GIANT SCALP MELANOMA

Year 2016, Volume: 38 Issue: 3, 81 - 82, 24.09.2016

Emine Böyük Işıl Bulur Zeynep Nurhan Saraçoğlu Özlem Erdem

Abstract

To the Editor,

A 54-year-old female presented with a 4-month history of
extensive dark-colored lesions on her scalp. The pathology result of a previous
biopsy from her scalp performed by a general surgeon a year ago had been
congenital melanocytic nevus. Dermatological examination showed confluent
blue-grey, dark brown macules, papules and nodules covering most of the left
parietofrontotemporal scalp in an area measuring 15x30 cm in size (Figure 1a).
There were also satellite lesions of varying diameters on the ear, anterior
trunk and one pigmented lesion of the oral mucosa. Dermoscopic analysis of the
lesions revealed asymmetry of color and structure, multicomponent global
pattern, irregular dots and globules and bluish-white color (Figure 1b).

Histopathologic examination of three 4-mm punch biopsies from
the patient’s scalp revealed atypical melanocytic lesions with findings that
were not adequate to confirm melanoma. Total excision of the scalp lesion was
not approved by plastic surgery. The total excision material of the pigmented
lesion on her anterior trunk was referred to another pathologist and revealed
superficial spreading melanoma with Breslow thickness of 1 mm, Clark level of 3
and mitotic rate of 2/mm² (Figure 1c). In addition, pulmonary metastases were
detected by total body positron emission tomography-computed tomography
(PET-CT). The case was accepted as T1N3M1 inoperable metastatic malign melanoma
originating from the scalp lesion. Vemurafenib treatment was started by medical
oncology. However, the patient developed nodules and ulcerations, cervical
lymph node metastasis and vena cava superior syndrome during the treatment and
died nine months after the diagnosis.

Giant melanoma is a rare presentation of cutaneous melanomas.
A literature search revealed 18 previous patients with giant melanoma with only
three originating from the scalp (1-4).

Most giant melanoma cases have no precursor lesion but the
lesion developed in a congenital nevus in two cases and from a previous
melanocytic nevus in another two cases (5). No precursor lesion was found in
three cases with giant scalp melanoma (1, 3, 4). On the other hand, our patient
described a pigmented lesion on her scalp since childhood and a biopsy from the
lesion had revealed a congenital melanocytic nevus.

Giant melanomas usually present as a vegetative tumor with
high Breslow thickness. Two of the three patients with a giant scalp melanoma
in the literature presented with a vegetative tumor, and the other one
presented with confluent purple-blue-gray macules, papules and nodules as in
our patient (1, 3, 4).

Excisional
biopsy from the anterior trunk in our case revealed superficial spreading
melanoma with a Breslow thickness of 1 mm while three punch biopsies from the
scalp were not sufficient to confirm melanoma. The punch biopsy method might
not be helpful in the diagnosis of some giant melanomas, probably due to
sampling errors. Dermoscopy is also generally inadequate in identifying the
suspicious areas in these cases. We therefore recommend a large incisional biopsy
or excisional biopsy instead of punch biopsy in giant melanomas to avoid delays
in diagnosis

Keywords

scalp melanoma

References

• 1. Ching, J. A., & Gould, L. (2012). Giant scalp melanoma: a case report and review of the literature. Eplasty, 12.
• 2. Martínez‐Cabriales, S. A., Ayala‐Cortés, A. S., Vázquez‐Martínez, O. T., Welsh‐Lozano, O., Miranda‐Maldonado, I., & Ocampo‐Candiani, J. (2014). A neglected giant metastatic melanoma. Journal of the European Academy of Dermatology and Venereology.
• 3. Müller, C. S., Hinterberger, L., Vogt, T., & Pföhler, C. (2011). Giant melanoma of the scalp–discussion of a rare clinical presentation. BMJ case reports, 2011, bcr1220103643.
• 4. Panajotovic, L., Ðordevic, B., & Pavlovic, M. D. (2007). A giant primary cutaneous melanoma of the scalp–can it be that big?. Journal of the European Academy of Dermatology and Venereology, 21(10), 1417-1418.
• 5. di Meo, N., Stinco, G., Gatti, A., Errichetti, E., Bonin, S., Albano, A., & Trevisan, G. (2014). Giant melanoma of the abdomen: case report and revision of the published cases. Dermatology online journal, 20(7).