Indian Journal of Paediatric Dermatology

: 2021  |  Volume : 22  |  Issue : 2  |  Page : 186--188

A painful mass on the scalp: An uncommon tumor at an uncommon site

Smita S Ghate1, Priyanka Arun Kowe2, Sandip Agrawal3, Rachita S Dhurat1,  
1 Department of Dermato-Venereo-Leprology, Lokmanya Tilak Municipal Medical College and Hospital, Mumbai, Maharashtra, India
2 Department of Dermato-Venereo-Leprology, Government Medical College and Hospital, Nagpur, Maharashtra, India
3 Department of Dermatology-Venereo-Leprology, Indira Gandhi Government Medical College, Nagpur, Maharashtra, India

Correspondence Address:
Priyanka Arun Kowe
Lokmanya Tilak Muncipal Medical College and Hospital, Dr Babasaheb Ambedkar Road, Sion (West), Mumbai - 440 022, Maharashtra

How to cite this article:
Ghate SS, Kowe PA, Agrawal S, Dhurat RS. A painful mass on the scalp: An uncommon tumor at an uncommon site.Indian J Paediatr Dermatol 2021;22:186-188

How to cite this URL:
Ghate SS, Kowe PA, Agrawal S, Dhurat RS. A painful mass on the scalp: An uncommon tumor at an uncommon site. Indian J Paediatr Dermatol [serial online] 2021 [cited 2021 May 10 ];22:186-188
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Glomus tumors are rare benign cutaneous vascular neoplasms arising from modified vascular smooth muscle cells, called as glomus cells, present in glomus apparatus located at acral areas such as under surface of nail plate, tips of fingers or toes. It is also termed as a hamartoma or a neoplasm of neuromyoarterial glomus consisting of multiple dilated vascular channels surrounded by proliferating glomus and nerve cells (Sucquet-Hoyer canal) that plays an important role in the temperature regulation.[1] We present a young girl with mildly painful reddish to purple swelling over the scalp of long duration. On histopathology, a characteristic arrangement of large polygonal to spindle-shaped monomorphic cells around the blood vessel leads to confirmatory diagnosis of epithelioid variant of glomus tumor located at an unusual site. The tumor was excised completely, with no evidence of recurrence after 2 years of follow-up. Yanagi and Matsumura, in 2005, have reported for the first time a case of scalp epithelioid glomus tumor.[2] To the best of our knowledge, this is the second case of scalp epithelioid glomus tumor.

A 13-year-old girl presented with swelling over the scalp for 4 years. It started as a small asymptomatic red-to-purple mass on the right side of her scalp which over the period of 4 years gradually increased in size to Attain the present size. Pain on pressure was noted since one month. There was neither any history of trauma preceding the onset of lesion nor it was associated with seasonal variation in the size of the tumor. Examination revealed an erythematous, firm to cystic mass, mildly tender, of size 0.5 cm × 0.5 cm over the right parietal area of the scalp [Figure 1]. We kept the differential diagnosis of pilomatricoma, hydrocystoma, and epidermoid cyst. The transillumination test was negative, and there was no central punctum in the swelling and no evidence of ulceration of the overlying skin. Ultrasound of the swelling revealed well-defined anechoic mass lesion in the subcutaneous tissue with thickened walls and pin-point calcification. The overlying dermis was normal and showed the presence of mass effect. Thus, sonography was suggestive of either epidermoid cyst or pilomatricoma. Magnetic resonance imaging (MRI) could not be performed due to the high cost. Excisional biopsy of the tumor revealed a well-circumscribed mass located deep in the dermis [Figure 2]. The tumor composed of sheets of monomorphic cells which are polygonal to spindle shaped with irregular nuclei and eosinophilic cytoplasm surrounded by well-defined margin [Figure 3]a and [Figure 3]b. These are called glomus cells which are characteristically present surrounding multiple dilated blood vessels. For further confirmation, immunohistochemistry markers such as smooth muscle actin, vimentin, desmin, CD34, and CD31 were advised, but could not be done due to financial constraints. Thus, based on histopathological findings, the final diagnosis of epithelioid variant of glomus tumor was made. The patient reported no evidence of recurrence or complication for the past 2 years following excisional biopsy [Figure 4].{Figure 1}{Figure 2}{Figure 3}{Figure 4}

Glomus tumors are uncommon vascular tumors that may present at birth and seldom appear during infancy. incidence may increase gradually from the age of 7 years. Presentation in adults may occur at the third to fourth decade with equal sex distribution.[3] First described by Woods in 1812, as a painful swelling of subcutaneous tissue arising from normal glomus apparatus, glomus apparatus is a part of the dermal layer of the skin involved in the regulation of the body temperature. It consist of central coiled canal, the Sucquet–Hoyer canal lined by endothelium and many layers of glomus cells.[4] Glomus cells are modified vascular smooth muscle cells. They are round, regular cells containing central darkly stained round-to-oval nuclei surrounded by eosinophilic cytoplasm. These tumors are positive for smooth muscle actin, vimentin and negative for desmin, CD34, CD31, factor 8 on immunohistochemistry.[2],[5] The glomus tumor may present as solitary or multiple lesions. They are characterized by small, reddish-to-purple severely painful mass. Pain is excruciating, spontaneous, or aggravated by pressure and cold. There may be history of trauma preceding the tumor.[6] The most common sites of involvement are on the tip of digits or undersurface of the nail plate where they are severely painful. Other sites include the penis, head, extremities, and rarely in the internal organs such as the stomach, lung, trachea, bone small intestine, pterigoid fossa, and mediastinum.[4] At these sites, tumor may be large and painless. Multiple tumors are mostly familial with autosomal dominant inheritance having locus on chromosome 1p21–p22 and more commonly seen in children than in adults.[5] MRI is the most sensitive imaging modality for evaluating the extent of glomus tumor and defining its relationship to other anatomic structures. The tumor may be “solid glomus tumor” when glomus cells predominate in the lesion, it may be “glomangioma” when the blood vessels predominate with few glomus cells and “glomangiomyoma” when elongated smooth muscle cells predominate.[7] The tumor cells and blood vessels are surrounded by fibrous stroma. Lack of pleomorphism and their uniformity are the characteristics of this tumor.[4] The classical glomus tumor is a well-circumscribed or encapsulated dermal tumor which may extend into the subcutis. It consists of solid aggregates of glomus cells surrounding vessels. Pulitzer et al., in 1995 described “epithelioid glomus tumor” as a rare histopathological variant of solitary glomus tumor characterized by large polygonal to spindle-shaped cells with abundant eosinophilic cytoplasm and large irregularly shaped nuclei. He reported these findings in five patients. It is hypothesized that tissue senescence plays a role to cause these epithelioid changes on histopathology.[8] Our case also has similar histopathological features which resembles an epithelioid variant. The various locations of epithelioid glomus tumor reported in the literature include legs, arms, scalp, shoulder, uterine cervix [Table 1]. These are uncommon sites and differ from the common sites of solitary glomus tumor. Skin biopsy and immunohistochemistry are required for definitive diagnosis as epithelioid glomus tumor may be mistaken for other spindle-cell lesions histologically such as leiomyoma, schwannoma, and hemangiopericytoma.[8],[9] Treatment consists of complete surgical excision of tumor mass. Recurrence is rare after excision.{Table 1}

Thus, one should be vigilant when an uncommon tumor presents at a unique location posing a diagnostic challenge. Thus, we highlight uncommon histopathological variant of glomus tumor occurring at an uncommon site.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.


1Rao AG, Indira D, Kamal J. Extra digital glomangioma. Indian J Dermatol 2010;55:397-8.
2Yanagi T, Matsumura T. Scalp epithelioid glomus tumor: A rare location. Acta Derm Venereol 2006;86:267-8.
3Calonje E. Soft tissue tumours and tumor-like conditions. In: Griffiths C, Barker J, Bleiker T, Chalmer R, Creamer D, editors. Rook's Textbook of Dermatology. 9th ed. Oxford: Wiley Blackwell; 2016. p. 137.44.
4Weedon D. Vascular tumors. In: Weedon D, editor. Skin Pathology. 3rd ed. London: Churchill-Livingston; 2010. p. 907-8.
5Pereira RR, Nayak CS, Topal A, Dhurat RS. An unusually painful nodule. Indian J Dermatol 2012;57:249-50.
6Requena L, Sangueza OP. Cutaneous vascular proliferation. Part II. Hyperplasias and benign neoplasms. J Am Acad Dermatol 1997;37:887-919.
7Khandpur S, Ramam M. Skin tumors. In: Valia RG, Valia AR, editors. IADVL Textbook of Dermatology. 3rd ed., Vol. 2. Mumbai: Bhalani Publishing House; 2008. p. 1516.
8Pulitzer D R, Donald R., Pamela C. Martin, Richard J. Reed. Epithelioid glomus tumor. Human pathology; 1995;26.9:1022-1027.
9Aynardi JT, Kim SH, Barroeta JE. Epithelioid glomus tumor of the uterine cervix: A case report and review. Int J Gynecol Pathol 2016;35:275-8.