Wolf isotopic response describes the onset of a new dermatosis at the site of a previous, healed dermatosis, which is usually a herpes zoster infection. Fibroelastolytic papulosis is a poorly understood elastolytic condition defined by a loss of elastic fibers specific to the papillary dermis. The present report describes a case of fibroelastolytic papulosis with onset following herpes zoster infection. This association provides new evidence for an immunopathogenic origin for fibroelastolytic papulosis and further supports current theories of the pathogenesis of Wolf isotopic response.

We report a patient with new-onset ulcerated granuloma annulare with concomitant involvement of B-cell leukemia. A granuloma annulare-like eruption with concomitant B cell chronic lymphocytic leukemia involvement in the skin is extremely rare, as only three cases have been previously reported in the literature to our knowledge. Given the rarity of ulceration in conventional granuloma annulare, it is possible this finding may serve as a diagnostic clue for underlying malignancy.

Hair re-pigmentation in adults is a rare phenomenon. We describe a 58-year-old woman who developed hair re-pigmentation on her vertex scalp as a marker of underlying melanoma. Histopathology revealed a nodular melanoma that was surrounding but not invading follicular epithelium. To our knowledge, there have only been 4 other previously published cases describing hair re-pigmentation in the setting of scalp melanoma. Focal hair re-pigmentation in adults should prompt a thorough evaluation for an underlying melanoma.

The original article was published on February 15, 2024 and corrected on April 15, 2024.The revised version of the article corrects Figure 2. The changes appear in the revised online PDF copy of this article.

Spindle cell lipomas are a rare type of lipoma usually presenting in middle-aged to older men, often located on the posterior neck or shoulder; presentation on the foot is exceptionally uncommon. We report a 24-year-old man with spindle cell lipomas on the hallux of his left foot. He experienced an uneventful recovery after excision of the mass. We discuss clinical, radiologic, and histopathologic features of spindle cell lipomas and we review the differential diagnosis at this anatomic site.

Background

Graft-vs-host disease (GVHD) is a rare and often fatal complication of orthotopic liver transplantation (OLT). The skin is frequently involved early in disease progression, but clinical and histopathological features may be nonspecific, presenting a diagnostic challenge. While the detection of peripheral blood chimerism has been proposed as a diagnostic criterion for post-OLT GVHD, it is not known whether peripheral blood chimerism is an absolute requirement for the diagnosis.

Materials and methods

We report a case of a 57-year-old man who developed post-OLT GVHD with cutaneous, enteric, and bone marrow involvement. We also review the epidemiology, pathogenesis, clinical presentation, histopathology, molecular diagnostic techniques, and treatment of GVHD following liver transplantation.

Results

In our patient, analysis of the peripheral blood by short-tandem repeat polymerase chain reaction did not detect circulating donor lymphocytes. Donor lymphocytes were detected in the buccal mucosa, however, confirming the diagnosis. A review of chimerism patterns in 63 previously published cases of post-OLT GVHD reveals that this is the first reported case in which chimerism was absent in the peripheral blood but present in another site.

Conclusions

Peripheral blood chimerism may be absent in cases of post-OLT GVHD. A combination of clinical, histopathological, and molecular features is therefore required to make this challenging diagnosis.

Cutaneous lichen planus is classically characterized by violaceous, pruritic, planar papules and plaques, most commonly affecting the extremities. Lichen planus following radiation therapy is extremely rare and lichen planus following radiation therapy for prostate carcinoma has not been previously reported in the literature. We report a 66-year-old man who presented to the dermatology clinic with a symmetric pruritic eruption affecting the pelvic and gluteal region within two months of radiation therapy targeting the prostate and pelvic lymph nodes for prostate adenocarcinoma. The patient did not have a prior history of lichen planus. Physical examination demonstrated well demarcated, violaceous papules and plaques in a circumferential band-like distribution on the bilateral gluteal, lumbosacral, and pelvic region. In addition, he had a few discrete lesions on the calves and dorsal feet. Punch biopsy revealed an acanthotic epidermis with "saw-tooth" rete ridges and a lichenoid inflammatory infiltrate. A diagnosis of hypertrophic lichen planus was made, reinforcing the importance for clinicians to recognize radiation therapy as a risk factor for developing lichen planus despite no prior history of lichen planus.

Complications from radiation exposure during fluoroscopic guidance of cardiac catheterization may occur. With repeated procedures, the risk for cutaneous injuries increases. Herein, we describe a 59-year-old man with extensive coronary artery disease, who had undergone multiple revascularization procedures and developed a non-healing ulcer on his left inferior scapula. The patient’s medical history, physical exam findings, and histopathology gave clues to a case of radiation-induced dermatitis and necrosis.

Background

The absence of a discrete mass, surrounding signal abnormality and solid enhancement are imaging features that have traditionally been used to differentiate soft-tissue arteriovenous malformations from vascular tumors on MRI. We have observed that these findings are not uncommon in arteriovenous malformations, which may lead to misdiagnosis or inappropriate treatment.

Objective

To estimate the frequency of atypical MRI features in soft-tissue arteriovenous malformations and assess their relationship to lesion size, location, tissue type involved and vascular architecture.

Materials and methods

Medical records, MRI and histopathology were reviewed in consecutive patients with soft-tissue arteriovenous malformations in a multidisciplinary vascular anomalies clinic. Arteriovenous malformations were divided into those with and without atypical MRI findings (perilesional T2 signal abnormality, enhancement and/or a soft-tissue mass). Lesion location, size, tissue involved and vascular architecture were also compared between groups. Tissue stains were reviewed in available biopsy or resection specimens to assess relationships between MRI findings and histopathology.

Results

Thirty patients with treatment-naïve arteriovenous malformations were included. Fifteen lesions demonstrated atypical MRI. There was no difference in age, gender, lesion size or involved body part between the groups. However, more than half of the atypical lesions demonstrated multicompartmental involvement, and tiny intralesional flow voids were more common in atypical arteriovenous malformations. Histopathology also differed in atypical cases, showing densely packed endothelial cells with connective tissue architectural distortion and edema.

Conclusion

Arteriovenous malformations may exhibit features of a vascular tumor on MRI, particularly when multicompartmental and/or containing tiny internal vessels. These features are important to consider in suspected fast-flow vascular malformations and may have implications with respect to their treatment.

Background

Metastases to the skin are found with increased frequency at certain sites, such as the scalp, but the biological factors that influence this distribution are not understood.

Objective

We aimed to compare the proportional frequency of metastases at various cutaneous locations with the immunologic microenvironments at those sites.

Methods

We retrospectively identified all biopsy specimens of cutaneous metastases diagnosed at our institution from 1991 to 2014 (n = 1984) and mapped their anatomic distribution while controlling for regional surface area. Using a separate, mapped cohort of normal-appearing skin samples (n = 140), we measured the density of regulatory T cells, CD4(+) effector T cells, and CD8(+) T cells by flow cytometry.

Results

Per unit surface area, cutaneous metastases arise most commonly on the head and neck, followed by the trunk, upper extremities, and lower extremities, respectively. Sites with more frequent metastases tend to contain a greater density of regulatory T cells and a lower proportion of CD8(+) T cells (P < .05).

Limitations

Immunologic factors were only assessed in control tissue and were not measured from patients with metastatic disease in this correlative single-center study.

Conclusion

The distribution of cutaneous metastases follows the distribution of regulatory and effector T cells in skin. Further studies are required to prove a mechanistic association between local immunologic factors and the development of cutaneous metastases.