Historical Perspective: Whiteman et al., 1995; Handfield-Jones and N. Smith, 1996

 
Also in 1995, Whiteman and coworkers58 reported on the incidence of cutaneous melanomas in children 14 years of age or younger who lived in Queensland, Australia. They identified 61 patients with melanoma during the period of their study, i.e., January 1, 1987, to June 30, 1994, and this is what they said about them:
 
"The majority of melanomas were diagnosed in children aged between 10 and 14 years; however, one case of in situ melanoma and 4 cases of invasive melanoma were reported in children younger than 10 years. The youngest child diagnosed with invasive melanoma during this period was aged 3 years. . . . These data indicate that childhood melanoma was rare in those aged less than 10 years (at about 1 case/million children/year) but increased abruptly in the 10-14 year age group to nearly 30 cases/million children/year. . . . The present study found an excess of tumours on the trunk, and fewer on the head, neck and upper limbs. Lesions below the waist were rare. Overall, there was no difference in the site distribution of melanomas between males and females among these children, in contrast to the melanoma experience of the adult population in Queensland."
 
No photomicrographs were published by Whiteman et al., but they did write these lines about the histopathologic findings in the melanomas they studied:
 
"Of the 61 melanomas diagnosed during the study period, 21 were classified as superficial melanomas (14 were invasive), 2 were nodular melanomas (both invasive), 1 was an in situ acral lentiginous melanoma and 1 was a deeply invasive desmoplastic melanoma. The remaining 36 tumours (28 of which were invasive) were not further classified by the pathologists at the time of diagnosis.
 
The depth of dermal invasion (Clark's level) was reported for 55 of the 61 melanomas. Sixteen tumours were level I (in situ) melanomas, 33 tumours were described as leve lII, 4 tumours were level III and 2 tumours were level IV. Five of the 6 unclassified melanomas were metastatic deposits or recurrences following earlier removal of unusual pigmented lesions. The only report for a primary melanoma which omitted details of Clark's level of invasion was for a desmoplastic melanoma of the scalp."
 
Handfield-Jones and Smith, in 1996,59 reported on 24 melanomas in children 16 years of age or less. They categorized the children according to age, nine of them being five years old or younger, nine being between the ages of six and 10, and six being ages 11 through 16. This is what they wrote about histopathologic findings in the melanomas in these children (Fig. 15) in an article titled, "Malignant melanoma in childhood":
 
"Histological classification of the melanomas was 'nodular' in 17 cases, 'superficial spreading' in three cases, and unclassifiable in four. Tumour cell type in all lesions included either spindle cells, epithelioid cells, or both. The lesions tended to be thick. They were Clark's level 5 in two cases, level 4 in 13 cases, level 3 in six cases, and level 2 in two cases. Breslow thickness ranged from 0.6 mm to more than 7.8 mm with a mean of 3.72 mm . . ."

View Figure  		Fig. 15  Comment: This neoplasm pictured by Handfield-Jones and N. Smith came from a 6-year-old who died of metastatic melanoma. Although some features shown here are shared by Spitz nevus, as the authors aver, this neoplasm can be diagnosed, in these photomicrographs, as a melanoma; it is asymmetrical, its base is uneven, and it is made up of aggregations of neoplastic melanocytes that vary greatly in size and shape, have assumed peculiar geometric outlines, and have become confluent in foci. In addition, the cytologic features shown at high magnification are very unlike those of Spitz's nevus, many of the nuclei being small and the cytoplasm being scant. The many mitotic figures are another indication of melanoma.
 
The criteria utilized by Handfield-Jones and Smith for distinguishing melanoma from Spitz's nevus were these:
 
"The criteria used for distinguishing MM [malignant melanoma] from Spitz naevus can be divided into architectural and cytological features. Of the architectural features, asymmetry was seen in five lesions, as shown in the superficial spreading melanoma in Figure 6. An expansile growth pattern, seen as abnormal masses of cells within a lesion, was present in eight lesions. This change can sometimes be seen more easily by using a reticulin stain. Another distinguishing feature is intralesional transformation, where the cell type changes within the tumour. Six lesions showed ulceration or surface erosion, and two showed areas of necrosis within the lesion. In some specimens, low-power examination revealed lesions resembling Spitz naevi, with no worrying features. However, at high power, frequent, atypical or deep mitoses could be seen. Figure 10 shows one such case, in which a high mitotic rate (six per high-power field) and deep mitoses were the only worrying features. This is the histology of case 13, the child who died of disseminated disease."
 
Some of the criteria employed by Handfield-Jones and N. Smith are not consonant with reality as we perceive it, among them "expansile growth pattern" (movement cannot be discerned through a microscope) and "intralesional transformation" (change cannot be recognized through a microscope). That way of thinking, which derived directly from Clark and members of his school, is an impediment to distinguishing with consistency melanoma from Spitz's nevus histopathologically.