Linear scleroderma in an adolescent woman treated with methotrexate and excimer laser.

A 17-year-old Caucasian woman presented for evaluation and treatment of a tender expanding linear plaque on her left flank. Biopsy findings were consistent with morphea. Treatment initially included intralesional steroid injections and topical calcipotriene ointment, followed by methotrexate and excimer laser. The lesion decreased in size considerably with relief of symptomatic discomfort by 7 months. An excisional biopsy of a persistent eroded papule on the superior aspect of the morphea plaque revealed dermal thickening and sclerosis with superimposed perforation of a calcified nodule. Localized scleroderma, or morphea, is an autoimmune disease of the skin and underlying subcutaneous tissue primarily affecting the pediatric population. The excimer laser has been reported to effectively treat a variety of dermatologic conditions, including morphea. Its mechanism of action may be via depletion of T cells, altering apoptosis-mediating molecules and decreasing cytokine expression. Methotrexate is also useful for the acute and deep forms of morphea and has been shown to decrease levels of inter leukins-2 and -6, tenascin, and mast cells. This patient had a good clinical response with a combination of these two modalities. The epidermal perforation with transepidermal elimination of calcified necrotic collagen is a unique complication that may have been secondary to this combination treatment modality.

Variability in the Histopathological Diagnosis of Non-Melanocytic Lesions Excised to Exclude Melanoma.

INTRODUCTION: The differential diagnosis of lesions excised to exclude melanoma include a variety of benign and malignant melanocytic and non-melanocytic lesions. OBJECTIVES: We examined the variability between pathologists in diagnosing non-melanocytic lesions. METHODS: As part of a larger study prospectively examining the diagnosis of lesions excised to exclude melanoma in 198 patients at a primary care skin cancer clinic in Newcastle, Australia, we compared diagnosis made by 5 experienced dermatopathologists, of 44 non-melanocytic lesions in 44 patients aged 22-90. RESULTS: Forty-four lesions (out of 217 in total) were non-melanocytic. Among the 5 pathologists who examined each case there was marked variability in the terminology used to diagnose each case. The most common variability was found between seborrheic keratosis, large cell acanthoma, solar lentigo, and lichenoid keratosis. The diagnosis made by the majority of the pathologists was deemed to be the reference diagnosis. Versus majority diagnosis, 4% of benign lesions were considered malignant, and 7% of malignant diagnoses were considered as benign. CONCLUSIONS: The different terminology adopted and lack of consensus in the diagnosis of these non-melanocytic lesions in this setting suggests that training AI systems using gold standards may be problematic. We propose a new management classification scheme called MOLEM (Management of Lesions Excised to exclude Melanoma) which expands the previously described MPATH-dx to include non-melanocytic lesions.

Assessment of a Diagnostic Classification System for Management of Lesions to Exclude Melanoma.

Importance: The proposed MOLEM (Management of Lesion to Exclude Melanoma) schema is more clinically relevant than Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MATH-Dx) for the management classification of melanocytic and nonmelanocytic lesions excised to exclude melanoma. A more standardized way of establishing diagnostic criteria will be crucial in the training of artificial intelligence (AI) algorithms. Objective: To examine pathologists' variability, reliability, and confidence in reporting melanocytic and nonmelanocytic lesions excised to exclude melanoma using the MOLEM schema in a population of higher-risk patients. Design, Setting, and Participants: This cohort study enrolled higher-risk patients referred to a primary care skin clinic in New South Wales, Australia, between April 2019 and December 2019. Baseline demographic characteristics including age, sex, and related clinical details (eg, history of melanoma) were collected. Patients with lesions suspicious for melanoma assessed by a primary care physician underwent clinical evaluation, dermoscopy imaging, and subsequent excision biopsy of the suspected lesion(s). A total of 217 lesions removed and prepared by conventional histologic method and stained with hematoxylin-eosin were reviewed by up to 9 independent pathologists for diagnosis using the MOLEM reporting schema. Pathologists evaluating for MOLEM schema were masked to the original histopathologic diagnosis. Main Outcomes and Measures: Characteristics of the lesions were described and the concordance of cases per MOLEM class was assessed. Interrater agreement and the agreement between pathologists' ratings and the majority MOLEM diagnosis were calculated by Gwet AC1 with quadratic weighting applied. The diagnostic confidence of pathologists was then assessed. Results: A total of 197 patients were included in the study (102 [51.8%] male; 95 [48.2%] female); mean (SD) age was 64.2 (15.8) years (range, 24-93 years). Overall, 217 index lesions were assessed with a total of 1516 histological diagnoses. Of 1516 diagnoses, 677 (44.7%) were classified as MOLEM class I; 120 (7.9%) as MOLEM class II; 564 (37.2%) as MOLEM class III; 114 (7.5%) as MOLEM class IV; and 55 (3.6%) as MOLEM class V. Concordance rates per MOLEM class were 88.6% (class I), 50.8% (class II), 76.2% (class III), 77.2% (class IV), and 74.2% (class V). The quadratic weighted interrater agreement was 91.3%, with a Gwet AC1 coefficient of 0.76 (95% CI, 0.72-0.81). The quadratic weighted agreement between pathologists' ratings and majority MOLEM was 94.7%, with a Gwet AC1 coefficient of 0.86 (95% CI, 0.84-0.88). The confidence in diagnosis data showed a relatively high level of confidence (between 1.0 and 1.5) when diagnosing classes I (mean [SD], 1.3 [0.3]), IV (1.3 [0.3]) and V (1.1 [0.1]); while classes II (1.8 [0.2]) and III (1.5 [0.4]) were diagnosed with a lower level of pathologist confidence (≥1.5). The quadratic weighted interrater confidence rating agreement was 95.2%, with a Gwet AC1 coefficient of 0.92 (95% CI, 0.90-0.94) for the 1314 confidence ratings collected. The confidence agreement for each MOLEM class was 95.0% (class I), 93.5% (class II), 95.3% (class III), 96.5% (class IV), and 97.5% (class V). Conclusions and Relevance: The proposed MOLEM schema better reflects clinical practice than the MPATH-Dx schema in lesions excised to exclude melanoma by combining diagnoses with similar prognostic outcomes for melanocytic and nonmelanocytic lesions into standardized classification categories. Pathologists' level of confidence appeared to follow the MOLEM schema diagnostic concordance trend, ie, atypical naevi and melanoma in situ diagnoses were the least agreed upon and the most challenging for pathologists to confidently diagnose.

Necrotic leg ulcers secondary to hydrophilic polymer gel emboli.

A 63-year-old man presented with left lower extremity ischemia and pain. Left lower extremity angiography revealed calcification throughout the superficial femoral artery, prompting atherectomy and angioplasty with a drug-coated balloon. About 1 week after the procedure, he developed angulated ulcers with central eschar on the left lower extremity and was referred to the dermatology clinic. A biopsy showed cutaneous intravascular foreign material consistent with hydrophilic polymer gel. In patients who develop retiform purpura and ulcerations after endovascular procedures, the diagnosis of hydrophilic polymer embolus should be considered. Treatment consists of supportive care, making early identification vital to avoid unnecessary amputation.

Spontaneous regression of primary cutaneous diffuse large B-cell lymphoma, leg type with significant T-cell immune response.

We report a case of histologically confirmed primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT) that subsequently underwent spontaneous regression in the absence of systemic treatment. The case showed an atypical lymphoid infiltrate that was CD20+ and MUM-1+ and CD10-. A subsequent biopsy of the spontaneously regressed lesion showed fibrosis associated with a lymphocytic infiltrate comprising reactive T cells. PCDLBCL-LT is a cutaneous B-cell lymphoma with a poor prognosis, which is usually treated with chemotherapy. We describe a case of clinical and histologic spontaneous regression in a patient with PCDLBCL-LT who had a negative systemic workup but a recurrence over a year after his initial presentation.

Graft-versus-host Disease-associated Angiomatosis Treated With Topical Timolol Solution.

INTRODUCTION: Scleroderma-like graft-versus-host disease (GVHD) is an uncommon subtype of chronic GVHD. Vascular lesions rarely arise within areas of scleroderma-like changes and until recent- ly have not been considered to be related entities. Kaffenberg et al1 have grouped this heterogeneous collection of vascular lesions under the term GVHD-associated angiomatosis. Treatment modalities thus far have been mostly ineffective. Topical timolol solution has been used in the treatment of superficial infantile hemangiomas with good success. Here the authors report the first case of GVHD-associated angiomatosis treated with topical timolol solution. METHODS AND MATERIALS: Timolol 0.5% solution was applied daily to 3 lesions on the lower extremities of their patient for 3 months. RESULTS: All lesions decreased in friability and frequency of spontaneous hemorrhage. Le- sions remained stable in size throughout treatment duration, with no growth observed in any lesion. Granulation tissue surrounding all lesions was markedly reduced after the treatment period. CONCLUSION: Topical timolol remains a promising therapeutic option in the treat- ment of GVHD-associated angiomatosis.

Paraneoplastic cutaneous lupus secondary to esophageal squamous cell carcinoma.

Sporadic subacute cutaneous lupus erythematosus (SCLE) in an elderly man does not fit a typical demographic for the disease process. Using the McLean's criteria we were able to establish a temporal relationship between the patient's diagnosis of esophageal squamous cell carcinoma (SCC) and his dermatosis, both of which responded to cytotoxic chemotherapy. The clinical presentation and progression of the clinical illness is supportive of a very unusual and not previously reported paraneoplastic SCLE secondary to esophageal SCC.

Langerhans cell histiocytosis associated with myelodysplastic syndrome in adults.

BACKGROUND: Myelodysplastic syndrome (MDS) is a group of bone marrow disorders associated with dyplasia of myeloid elements that may have cutaneous manifestations including infections, vasculitis, Sweet's syndrome, pyoderma gangrenosum, erythema elevatum diutinum, and leukemia cutis. These cutaneous manifestations are attributed to the underlying bone marrow defect. Langerhans cell histiocytosis (LCH) is primarily a pediatric disease, and rarely LCH has been described in association with pediatric MDS. We are aware of only a single case report of LCH associated with MDS in an adult. METHODS: We report two new cases of LCH in elderly patients with underlying MDS. The specimens were examined by routine microscopy as well as immunohistochemical stains for S100 protein and CD1a. RESULTS: Both patients were elderly men with established diagnoses of MDS. One presented with a solitary pruritic papule while the other had a 2-year history of erythematous papules involving the trunk and extremities. Histologic examination revealed intraepidermal and dermal collections of mononuclear cells with reniform nuclei. The cells were strongly positive for S100 and CD1a, confirming their identity as Langerhans cells. CONCLUSION: Cutaneous LCH may be associated with underlying MDS in adults and should be considered in the differential diagnosis of cutaneous eruptions in patients with MDS.