; 19(5):536-9. PMID: 9335249

10. Hayashi I, Harada T, Muraoka M, Ishii M. Malignant proliferating trichilemmal tumour and CAV (cisplatin, adriamycin, vindesine) treatment. Br J Dermatol. 2004; 150(1):156-7. PMID: 14746636

11. Takenaka H, Kishimoto S, Shibagaki R, Nagata M, Noda Y, Yasuno H. Recurrent malignant proliferating trichilemmal tumour: local management with ethanol injection. Br J Dermatol. 1998; 139(4):726-9.