CUTANEOUS TUMORS OF CHILDREN

Nevi are the most common tumors of childhood. Pigmented nevi are classified into blue nevi, intraepidermal nevi, junction nevi, intradermal nevi (or common mole) and combination types. Cutaneous malignant disease in children is rare. Malignant melanoma is rare before puberty. Wholesale removal of benign pigmented nevi in children should be condemned. However, junction nevi located on the palms, soles, genitalia or waistline—that is, in areas subject to frequent trauma—should be excised.Hemangiomas in infants are the most common tumors for which advice is sought. Not all hemangiomas regress spontaneously, and on occasion the persistence or progression of such a lesion may bring about life-long unsightly deformities. Therapy for this type of tumor is simple when given early in life. Hemangiomas involving the ears, nose, lips or eyelids should be treated at once, preferably within a month of the time they appear.     

Hemangiomas; histologic structure,and treatment

Hemangiomas are considered tumors originating in blood vessels and are classified as ectatic and hyperplastic. Controversy regarding active therapy occurs in the case of strawberry hemangiomas which are hyperplastic capillary hemangiomas. Although they may clear up spontaneously, on rare occasions they may predispose to grave sequelae. Port-wine stain hemangiomas should never be treated with x-ray or radium.     

HEMANGIOMAS—Histologic Structure,and Treatment

Hemangiomas are considered tumors originating in blood vessels and are classified as ectatic and hyperplastic. Controversy regarding active therapy occurs in the case of strawberry hemangiomas which are hyperplastic capillary hemangiomas. Although they may clear up spontaneously, on rare occasions they may predispose to grave sequelae. Port-wine stain hemangiomas should never be treated with x-ray or radium.     

326 例眼睑肿物的临床病理分析

目的:总结眼睑肿物的临床病理类型及特点。方法:收集2000年1月至2011年6月到青岛大学医学院附属医院眼科住院部行手术治疗眼睑肿物患者326例的临床病理资料进行分析。结果:在326例眼睑肿物中,良性肿瘤156例,占47.9%,恶性肿瘤63例,占19.3%;炎性改变98例,占30.1%。良性肿瘤的前五位分别是色素痣、乳头状瘤、囊肿、疣、血管瘤;恶性肿瘤前三位分别是基底细胞癌、睑板腺癌、鳞状细胞癌;炎性改变以炎性肉芽肿最常见。儿童多发的眼睑肿物为皮样瘤、钙化上皮瘤。结论:眼睑病变以良性肿瘤多见,其次为炎性改变。良性肿瘤中以色素痣、乳头状瘤和囊肿多见;恶性肿瘤最常见的为基底细胞癌,儿童眼睑肿瘤以皮样瘤最多见。     

Surgical management of parotid hemangioma

Hemangiomas represent one of the most common childhood neoplasms. They are often managed conservatively, requiring numerous years for spontaneous involution. No effective medical treatment has been reported for children with large, deforming hemangiomas of the parotid gland and overlying cheek. The authors retrospectively studied 17 children who underwent surgical resection of parotid hemangiomas at Childrens Hospital Los Angeles from 1997 to 2003. All 17 patients had improvements in facial asymmetry and deformity. There were no major complications. Minor complications included hematoma (11.8 percent), transient facial nerve palsy (11.8 percent), and blood transfusion (5.9 percent). All operations were performed on an outpatient basis. Surgical resection of parotid hemangiomas provides an aesthetic benefit to young children with low associated morbidity. Early resection by an experienced surgeon should be considered as a treatment option for these disfiguring lesions.     

Giant congenital melanocytic nevi: the significance of neurocutaneous melanosis in neurologically asymptomatic children

Patients with a giant congenital melanocytic nevus can develop melanotic tumors characterized by central nervous system involvement, termed leptomeningeal melanocytosis or neurocutaneous melanosis. Although symptomatic neurocutaneous melanosis is rare, we previously reported distinct magnetic resonance (MR) findings of T1 shortening, strongly suggestive of neurocutaneous melanosis, in 30 percent (6 of 20) of children with giant congenital melanocytic nevi who presented initially without neurological symptoms. The purpose of this study was to determine the incidence of neurocutaneous melanosis in high-risk patients and its long-term clinical significance.Magnetic resonance imaging was recommended for all 46 patients with "at-risk" giant congenital melanocytic nevi involving the skin overlying the dorsal spine or scalp. The clinical histories and follow-up of these patients were evaluated by retrospective chart review. Forty-two underwent MR imaging of the brain and 11 underwent additional MR scanning of the spinal cord. Abnormalities were identified in 14 of 43 MR studies, and 23 percent (n = 10) had T1 shortening indicative of melanotic rests within the brain or meninges. None had associated masses or leptomeningeal thickening. The most common areas of involvement in these 10 included the amygdala (n = 8), cerebellum (n = 5), and pons (n = 3). In the group of 11 patients with spinal MR scans, a tethered spinal cord was demonstrated in one. Additional abnormalities were detected by MR scanning, including a middle cranial fossa arachnoid cyst, a Chiari type I malformation, and a crescentic enhancement that subsequently resolved. Clinical follow-up averaging 5 years (range, 2 to 8 years) revealed that only one of the 46 patients evaluated developed neurological symptoms, manifested as developmental delay, hypotonia, and questionable seizures but no other signs of neurocutaneous melanosis. No patient has developed a cutaneous or central nervous system melanoma. Magnetic resonance findings of neurocutaneous melanosis are relatively common, even in asymptomatic children with giant congenital melanocytic nevi. Although these findings suggest an increased lifetime risk of central nervous system melanoma, they do not signify the eventual development of symptomatic neurocutaneous melanosis during childhood.     

Sensitivity and positive predictive values of presurgical clinical diagnosis of excised benign and malignant skin tumors: a prospective study of 835 lesions in 778 patients.

This article reports on the sensitivity and positive predictive value of clinical diagnosis of benign and malignant skin tumors by expert plastic surgeons in an Israeli clinic. Most published reports have focused on the sensitivity of clinicians' diagnoses, a general measure of the physician's skill that does not predict the rate of accuracy of a physician's diagnoses. Our study of 835 lesions in 778 patients, one of the largest Israeli series, assesses the clinical diagnosis of malignant and benign skin tumors and is one of the few that provide information on the positive predictive value, the measure that is of interest to both physicians and patients. The majority of tumors were benign (56.8 percent), 31.6 percent were malignant, and 11.6 percent were premalignant. Among the 474 benign lesions, 46 percent were nevi. The most common nevi subclass was compound nevi (53 percent), 9 percent of the nevi were dysplastic, and 5 percent were blue nevi. The most common malignant tumor was basal cell carcinoma, accounting for 78 percent of malignant tumors.Although sensitivity for clinical diagnosis of malignancy was 91.3 percent, the positive predictive value for clinical diagnosis of malignancy was 71.3 percent. The sensitivity rate for clinically diagnosing premalignant tumors was 42.3 percent, whereas the positive predictive value for these diagnoses was higher (64.1 percent). The sensitivity rate for diagnosis of all benign lesions was 85.9 percent, and the positive predictive value was 94.2 percent. The sensitivity rate for diagnosis of all nevi was 87.6 percent, and the positive predictive value was 85.7 percent: i.e., only seven of the 218 pathologically proven diagnoses of nevi (3.2 percent) were falsely diagnosed as malignant lesions. Even more interestingly, five of the 223 clinical diagnoses of nevi (2.2 percent) were pathologically proven to be malignant melanomas, and seven were found to be premalignant lesions (3.1 percent). It was concluded that publications which report only on the sensitivity neglect to provide information of interest regarding the positive predictive value. Often, positive predictive value is qualitatively different from the sensitivity, and thus relying only on the sensitivity may lead to incorrect evaluation of a clinical judgment, which may result in erroneous surgical decisions.     

EARLY DIAGNOSIS OF MALIGNANT MELANOMA OF THE SKIN

About five per cent of all malignant lesions of the skin are malignant melanomas. The poor prognosis associated with this malignant lesion emphasizes the importance of early diagnosis. A large proportion of malignant melanomas arise in preexisting lesions such as junction nevi, precancerous melanoses and, much more rarely, blue nevi. Early malignant changes in these precursor lesions include increasing pigmentation, enlargement, thickening, crusting, bleeding, ulceration, tumor formation, and development of satellite lesions.Many pigmented, and some non-pigmented, lesions of the skin must be differentiated from malignant melanoma. Since even with radical surgical treatment the prognosis of malignant melanoma is poor, junction nevi which are subject to continual trauma or have signs of probable malignant degeneration should be prophylactically excised.     

儿童胃肠间质瘤治疗进展

胃肠道间质瘤(Gastrointestinal stromal tumors, GIST)是最常见的间叶源性肿瘤。最新统计结果显示,其全球发病率约5~19/106。成人患者临床表现常无特异性,患者多有腹痛、血便、腹胀等症状。GIST主要发生在中老年群体,在儿科极为罕见,因此儿童患者经常被漏诊或误诊。随着近年来基因检测的广泛应用,以及有关儿童GIST研究的深入,发现它代表着一个不同于成人GIST的临床疾病。成人GIST当前主要治疗方式以手术为主,同时根据患者病情应用靶向药物辅助治疗。然而对于儿科患者,一些用于成人肿瘤的治疗方案难以达到理想的治疗效果,甚至会造成不良后果。儿童胃肠道间质瘤的独特生物学特性,决定了它需要独特的治疗方案,以达到最佳的临床疗效。本综述旨在研讨最新文献,提供不同的儿童胃肠道间质瘤的治疗方式。     

"Halo nevi" and UV radiation

Halo nevi, also termed Sutton nevi, are defined as benign melanocytic nevi that are surrounded by an area of depigmentation resembling a halo. Halo nevi are common in children and young adults, with a mean age at onset of 15 years. The incidence in the population is estimated to be approximately 1%. Affected individuals frequently have multiple lesions which are usually localized on the back. A familial tendency for halo nevi has been reported. The etiology of halo nevi is unknown. It is an autoimmune response and T lymphocytes are considered to play a key role in the progressive destruction of nevus cells. Halo nevi may be associated with autoimmune disorders such as vitiligo, Hashimoto thyroiditis, alopecia areata, celiac disease, atopic dermatitis and others. It has been proved that halo nevi are detected after an intense sun exposure especially after sunburns. The etiology of halo nevi, association with malignant melanoma and the role of sun exposure in the development of halo nevi are discussed.     

Ophthalmic issues in hemangiomas of infancy

Hemangiomas are the most common benign tumor of infancy. Although most hemangiomas remain asymptomatic, certain hemangiomas can cause significant morbidity and require treatment. Periocular hemangiomas require close observation and early therapy for those lesions with potential for visual impairment. Hemangiomas typically cause visual morbidity by induction of amblyopia, strabismus, significant refractive error or optic nerve compromise. Diagnosis is typically straightforward but occasionally other entities may cause diagnostic confusion and radiologic evaluation can be helpful. This is particularly important if the hemangioma is one component of the PHACES syndrome. Therapeutic options which may be useful include steroids (oral, intralesional or topical), interferon alpha (usually reserved for life- or sight-threatening lesions due to serious potential side effects), laser, embolization and surgery. Ophthalmic treatment using patching, atropine, glasses and stabismus surgery may be necessary.     

Acquired melanocytic nevi as risk factor for melanoma development. A comprehensive review of epidemiological data

Acquired melanocytic nevi (MN) in Caucasian populations are important markers for the risk of melanoma development. The total number of MN on the whole body is the most important independent risk factor for melanoma and the risk of melanoma development increases almost linearly with rising numbers of MN. Additionally, the presence of atypical MN and of actinic lentigines are likewise independent risk factors for melanoma. Atypical mole syndrome should be defined by the presence of many acquired MN and a threshold number of atypical MN. Acquired MN develops mainly during childhood and adolescence in the first two decades of life. The number of acquired nevi seems to be related to hereditary factors and nevus-prone families exist. The amount of sun exposure is the most important environmental risk factor for nevus development, particularly in early childhood. Interestingly, sunburns may play a role in nevus development, but seem not to be required, and even moderate sun exposure promotes the process. Therefore, preventive measures for nevus and melanoma development should target young children and adolescents.     

Giant congenital nevi: a 20-year experience and an algorithm for their management.

A variety of treatment options exists for the management of giant congenital nevi. Confusion over appropriate management is compounded because not all giant congenital nevi are pigmented, and malignant potential varies between different types. The present study sought to define factors in the presentation of giant congenital nevi that could provide an algorithm for their management, with respect to both the extent of resection and subsequent reconstructive options.A retrospective review of all patients who presented with a congenital nevus of 20 cm2 or greater since 1980 was performed, distinguishing among nevi involving the head and neck, the torso, and the extremities. Sixty-one patients with giant congenital nevi were evaluated (newborn to age 16 years), of which 60 nevi in 55 patients have been operated on.Giant congenital nevi having malignant potential were pigmented nevi (53 patients) and nevus sebaceus (four patients). Those not having malignant potential were verrucous epidermal nevi (three patients) and a woolly hair nevus (one patient). Of the 60 giant congenital nevi operated on, expanded flaps were used in 25, expanded full-thickness skin grafts were used in 10, split-thickness or nonexpanded full-thickness skin grafts were used in 13, and serial excision was used in 30. After 1989, operations tended to use multimodality treatment plans, with an increased use of expanded full-thickness grafts and immediate serial tissue expansion. The use of serial excision, particularly in the extremities, also increased after 1989. Serial excision was the treatment of choice when it could be completed in two procedures or less, which occurred in more than 80 percent of cases using serial excision alone. Expanded flaps were the most common mode of reconstruction in the head and neck region and were used in 49 percent of these procedures. Serial excision was the most common form of treatment in the extremities, used in 50 percent of procedures. Tissue expansion in the extremities was infrequently used to provide an expanded flap (8 percent of procedures), whereas it was frequently used to provide expanded full-thickness skin grafts harvested from the torso (used in 31 percent of procedures).On the basis of these data, algorithms for the extent of resection and subsequent reconstructive options for giant congenital nevi were developed. Their management should be formulated relative to pigmentation, malignant potential, and anatomic location of the respective lesions.     

Identifying potential regulators of infantile hemangioma progression through large-scale expression analysis: a possible role for the immune system and indoleamine 2,3 dioxygenase (IDO) during involution

Hemangiomas are benign endothelial tumors. Often referred to as hemangiomas of infancy (HOI), these tumors are the most common tumor of infancy. Most of these lesions proliferate rapidly in the first months of life, and subsequently slowly involute during early childhood without significant complications. However, they often develop on the head or neck, and may pose a significant cosmetic concern for families. In addition, a fraction of these tumors can grow explosively and ulcerate, bleed, or obstruct vision or airway structures. Current treatments for these tumors are associated with significant side effects, and our knowledge of the biology of hemangiomas is limited. The natural evolution of these lesions creates a unique opportunity to study the changes in gene expression that occur as the endothelium of these tumors proliferates and then subsequently regresses. Such information may also increase our understanding of the basic principals of angiogenesis in normal and abnormal tissue. We have performed large-scale genomic analysis of hemangioma gene expression using DNA microarrays. We recently identified insulin-like growth factor 2 as a potentially important regulator of hemangioma growth using this approach. However, little is known about the mechanisms involved in hemangioma involution. Here we explore the idea that hemangioma involution might be an immune-mediated process and present data to support this concept. We also demonstrate that proliferating hemangiomas express indoleamine 2,3 dioxygenase (IDO) and discuss a possible mechanism that accounts for the often slow regression of these lesions.     

Salivary Gland Tumors and Sialadenitis in Children—Experience at Childrens Hospital of Los Angeles

Parotitis, hemangio-endothelioma and mixed tumors are the most common salivary gland lesions in the pediatric age group. Carcinoma and sarcoma are uncommon. Rapid growth of a tumor and pain suggest malignant change.A conservative non-operative approach is stressed for most cases of chronic parotitis. Scout x-ray films and sialangiographic examination are useful in differentiating an inflammatory lesion from a neoplastic growth. Total parotidectomy is advised if operation is indicated.A case of spontaneous resolution of a hemangioma of the parotid gland is presented. A less aggressive temporizing plan should be considered with these lesions, as the risk of seventh nerve injury in children is considerable.The treatment of choice for a non-inflammatory tumor is surgical excision, for most parotid tumors are radioresistant. Small masses should be completely excised for pathological evaluation. Incisional biopsy may occasionally be indicated in the case of a large diffuse lesion, for it may be inflammatory and total excision unnecessary. Most patients with chronic parotitis came to medical attention because of a non-tender asymptomatic parotid lump or diffuse swelling.     

Hemangiomas - current therapeutic strategies

Hemangiomas are benign neoplasms of the vasculature frequently encountered in children. Several studies have shown that these tumors are characterized by excessive angiogenesis. Although benign, the lesions can present with complications, and may thus require treatment. There are multiple therapeutic options available for patients with problematic or life threatening hemangiomas, some of which have serious side effects. Randomized clinical trials and evidence-based studies on the efficacy of these treatments is still lacking. The recognition that excessive angiogenesis underlies hemangiogenesis offers an opportunity for the development of safer therapeutic strategies that are based on the inhibition of angiogenesis. We review medical therapies currently employed in the management of hemangiomas and the role of angiogenesis inhibition in hemangioma therapy.     

Genetics of melanocytic nevi

Melanocytic nevi are a benign clonal proliferation of cells expressing the melanocytic phenotype, with heterogeneous clinical and molecular characteristics. In this review, we discuss the genetics of nevi by salient nevi subtypes: congenital melanocytic nevi, acquired melanocytic nevi, blue nevi, and Spitz nevi. While the molecular etiology of nevi has been less thoroughly studied than melanoma, it is clear that nevi and melanoma share common driver mutations. Acquired melanocytic nevi harbor oncogenic mutations in BRAF, which is the predominant oncogene associated with melanoma. Congenital melanocytic nevi and blue nevi frequently harbor NRAS mutations and GNAQ mutations, respectively, while Spitz and atypical Spitz tumors often exhibit HRAS and kinase rearrangements. These initial ‘driver’ mutations are thought to trigger the establishment of benign nevi. After this initial phase of the cell proliferation, a senescence program is executed, causing termination of nevi growth. Only upon the emergence of additional tumorigenic alterations, which may provide an escape from oncogene‐induced senescence, can malignant progression occur. Here, we review the current literature on the pathobiology and genetics of nevi in the hope that additional studies of nevi promise to inform our understanding of the transition from benign neoplasm to malignancy.     

The dysplastic nevus: recognition and management

The recognition of atypical or dysplastic nevomelanocytic nevi potentially provides clinicians with another means of identifying individuals at increased risk for cutaneous malignant melanoma. However, a great deal of controversy still surrounds these lesions, their significance, and the clinical and histologic criteria needed for their diagnosis at present. In general, dysplastic nevi tend to be asymmetrical and larger (greater than 5 mm) than ordinary acquired nevi, have a macular component, irregular and ill-defined borders, and haphazard (variegate) coloration. A clinical diagnosis of dysplastic nevi must be confirmed by histopathology, since not all clinically atypical nevi are dysplastic. While precise histopathologic criteria for dysplastic nevi are lacking, most authorities agree that an abnormal nevomelanocytic proliferative pattern as manifested by increased numbers of basilar melanocytes and/or abnormal junctional nevomelanocytic nesting in the setting of lentiginous epidermal hyperplasia, variable degrees of nevomelanocytic nuclear atypia, and a lymphocytic host response are consistent with a histologic diagnosis of dysplastic nevi. Current data for individuals with dysplastic nevi and a family history of cutaneous malignant melanoma (at least two family members with cutaneous malignant melanoma) indicate a relative risk for cutaneous malignant melanoma about 148 times that of the general population. In comparison, cutaneous malignant melanoma risk seems lower for individuals with familial dysplastic nevi (but without familial cutaneous malignant melanoma) and "sporadic" dysplastic nevi. With respect to progression to melanoma, probably the vast majority of dysplastic nevi remain stable or possibly regress. Management of individuals with histologically confirmed dysplastic nevi involves periodic skin examinations. Regional overview and life-size photography are helpful in following these patients. Patients should also be instructed in the examination of their own skin. While a definite relationship between sun exposure and dysplastic nevi remains unproved, the use of sunscreens and avoidance of unnecessary sun exposure are advised. Examination of family members for atypical melanocytic lesions is also recommended.     

Black lesions of the skin

Benign melanocytic lesions include lentigo, ephelid (freckle), pigmented nevus, sacral spot, blue nevus, and combined nevus and blue nevus. Malignant melanocytic lesions are melanomas, which arise from melanocytes at the epidermodermal junction, or, rarely, from blue nevi. They usually originate in brown plaques known as lentigo maligna, in pigmented nevi, or in normal skin. Melanoma is diagnosed clinically in less than 50 per cent of instances. Biopsy is therefore of great importance, since practically all melanoma can be cured by adequate early resection.     

The molecular pathogenesis of childhood adrenocortical tumors.

Adrenocortical tumors in children and adolescents are rare events. However, the high incidence of adrenocortical tumors in children from the Southern region of Brazil is particularly remarkable, since it has been estimated to be approximately 10-15 times greater than the worldwide incidence. To date, there are no histological or molecular markers that can reliably distinguish benign from malignant adrenocortical tumors. The study of rare genetic syndromes associated with adrenocortical tumors has greatly contributed to the elucidation of sporadic adrenocortical tumorigenesis. Recently, considerable advances toward understanding the molecular mechanisms of adrenocortical tumorigenesis in Brazilian children and adolescents with sporadic adrenocortical tumors have been made. Some of the molecular aspects of sporadic adrenocortical tumors arising in children and adolescents are reviewed here.