Actinic keratosis: precancer, squamous cell carcinoma, or marker of field cancerization?

The early detection, recognition, and progression of the actinic keratosis (AK) and its relationship with squamous cell carcinoma have long been an area of debate. Recent advancements in medicine have examined the role of field cancerization in a variety of tumors. The role of AK as a marker for field cancerization will be here discussed.

Dense inflammation does not mask residual primary basal cell carcinoma during Mohs micrographic surgery.

BACKGROUND: Areas of dense inflammation are commonly removed during Mohs micrographic surgery for basal cell carcinoma because of the concern that they may mask areas of tumor. OBJECTIVE: Our purpose was to determine whether inflammation masks tumor during Mohs surgery for primary basal cell carcinoma. METHODS: Twenty-five consecutive cases of primary basal cell carcinoma with areas of dense inflammation encountered during Mohs surgery were sectioned and stained with hematoxylin and eosin and Ber-EP4. RESULTS: In no cases did the dense inflammation mask residual tumor. CONCLUSION: Dense inflammation does not mask primary basal cell carcinoma during Mohs surgery and should be carefully evaluated before additional surgery is performed.

Poromas of the head and neck.

BACKGROUND: The "eccrine" poroma is a benign neoplasm previously thought to originate from the eccrine sweat gland. Early studies suggested that these were primarily lesions of the hairless acral surfaces. OBJECTIVE: This article reports the clinical and histologic findings of 10 cases of poroma of the head and neck area. METHODS: The clinical and histologic findings of 10 cases of poroma of the head and neck area are compared with 10 poromas occurring on the extremities. RESULTS: Some poromas demonstrated evidence for apocrine origin. Unlike poromas found on the extremities, head and neck poromas were usually asymptomatic and were never correctly diagnosed clinically. Although 9 of 10 poromas on the extremities occurred in male patients, the head and neck poromas showed no gender predilection. CONCLUSION: Clinicians should be aware that poromas can occur in the head and neck area and may be of apocrine origin.

Spiny keratoderma.

Spiny keratoderma is a descriptive term used to encompass a variety of unusual, disparate keratodermas. Spiny keratoderma has been associated with lipid abnormalities and has been limited to the palms and soles in some individuals. We describe an acquired case of spiny keratoderma in which an adult woman developed filiform lesions predominating on the trunk and proximal extremities. Treatment with topical emollients and keratolytic agents was unsuccessful, but topical tazarotene led to long periods of resolution. She has had no other associated abnormalities. The clinical features and differential diagnosis of spiny keratoderma are reviewed.

Inexpensive digital photography in clinical dermatology and dermatologic surgery.

Digital photography can be used to follow clinical improvement in a variety of dermatoses, document pre and postoperative results, and document histologic findings from skin biopsies. Images may be printed as part of text documents and can be filed in conventional medical charts. Images can be transmitted via electronic mail rapidly and to any location. We have found digital photography to be relatively inexpensive and a powerful tool to enhance dermatologic practice.

Pemphigus foliaceus successfully treated with mycophenolate mofetil as a steroid-sparing agent.

Pemphigus foliaceus is an autoimmune blistering disease of unknown origin with antibodies produced against desmoglein 1, an adhesive protein found in the desmosomal cell junction in the suprabasal layers of the epidermis. The disease is primarily treated with corticosteroids and corticosteroid-sparing immunosuppressive agents. We report a case of pemphigus foliaceus successfully treated with mycophenolate mofetil. It remains to be seen whether this agent has a significant effect on the course of the disease and remission induction.

An unusually aggressive trichoblastoma.

Trichogenic tumors are neoplasms of the hair germ cell that usually exhibit benign behavior. We describe a case of a large invasive trichoblastoma requiring Mohs micrographic surgery for its removal. Immunohistochemical studies performed demonstrate overlapping features of this trichogenic tumor with basal cell carcinoma.

The spectrum of epidermal nevi: a case of verrucous epidermal nevus contiguous with nevus sebaceus.

During the normal development of skin, pluripotential cells give rise to keratinocytes, sebaceous glands, hair follicles, apocrine glands, and eccrine glands. In epidermal nevi, these components emerge in an abnormal mixture within a circumscribed site. Many authors have categorized epidermal nevi based on their predominant component; however, there is often notable overlap that occurs within a single area or within contiguous areas. We report a verrucous epidermal nevus contiguous to a nevus sebaceus of Jadassohn. The categories of epidermal nevi are somewhat artificial. Our case supports the view that epidermal nevi have a spectrum of manifestations, including verrucous epidermal nevi and nevus sebaceus of Jadassohn.

Rapidly growing squamous cell carcinoma.

BACKGROUND: Squamous cell carcinoma (SCC) may present with a history of rapid growth. Although multiple subtypes have been described regarding histologic characteristics and etiology, the subset of rapidly growing squamous cell carcinomas (RGSCC) has not been described. OBJECTIVE: To evaluate and describe the clinical and histologic characteristics of squamous cell carcinomas that grow rapidly. METHODS: Recorded clinical data and biopsies of 26 lesions with a history of rapid growth and histologically diagnosed as SCC were reviewed. RESULTS: Rapidly growing SCC occurred most commonly on the head and neck, followed by hands and extremities, and had an average duration of 7 weeks before diagnosis. The average size of the lesions was 1.29 cm and nearly 20% occurred in immunosuppressed patients. CONCLUSIONS: Some SCCs may grow rapidly. The reason for the rapid growth is not clear and several hypotheses are discussed including immunosuppression and viral etiology. These lesions should be treated aggressively as their behaviour and prognosis are not yet well described.

Chemotherapy-induced inflammation in seborrheic keratoses mimicking disseminated herpes zoster.

We report a rare instance of chemotherapy-induced seborrheic keratoses of Leser-Trelat in a patient with acute leukemia. In addition, this is the first known case to mimic disseminated herpes zoster.

Cytokeratin 20: a marker for diagnosing Merkel cell carcinoma.

Merkel cell carcinoma is an aggressive cutaneous neoplasm that is often difficult to diagnose because of its histologic and immunohistochemical similarity to metastatic oat cell carcinomas and other cutaneous neoplasms. Our purpose was to determine the utility of immunoperoxidase staining of cytokeratin 20 (CK 20), a newly discovered intermediate filament protein, in Merkel cell carcinomas and other cutaneous tumors. Sixty-one tumors were sectioned and stained with antibodies directed at CK 20. The staining of Merkel cell carcinomas was compared with metastatic oat cell carcinomas, lymphomas, squamous cell carcinomas, basal cell carcinomas, melanomas, metastatic carcinoids, spiradenomas, eccrine carcinomas, adenoidcystic carcinoma, sebaceous carcinomas, hidradenomas, sebaceous epitheliomas, trichoblastomas, mixed tumors, and metastatic adenocarcinomas. Nine of 10 Merkel cell carcinomas stained with antibody to CK 20. Two metastatic carcinomas to the skin were also positive. One hidradenoma and one squamous carcinoma exhibited focal staining, but were otherwise negative. All other tumors were nonstaining. Cytokeratin 20 is a sensitive and specific marker for Merkel cell carcinoma and is helpful in distinguishing between Merkel cell carcinoma and other malignant and benign neoplasms.

Diagnosing basal cell carcinoma by dermatoscopy.

BACKGROUND: Dermatoscopy (DS) has been used primarily to evaluate pigmented skin lesions. Little information is available on DS findings of basal cell carcinoma (BCC). Dermatoscopy is a noninvasive technique that allows visualization of cutaneous features from the skin surface to the papillary dermis. Basal cell carcinoma, the most common cutaneous malignancy, is traditionally diagnosed clinically and confirmed with biopsy. OBJECTIVE: To determine the dermatoscopic features of nonpigmented basal cell carcinomas. METHODS: The dermatoscopic findings of 27 lesions that clinically were suspicious for BCC were analyzed. RESULTS: Of these 27 clinically suspect lesions, the biopsies revealed BCC in 20 specimens and squamous cell carcinoma (SCC) in two specimens. Twenty of these 22 specimens had dermatoscopic findings of BCC: diffusely distributed, branching blood vessels, asymmetric, and narrow blood vessels distributed deeper in the dermis, or a milky-red corona with superficial wide blood vessels. One nodular BCC in our study showed no distinct findings. CONCLUSIONS: Many BCCs have characteristic DS findings; however, dermatoscopic examination of some tumours will not demonstrate any known characteristic findings. As such, the DS criteria we propose for BCC are best utilized as an adjunctive study of clinical impressions. Biopsy remains the definitive diagnostic tool.

Acute hemorrhagic edema of infancy: Finkelstein's disease.

Acute hemorrhagic edema of infancy (AHEI) is a benign form of leukocytoclastic vasculitis limited to the skin, which occurs in children younger than 2 years of age. The abrupt onset of fever, peripheral edema, and purpuric targetoid plaques in an infant may be confused with other dermatoses such as Henoch-Schönlein purpura, Sweet's syndrome, erythema multiforme, or septic vasculitis. Laboratory studies of patients with AHEI typically show normal results and the disorder follows a benign course with spontaneous resolution occurring in 1 to 3 weeks. We present a case of AHEI occurring in a 7-month-old boy and review the characteristic features of this acute dermatosis.

Sweet's syndrome without granulocytosis.

BACKGROUND: Sweet's syndrome (SS), acute febrile neutrophilic dermatosis, has been linked to hematologic malignancies and presents with characteristic edematous dermal plaques. Peripheral blood neutrophilia is frequently seen in association with SS and is one of the diagnostic criteria. OBJECTIVE: To report the clinical, laboratory, and hematologic data of four patients with myeloid leukemia who developed SS after chemotherapy. Three of these patients were neutropenic. METHODS: A retrospective study of four patients with SS and hematologic malignancies was undertaken. Three patients had de novo acute myelogenous leukemia and one was in the acute blast crisis of chronic myelogenous leukemia. RESULTS: Sweet's syndrome was not originally suspected in these patients because of the low peripheral white blood cell counts caused by chemotherapy. All of the patients presented with fevers, arthralgias, and an eruption. They had been treated with antibiotics because of a presumed infection. Once the correct diagnosis was made and oral prednisolone was started, a rapid response followed. CONCLUSIONS: Sweet's syndrome should be considered in the differential diagnosis when acute myeloid leukemic patients develop skin lesions and unexplained fevers regardless of the peripheral blood counts.

Localized limb cutaneous metastases.

Cutaneous metastatic disease may be evident in a variety of forms and locations. Anatomically, it may on occasion be confined as localized limb metastases. We report on two patients with localized limb metastases, one from melanoma and the other from Merkel cell carcinoma. Patients with localized limb metastasis have a poor prognosis; however, treatment options not available for generalized cutaneous metastatic disease, such as amputation or isolated limb perfusion with chemotherapeutic agents, can be at times be beneficially employed.

Utility of deeper sections and special stains for dermatopathology specimens.

Special (non-hematoxylin and eosin) stains and deeper sections are routinely used in dermathopathology, although their utility has not been well established. All cases requiring special stains or deeper sections over a three-month period were reviewed to see how often these additional studies contributed to accurate diagnosis. In our series, deeper sections provided diagnostic information to the pathologist in 37.3% [95% confidence interval (CI) 28-46%] of the cases in which they were performed. Deeper sections are more likely to provide a more accurate diagnosis (23.6%, 95% CI 16-32%) rather than establish a new diagnosis not seen on the original sections (13.6%, 95% CI 7-20%). Their use is especially helpful in assessing the presence or absence of cutaneous malignancy rather than in diagnosing inflammatory skin processes. Special stains contributed to the diagnosis in 21.1% (95% CI 11-32%) of cases. When special stains were performed to diagnose an infection they were effective in 14.7% (95% CI 6-24%) of the cases. When special stains were performed to diagnose any other pathologic processes (neoplasm, inflammation, collagen vascular disease, and amyloid) they were effective in 31.8% (95% CI 24-44%) of the cases.

Granular cell dermatofibroma. A benign tumor that can simulate malignancy.

We report on an unusual dermatofibroma with granular cells. The dermatofibroma contained mitotic figures raising a differential diagnosis that included malignant granular cell tumor. Granular cell dermatofibroma is an uncommon variant, but one that clinicians and surgeons should become aware of to ensure accurate diagnosis.

Congenital fascial dystrophy: the stiff skin syndrome.

Congenital fascial dystrophy is an uncommon disorder that may mimic scleroderma. The skin is bound down and feels "wood hard" on palpation of the trunk and extremities. Sclerodactyly, telangiectases, and nail fold changes are not present. Unlike scleroderma, the onset is at birth. Flexion contractures result and other associated abnormalities may include developmental delay and mild hirsutism. We report a typical case to illustrate the clinical and pathologic findings of patients with this disorder.