A 61-year-old man presented for evaluation of a bruise-like lesion of the right knee. He was found to have an ill-defined, light brown patch with focal areas of dark red and brown. The histopathologic diagnosis was consistent with amyloidosis. Further subtyping showed that the amyloid protein was AL (κ). A systemic evaluation failed to show internal involvement. Amyloidosis comprises a spectrum of diseases, which range from systemic to localized cutaneous types, and is characterized by the extracellular deposition of amyloidosis protein as beta-pleated sheets. The forms of amyloidosis are differentiated by the specific types of protein-derived amyloidosis fibers. Both nodular and primary systemic amyloidosis can present as nodules on the skin owing to deposition of AL type amyloid protein. Primary systemic amyloidosis, which carries a poorer prognosis than does nodular amyloidosis, also may give rise to ecchymoses and many other cutaneous and extracutaneous findings. Histopathologic features are similar in both cases and involve the deposition of amorphous, eosinophilic material in the dermis. Nodular amyloidosis may progress to primary systemic disease in up to 50% of cases. Because our patient had no systemic involvement and the lesions did not appear nodular in nature, the patient was given a diagnosis of primary localized AL cutaneous amyloidosis. Routine follow-up for this patient is necessary to detect any potential disease progression.

HTLV-1 is a virus that is endemic in southwesternJapan and the Caribbean and has been implicatedin the development of ATLL. ATLL, which is anuncommon malignant condition of peripheralT-lymphocytes, is characterized by four clinicalsubtypes, which include acute, lymphomatous,chronic, and smoldering types, that are based onLDH levels, calcium levels, and extent of organinvolvement. We present a 52-year- old woman withpruritic patches with scale on the buttocks and withtender, hyperpigmented macules and papules oftwo-years duration. Histopathologic examinationwas suggestive of mycosis fungoides, laboratoryresults showed HTLV-I and II, and the patient wasdiagnosed with primary cutaneous ATLL. We reviewthe literature on HTLV-1 and ATLL and specifically theprognosis of cutaneous ATLL. The literature suggeststhat a diagnosis of ATLL should be considered amongpatients of Caribbean origin or other endemicareas with skin lesions that suggest a cutaneousT-cell lymphoma, with clinicopathologic features ofmycosis fungoides. Differentiation between ATLLand cutaneous T-cell lymphoma is imperative as theyhave different prognoses and treatment approaches.

Diffuse sebaceous-gland hyperplasia is a rarevariant of sebaceous-gland hyperplasia that isdistinct from the well-known circumscribed type.The term presenile sebaceous hyperplasia has beenutilized to describe this entity that is distinguishedby specific features, which include confluence oflesions that results in the formation of large plaqueson the face, the sparing of periorificial regions, andhighly functional glandular hyperplasia that resultsin excessive sebaceous secretion. We present a43-year-old woman with monomorphous, skincoloredand yellow, smooth 1- to-3-mm papules,some with central umbilication, that spare theperiorificial zones. Histopathologic examination wassuggestive of diffuse sebaceous-gland hyperplasia.Differential diagnosis of this condition is broad andincludes syndromes that are associated with multiplefacial papules and malignant conditions, such asMuire-Torre syndrome and Cowden syndrome. Itis important to be aware of this condition in orderto consider appropriate treatment options, such asisotretinoin and to avoid unnecessary diagnostictests.

Anaplastic large-cell lymphomas (ALCLs) are agroup of CD30-positive non-Hodgkin lymphomasthat are linked by common morphologic andimmunophenotypic features but have varyingclinical and genetic characteristics. The World HealthOrganization classification currently recognizes threesubtypes of ALCL: systemic anaplastic lymphomakinase-positive ALCL, systemic anaplastic lymphomakinase-negative (ALK-) ALCL, and primary cutaneousALCL. Here we present a 42-year-old man with ahistory of systemic ALK- ALCL, who was in remissionfor six months before relapsing with skin-limitedanaplastic large-cell lymphoma.

Gyrate erythema, which also is known as erythemaannulare centrifugum (EAC), is a reactive dermatitisthat is thought to occur in response to an underlyingtrigger. The superficial form is characterized bythe typical, centrifugally-expanding, annular,erythematous patches or plaques with a distincttrailing scale. The deep form also is a centrifugallyexpanding,erythematous plaque but with induratedborders and absence of scale. These cutaneousfindings are thought to be reactive, most often inresponse to infections or drugs and, less likely, tounderlying malignant conditions.

The association between multiple pilomatricomasand the autosomal dominant neurodegenerativedisorder myotonic dystrophy has been described inthe literature. Although the mechanism is unknown,it is hypothesized that the dystrophia myotonicaprotein kinase mutation in myotonic dystrophyaffects intracellular calcium levels, which alterproliferation and terminal differentiation that leads tocells that are observed in pilomatricomas. We presenta patient with multiple, symptomatic pilomatricomasand myotonic dystrophy, with a strong family historyof both of these rare disorders.

Cutis verticis gyrata that involves only the face isa rare presentation of this even rarer cutaneousanomaly. We present a 61-year-old man, whodeveloped primary essential progressive cutis verticisgyrata of the face.

Cowden syndrome (CS) is a genetic cancerpredisposition syndrome that is associated withgermline mutations in the phosphate and tensinhomologue deleted on chromosome ten (PTEN)tumor suppressor gene. It is characterizedby the formation of benign and malignanttumors. Characteristic benign tumors includetrichilemmommas, acral keratoses, mucocutaneousneuromas, and oral papillomas. The most commonmalignant condition include breast, thyroid, andendometrial cancers. We present a case of a30-year-old woman with CS, who initially presentedwith trichilemmomas that were misdiagnosed ascomedonal acne. Recognition of the presentingfeatures of CS is important to ensure proper referral,management, and treatment for these patients.