A 14‐year‐old white boy was born with a blue macula affecting the right inferior eyelid and the subpalpebral region. According to his mother, the lesion began to grow in size when he was 4 years old and began to infiltrate 7 years prior to presentation. No mongolian spot was detected at birth. Other than his facial appearance, the child had no complaints.
Dermatological examination showed a wide, blue‐coloured lesion, measuring 10 cm×11 cm at its maximum diameter, occupying the right half of the face. The lesion was infiltrated and presented some isolated nodules and several small, dark‐blue papules measuring 0.2–0.3 cm in diameter. A hard tumour, measuring 4.5 cm×3.5 cm, was present in the lower right eyelid. The upper eyelid and the supra‐palpebral area also showed a blue discolouration. Oral examination showed an extensive, infiltrated blue lesion in the right jugal mucosa. The child has severe facial asymmetry (fig 1). No sign of any other blue naevus was seen on his body. No superficial lymphadenopathy was detected. A bluish discolouration was observed in the bulbar and tarsal conjunctivae. No other abnormalities were seen in the ophthalmological examination. Visual acuity and tonometry were normal. Chest x ray was normal. Magnetic resonance imaging and tomography showed infiltration of the retrobulbar and periorbital soft tissues and the orbital bone, with a widening of the orbital fissure. The tumour filled the right maxillary sinus, projecting into the nasal cavity. The ethmoidal sinus on the same side had also been infiltrated (fig 2). The optic nerve and the extrinsic ocular muscles were not infiltrated. Owing to the degree of infiltration of the tumour, this case was considered inoperable. After 8 months of follow‐up, the child had no other complaints.
Figure 1Facial asymmetry caused by an infiltrative giant blue naevus. Presence of a tumour in the lower eyelid.
Figure 2Tomography (section of 5 mm at the level of the orbital region). Note infiltration present in the retrobulbar and periorbital soft tissues, in the orbital bones and in the right maxillary and ethmoidal sinuses.
Biopsy performed from the tumour of the lower eyelid showed melanin‐laden dendritic melanocytes and amelanotic or paucimelanotic fusiform cells with eosinophilic cytoplasm arranged in varying patterns (fig 3). The tumour affected the lower dermis, the subcutaneous fat and the subjacent skeletal muscle. Highly cellular nests of amelanotic round cells with vacuolated cytoplasm, and vesicular nuclei with small nucleoli were seen (fig 4). No mitosis, necrosis or nuclear pleomorphism was seen. Another biopsy was performed through the jugal mucosa including bone and the tumour of the maxillary sinus. Histologically, appearance of the jugal mucosa was similar to that of the biopsy described earlier. The bone marrow was infiltrated with heavily pigmented melanocytes (fig 5) that after blanching with potassium permanganate showed cells with round or oval bland nuclei and vacuolated cytoplasm. The tumour showed compactly distributed, non‐pigmented and non‐pleomorphic fusiform cells, the nuclei of which had no prominent nucleoli (fig 6). No necrosis or mitosis was observed. Immunohistochemical analysis of the tumour in the non‐pigmented areas, using the immunophosphatase technique (streptavidin–biotin system), showed that the tumour cells were MIB‐1‐and CD34‐negative but were positive with HMB45, anti‐S‐100 protein and A‐103. Melan A was weakly and focally expressed in the cells of blue naevus. In 10 high‐power fields (40× objective) no positive MIB‐1 cells were identified in the three biopsies (fig 7).
Figure 3Tumour of the maxillary sinus showing area of increased cellularity, but without cellular pleomorphism. Haematoxylin and eosin, ×200.
Figure 4Greater magnification of fig 3. Round cells compactly disposed. Haematoxylin and eosin, ×200.
Figure 5Bone marrow infiltrated by heavily pigmented melanocytes. Haematoxylin and eosin, ×50.
Figure 6Tumour of the maxillary sinus showing increased cellularity but without cellular pleomorphism. Haematoxylin and eosin, ×320.
Figure 7Cells of the tumour of the maxillary sinus. No nuclei stained with MIB‐1, ×320.