Melanoma masquerading as Spitz nevus following acute lymphoblastic leukemia

Melanomas in prepubescent children: review comprehensively, critique historically, criteria diagnostically, and course biologically

Our series was comprised of 11 children age 10 years or younger (6 were younger than age 5) with primary cutaneous melanoma. All of the melanomas occurred de novo and all metastasized; one child died. In no instance was melanoma a clinical consideration, and in none did the histopathologist who first "signed out" the case make a diagnosis of melanoma. Despite the inability of clinicians and pathologists to diagnose correctly, with repeatability, melanomas that develop in children yet to be pubescent, those neoplasms, nonetheless, are melanomas and, therefore, criteria employed currently for diagnosis of melanoma, especially clinically, must be refined in order that they be applicable equally to melanomas in pre- and postpubescents. The vaunted ABCDs (Asymmetry, Border irregular, Color variability, Diameter >6.0mm) surely do not work for melanomas that appear in children who are prepubescent. Additionally, melanomas that occur in these children have distinctly different architectural and cytopathological features from those that arise in postpubescents, often being confused as they are by conventional microscopy with a Spitz's nevus. As a rule, melanomas in prepubescent children grow much more rapidly then those in adults but, like them, have the capability to disseminate widely and cause death.

Sentinel lymph node biopsy for patients with problematic spitzoid melanocytic lesions: a report on 18 patients

BACKGROUND

Spindle and/or epithelioid melanocytic proliferations that display overlapping histopathologic features of Spitz nevus and Spitz-like melanoma are diagnostically difficult and controversial melanocytic tumors. There are reports of such lesions metastasizing to regional lymph nodes, with a few widely disseminating, resulting in death.

METHODS

The authors reviewed clinical and histopathologic data on all patients with atypical or borderline spitzoid melanocytic proliferations who underwent sentinel lymph node biopsy (SLNB). They examined how frequently histologically problematic or borderline spitzoid melanocytic lesions metastasized to sentinel lymph nodes (SLNs) and which clinical or histologic features, if any, predisposed patients to a higher risk lesion.

RESULTS

Six male patients and 12 female patients, ages 5-32 years (mean, 16 years), had tumors ranging in size from 1.2 mm to 7.9 mm (mean, 3.5 mm) in thickness. Atypical histologic features that were present most frequently included incomplete maturation (18 of 18 patients), deep dermal mitoses (16 of 18 patients), nuclear pleomorphism (10 of 18 patients), and focal sheet-like growth (10 of 18 patients). Eight of 18 patients (44%) had SLN metastasis and were offered adjuvant treatment. One of eight patients with SLN positive results who underwent regional lymphadenectomy had one additional involved lymph node. All 18 patients were alive and well with no evidence of recurrent or metastatic disease after a follow-up of 3-42 months (mean, 12 months).

CONCLUSIONS

Histologically atypical or borderline spitzoid, melanocytic tumors are diagnostically challenging and controversial melanocytic lesions, some of which represent unrecognized melanomas. SLNB aids in confirming a diagnosis of melanoma and identifies patients who may benefit from early therapeutic lymph node dissection and/or adjuvant therapy.

Molecular cytogenetics as a diagnostic tool for typing melanocytic tumors

The melanocyte can give rise to a variety of both benign and malignant lesions that differ in their clinical and histopathological appearance. It is likely that genetic changes underlie this phenotypic diversity. Comparative genomic hybridization (CGH) is a genome-wide scanning technique that permits the measurement of copy number aberrations in archival tumors. Using CGH, we have demonstrated significant differences in the frequency of chromosomal aberrations in primary cutaneous melanomas and Spitz nevi. Whereas the majority of melanomas have aberrations frequently involving chromosomes 9, 10, 7, and 6, most Spitz nevi do not show aberrations. However, a small subset of Spitz nevi show an isolated gain of the short arm of chromosome 11p. As this aberration has not been observed in melanomas, the measurement of chromosomal aberrations should be further evaluated as a diagnostic tool for ambiguous melanocytic tumors.

Management of Spitz nevi: a survey of dermatologists in the United States

BACKGROUND

There is no consensus concerning management of Spitz nevi.

OBJECTIVE

This study was carried out to ascertain how dermatologists manage Spitz nevi.

METHODS

A questionnaire was sent to 997 fellows of the American Academy of Dermatology, 284 pediatric dermatologists, and 27 directors of pigmented-lesion clinics. The results are based on the 381 questionnaires returned.

RESULTS

The vast majority of responding dermatologists (93%) recommend biopsies of suspected Spitz nevi. Of this group, 43% recommend total biopsies and 55% recommend partial biopsies; 2% would recommend either total or partial biopsies, depending on the clinical situation. Sixty-nine percent of physicians would completely excise a lesion that was histologically diagnosed as an incompletely removed Spitz nevus. Seventy percent of general dermatologists and 80% of pediatric dermatologists would recommend excision with a 1- to 2-mm margin of normal-appearing skin around a Spitz nevus. Nine percent of general dermatologists would recommend margins of 4 mm or more; however, all pediatric dermatologists surveyed would recommend margins less than 4 mm. Physicians were less likely to monitor patients whose Spitz nevi were completely removed. Three fourths (74%) of respondents believe Spitz nevi are entirely benign, 4% believe they are precursors to melanoma, and 22% are not sure. Seven percent of general dermatologists and 4% of pediatric dermatologists have seen metastatic melanomas arise at sites of lesions initially diagnosed histologically as Spitz nevi; 40% of pigmented-lesion clinic directors have seen such lesions.

CONCLUSIONS

We believe that the lack of consensus, both in our survey and in the medical literature, reflects to some extent the lack of certainty in the histologic differentiation of Spitz nevi from melanomas and that concern about melanoma influences management. At the pigmented-lesion clinic of the New York University Skin and Cancer Unit, because of this concern about melanoma, it is usually recommended that Spitz nevi be completely excised.

Mutations and copy number increase of HRAS in Spitz nevi with distinctive histopathological features

Spitz nevus is a benign melanocytic neoplasm that can be difficult or impossible to histologically distinguish from melanoma. We have recently described copy number increases of chromosome 11p in a subset of Spitz nevi. To study the molecular and histological features of this group, we studied 102 Spitz nevi for 11p copy number increases using fluorescence in situ hybridization (FISH) on tissue arrays. Copy number increases of at least threefold were found in 12 cases (11.8%) and involved the HRAS gene on chromosome 11p. Sequence analysis of HRAS showed frequent oncogenic mutations in cases with copy number increase (8/12 or 67%), contrasting with rare HRAS mutations in cases with normal HRAS copy numbers (1/21 or 5%, P: < 0.0001). Tumors with 11p copy number increases were larger, predominantly intradermal, had marked desmoplasia, characteristic cytological features, and had an infiltrating growth pattern. Proliferation rates in the majority of these cases were low to absent. HRAS activation by either mutation or copy number increase alone could explain several of the histological features that overlap with those of melanoma. We speculate that HRAS activation in the absence of co-operating additional genetic alterations drives the partially transformed melanocytes of these Spitz nevi into senescence or a stable growth arrest. Although there is no data suggesting that Spitz nevi with HRAS activation are at risk for progression to melanoma, future studies are warranted to assess their biological behavior more accurately.

Molecular cytogenetic analysis of Spitz nevi shows clear differences to melanoma

Spitz nevus is a benign neoplasm of melanocytes that can be difficult or impossible to distinguish from melanoma by clinical and histopathologic examination. We studied genomic DNA from 17 Spitz nevi by comparative genomic hybridization (CGH). Thirteen lesions showed no chromosomal aberrations, three cases had a gain involving the entire p-arm of chromosome 11, and one case showed a gain of chromosome 7q21-qter. Fluorescence in situ hybridization (FISH) on lesional tissue with a probe for the p-arm of chromosome 11 showed 6-10 p-arm signals per nucleus in those cases with a CGH-detected gain of chromosome 11p. One case with a normal CGH profile also showed increased copy number of 11p by FISH. Thus, the majority of Spitz nevi have a normal chromosomal complement at the level of CGH resolution; however some may contain gains, with 11p apparently being the most frequently involved location. These findings differ significantly from the previously reported changes in primary cutaneous melanoma, which show frequent deletions of chromosomes 9p (82%), 10q (63%), 6q (28%), and 8p (22%), as well as gains of chromosomes 7 (50%), 8 (34%), 6p (28%), 1q (25%) by CGH analysis. These clear differences in the location and frequencies of chromosomal aberrations in Spitz nevi and primary cutaneous melanomas could represent a basis for developing adjunctive techniques for refining accuracy in the difficult differential diagnosis of spitzoid melanocytic neoplasms.

Atypical Spitz nevi/tumors: lack of consensus for diagnosis, discrimination from melanoma, and prediction of outcome

The biological nature of Spitz nevi/tumors and their diagnostic distinction from, or relationship to, melanoma remain unresolved issues. In this report, a series of 30 melanocytic lesions removed from 28 patients, including atypical Spitz nevi/tumors and metastasizing Spitzoid tumors/melanomas, were evaluated by a panel of dermatopathologists to evaluate interobserver diagnostic concordance and to assess the prognostic power of histological criteria. For inclusion in the study, each lesion had to display some criteria for the Spitz nevus, and in addition one of the following was required: (1) definitive clinical outcome such as metastasis or death of disease, or (2) long-term follow-up if the patient remained disease free. Each lesion was reviewed independently and blinded as to the clinical data by 10 pathologists, who categorized them as (1) typical Spitz nevus/tumor, (2) atypical Spitz nevus/tumor, (3) melanoma, (4) tumor with unknown biological potential, or (5) other melanocytic lesion. There was limited discussion of criteria before the review. Evaluation of 17 Spitzoid lesions yielded no clear consensus as to diagnosis; in only one case did six or more pathologists agree on a single category, regardless of clinical outcome. Notably, however, some lesions that proved fatal were categorized by most observers as either Spitz nevi or atypical Spitz tumors. Conversely, seven or more pathologists scored 13 lesions as melanoma. These results illustrate (1) substantial diagnostic difficulties posed by many Spitz tumors, especially those with atypical features, even among experts, and (2) the lack of objective criteria for their distinction from melanoma and for gauging their malignant potential. Nevertheless, our observations do suggest that a biological relationship exists between the Spitz nevus/tumor and melanoma.

Basal cell carcinoma in a girl after cobalt irradiation to the cranium for acute lymphoblastic leukemia: case report and literature review

A 12-year-old girl had a lesion located on the upper part of the scalp that was clinically interpreted as a melanocytic nevus and corresponded histologically to a basal cell carcinoma. At age 2 years she had been diagnosed as having acute lymphoblastic leukemia L1, for which she was treated with systemic chemotherapy. She also received telecobalt therapy to the whole cranium for prophylaxis of meningeal leukosis. Having rejected other possible causes that can favor the appearance of basal cell carcinoma during childhood (basal cell nevus syndrome, nevus sebaceus, albinism, etc.), we believe that this case should be added to the five previously reported in the literature as basal cell carcinoma developing at an early age in cranial radiation portals with megavoltage radiotherapy. We draw attention to the need to explore radiated areas of skin as part of the long-term follow-up of these patients, and to the advisability of obtaining a biopsy from any persistent lesion in these areas.

"Malignant Spitz nevus" in a 2-year-old Japanese child

Smith et al. (1989) have reported a variant of Spitz's nevus with histological atypical features. Despite local lymph node metastases, further metastases were not observed. They proposed the name "malignant Spitz nevus" for this variant. A 2-year-old Japanese girl had a large nodule (27 x 17 mm) surrounded by an indurated erythema over the Achilles tendon. Histologically, it proved to be a melanocytic lesion resembling spindle cell and epithelioid cell nevus (Spitz's nevus) with unusual features; the tumor extended deep into the subcutis, and the mitotic figures deep into the tumor, together with prominent lymphatic vessel invasion by melanocytes. Thus the tumor was aptly termed "malignant Spitz nevus". Flow cytometric analysis of the DNA content revealed a diploid pattern. The child is well 5 years after a wide resection of the tumor. The diploid pattern of the DNA content as well as the good prognosis could support the idea that "malignant Spitz nevus" fits within the spectrum of Spitz's nevus.

Multiple agminated pigmented Spitz nevi (mimicking acral lentiginous malignant melanoma and dysplastic nevus) in an African-American girl

BACKGROUND

Reed's nevi are distinguished from Sptiz tumors by their significant melanogenesis and growth pattern. They may be confused with melanoma on clinical and histologic grounds.

CASE REPORT

An unusual case in which multiple agminated Reed's nevi mimicked acral lentiginous malignant melanoma in an African-American girl is presented. A critical review of the literature is presented to assist in the diagnosis.

CONCLUSIONS

Awareness of this entity and of its possible clinical presentations and judicious application of conventional hematoxylin-eosin microscopic criteria remain the most useful methods to bring the correct diagnosis in most instances. Mutilating or excessive surgery may be avoided for most cases of pigmented spindle and epithelioid cell nevus.

Spitz nevi

The Spitz nevus has long been defined as a benign melanocytic lesion that shares many histologic features with malignant melanoma. Despite the diagnostic criteria established for these two entities, their histologic similarities continue to make their distinction somewhat difficult. Uncertainties also exist with regard to the natural history of the Spitz nevus; the true pattern of this lesion's biologic behavior remains elusive. As a result, controversies exist with respect to appropriate therapy. To examine these controversies, the epidemiology, clinical features, and histopathology of Spitz nevi, as well as the role of recent molecular and immunohistochemical diagnostic studies, are discussed. However, the primary focus of this article is the natural course, prognosis, and treatment of the Spitz nevus. A review of 716 cases of Spitz nevi, compiled from 13 papers published from 1948 to 1990, is presented. After analyzing this and other available data, we propose that at this time Spitz nevi and malignant melanoma cannot easily be categorized as distinct entities and that perhaps they actually exist along one continuum of disease. Because of this uncertainty and the difficulties in differentiating these two lesions, we recommend that treatment include complete excision of all Spitz nevi followed by reexcision of positive margins if present.

Second neoplasms after acute lymphoblastic leukemia in childhood

BACKGROUND

Effective forms of treatment for acute lymphoblastic leukemia (ALL) in childhood now result in survival rates above 70 percent at five years, but the treatments are potentially carcinogenic. To determine the magnitude of this risk and identify possible risk factors for the development of second neoplasms, we studied a large cohort of children treated for ALL. METHODS AND RESULTS. We undertook a retrospective cohort study of 9720 children who had been given a diagnosis of ALL between June 1972 and August 1988 and had been treated according to the therapeutic protocols of the Children's Cancer Study Group. The median follow-up was 4.7 years (range, 2 months to 16 years). We found that 43 second neoplasms occurred among the children in the cohort, including 24 neoplasms of the central nervous system, 10 new leukemias and lymphomas, and 9 other neoplasms. This represented a 7-fold excess of all cancers and a 22-fold excess of neoplasms of the central nervous system. The estimated cumulative proportion of children in whom a second neoplasm developed was 2.53 percent 15 years after diagnosis (95 percent confidence limits, 1.74 percent and 3.38 percent). An even higher risk, particularly of central nervous system tumors, was evident in children five years of age or less at the time of the diagnosis of ALL (P = 0.012). All central nervous system neoplasms developed in children who had previously undergone irradiation. There was no association with exposure to cyclophosphamide or anthracyclines.

CONCLUSIONS

There is a substantial excess of second neoplasms, especially of the central nervous system, among children treated for ALL. Children five years old or younger and those receiving radiation are at higher risk, especially for second tumors arising in the central nervous system.

Important melanocytic lesions in childhood and adolescence

Melanocytic nevi are common in children and adolescents, and the preponderance of these lesions are benign. Congenital melanocytic nevi, dysplastic nevi, and large numbers of common acquired nevi, however, may indicate an increased risk of malignant melanoma. With the exception, possibly, of giant congenital nevi, melanoma associated with these lesions generally occurs in adulthood. Nonetheless, some patients can be identified as being at increased risk for the development of melanoma during childhood. The poor prognosis associated with advanced melanoma and the curability of early lesions underscore the importance of prompt recognition of melanoma when it does occur in children. Furthermore, physicians who care for children are in a key position to decrease risk of melanoma throughout the lifespan by encouraging avoidance of excessive sun exposure during childhood.

Childhood melanoma

In melanoma patients, the prognostic value of tumor depth, Clark's level, the presence of ulceration, and regional involvement have not been clearly documented in the pediatric population. This report correlates these factors in a population-based study of patients under the age of 20 years. Of the initial 35 melanoma patients registered in southern Alberta with the Alberta Cancer Board, 14 were found on review to have a diagnosis other than melanoma. In the remaining 21 cases the diagnosis of melanoma was confirmed. There was a suggestion that patients with deeper lesions had a worse prognosis, but this was statistically confirmed only using Clark's levels. The children were then compared with all melanoma patients diagnosed in southern Alberta over the same time period. There was no difference in tumor depth, Clark's level, ulceration, regional involvement, or survival between these two groups. The natural history in children appears to be similar to that of the adult population, contrary to previous reports suggesting a markedly worse prognosis.

Melanoma in children

Four cases of malignant melanoma in children younger than 17 years of age are presented. Several preexisting conditions increase the risk of development of melanoma during childhood. These include giant congenital melanocytic nevi, the familial dysplastic nevus syndrome, and xeroderma pigmentosum. The role of small congenital lesions and sporadic dysplastic nevi in the development of melanoma in children is less clear. The signs and symptoms associated with melanoma in children are similar to those in adults, as are the histopathologic features, biologic behavior, and treatment of this tumor. The inadequacy of available therapy for metastatic melanoma underscores the necessity for the early diagnosis and prompt surgical treatment of melanomas in children.

Multiple agminate Spitz nevi

A five-year-old boy had multiple agminate Spitz nevi arising in an area of hyperpigmentation that developed concurrently with the nevi. Multiple Spitz nevi occurring in a single group are rare, and their presence on a hyperpigmented background is extremely uncommon. Very few such cases have been described, and all of those lesions arose on a congenital hyperpigmented patch. In contrast, the nevi in our patient appeared to arise on an acquired hyperpigmented patch that was not present at birth, and histologically did not demonstrate features of a congenital nevus. Accurate diagnosis is necessary to avoid unnecessary radical therapy.