Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
➤ Gửi thông báo lỗi ⚠️ Báo cáo tài liệu vi phạmNội dung chi tiết: Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2 Arkansas for Medical Sciences, Little Rock, Arkansas, U.S.A.I. BENIGN EPITHELIAL NEOPLASMSA. Seborrheic KeratosisSynonym: stucco keratosis.Clinical FeaturesSeborrheic keratoses (SKs) are common benign cutaneous neoplasms seen most frequently in adults and the elderly without a gender predilection. Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2With the exception of palms, soles, and mucosal surfaces, SKs may be seen on any site. They present as scaly, greasy, raised growths that range from sEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
everal millimeters to a centimeter in diameter and are described as having a "stuck-on" appearance, suggesting that they could be simply lilted from t23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2wn as stucco keratosis tends to occur more commonly as verrucous plaques on the extremities. Multiple small SKs may be seen on the face, in particular, the cheeks of dark-skinned patients. This condition, referred to as dermatosis papulosis nigra, is seen twice as frequently in women than in men. In Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2verted follicular keratosis has been considered a variant of an irritated SK. Recent research shows distinct antigenic expression, which may ultimateEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
in classifying these lesions as distinct entities (1,2).ImagingAs SKs are benign and not believed to undergo malignant transformation, imaging studies23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2s" on dermoscopy, and has been helpful clinically in distinguishing pigmented SKs from melanoma (3).Histologic FeaturesWhile there are many histologic variants of SK, each of these shares certain basic histologic characteristics. Each variant demonstrates acanthosis with an expansion of the basaloid Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2 keratinocytes, overlyinghyperkeratosis without parakeratosis, an abrupt transition from normal adjacent epidermis and a flat horizontal base to the lEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
esion (Fig. 1). The basaloid keratinocytes are uniform in size and appearance and have bland cytologic features. Other variants demonstrate a reticula23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2aloid “clones" (Fig. 3), but no atypical keratinocytes. In the so-called clonal variant of SK, foci of parakeratosis may be present overlying the clones of basaloid keratinocytes. Cytologic atypia is present only in very irritated SKs. Except when irritated or markedly inflamed, mitoses are scant. A Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2typical mitoses are not seen. In most types of SKs, there is a very flat base to the lesion with underlying papillary dermal fibrosis. Some SKs have aEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
papillomatous growth pattern, the stucco keratoses (Fig. 4), while in others the surface is relatively smEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
y in so much as one is able to recognize the pattern to make the diagnosis. The histologic features of dermatosis papulosis nigra cannot be distinguis23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2required to make a diagnosis of SK. Research has demonstrated that the neoplastic cells express keratins 5 and 14, similar to the normal keratin expression of basal keratinocytes.1476Hiatt Ct al.Figure 1 Seborrheic keratosis. There ts expansion of basaloid kcratinocytcs that arc uniform in size and Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2have bland cytologic features. The epidermis is acanthotic with overtying hyperkeratosis. no parakeratosis, and a flat horizontal base to the lesionFiEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
gure 3 Seborrheic keratosis, clonal. The epidermis has small intraepidermal basaloid "clones." Foci of parakeratosis may be present overlying these cl23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2ng from the overlying epidermis and enveloping several horn cysts.Differential DiagnosisThe histologic differential diagnosis includes epidermal nevus, verruca vulgaris, and less commonly, eccrine poroma and squamous cell carcinoma in situ (SCCIS). Epidermal nevi are histologically identical to SKs Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2and can only be distinguished on the basis of a clinical history of appearance during early childhood (as opposed to SKs that are growths associated wEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
ith middle to later life). Verruca vulgaris can sometimes be distinguished on the basis of the presence of overlying columns of parakeratosis, clumpin23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2 keratosis. The cpidcrms is mildly acanthotic with a papillomatous growth pattern.horn cysts are not usually seen in verruca vulgaris. In other cases, such a distinction may be virtually impossible. Eccrine poromas demonstrate a similar growth pattern but are characterized by the presence of small i Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2ntraepithelial ducts and by the absence of horn cysts. Further, vascular ectasia within the dermis and reduplicated basement membrane, resulting in foEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
ci of eosinophilic "hyaline," are seen in poromas, but not in SKs. Cytologic atypia that characterizes SCCIS is only present in markedly inflamed and 23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2nflammatory infiltrates. This is especially difficult when there Is a spindle cell configuration to the neoplastic keratinocytes in the setting of mitotic activity and marked inflammation. However, true cytologic alypia and pleomorphism are not present in SKs, in contrast to squamous cell carcinomas Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2 (SCCs).Chapter 23: Pathology of Selected Skin Lesions oFigure 5 Inverted follicular keratosis. There IS an endophytic growth pattern with a central,Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
keratin-filled dell and abundant squamous eddies toward the periphery of the dermal nodule.Inverted follicular keratosis may also show a marked simila23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2toses are characterized by an invaginated growth pattern with a central, keratin-filled dell and abundant squamous eddies (Fig. 5). While squamous eddies may be seen in very inflamed and irritated SKs, they do not demonstrate the same architectural features as are seen in inverted follicular keratos Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2es.AsMCMted SyndromesThe rapid eruption of numerous SKs has been associated with internal malignancies in a syndrome known as Leser-Trelat. This is aEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
very controversial syndrome. Those who believe it exists suggest that the SKs represent a paraneoplastic process, perhaps induced by epidermal growth 23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2sSKs do not require any medical treatment. In some cases, they are removed with simple shave excisional biopsies for cosmetic reasons. In other situations, the clinical resemblance to malignant melanoma results in a surgical excision to exclude the latter condition. These are benign tumors, with no Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2tendency for infiltrative growth or metastasis and only a slight chance for local recurrence if not fully excised.B. Pilar CystSynonyms: trichilemmalEbook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2
cyst and isthmus-catagen cyst.IntroductionNinety percent of pilar cysts (PCs) occur on the scalp, often as multiple lesions, with a small percentage a23Pathology of Selected Skin Lesions of the Head and NeckKim M. Hiatt, Shayesteh Pashaei, and Bruce R. Smoller Department of Pathology, University of Ebook Surgical pathology of the head and neck (Vol 3 - 3/E): Part 2litary in only 30% of cases, with 10% having more than 10 cysts (3).Gọi ngay
Chat zalo
Facebook