Search Results (9)

Histopathologic melanoma diagnosis extends beyond melanocytic cytology to encompass non-melanocytic features: solar elastosis patterns, stromal regression, adnexal relationships, epidermal reaction patterns, and the host inflammatory response. These “old school” low-power clues are particularly valuable on sun-damaged skin, where benign nevi, reactive melanocytic hyperplasia, and melanoma in situ share overlapping features. Quantitative data support two elastosis-based signs: the “umbrella sign” (reduced elastosis beneath the lesion’s central third; PPV (Positive Predictive Value) for nevus, 96%, and NPV (Negative predictive Value) for melanoma, 74%; calculated from raw cohort data) and the “purple fiber sign” (100% specificity, 30% sensitivity for nevus), both from a cohort of 81 actinically damaged lesions. Regression—identified by compressed elastic layers displaced to the reticular dermis, fibrosis, melanophages, and inflammation—aids diagnosis but complicates distinction from surgical scar. The maturation state of tertiary lymphoid structures (TLSs) within the regression zone, ranging from immunosuppressive immature aggregates to anti-tumoral mature structures with germinal centers, may explain the variable prognostic significance of histologic regression. Epidermal hyperplasia over thick melanomas reflects angiogenesis-related changes, while effacement is a practical red flag in spitzoid lesions. Ancillary tests are most productive when morphology has already framed the differential. These non-melanocytic clues remain indispensable as the foundation for rational ancillary testing. Full article

Blastomycosis-like pyoderma (BLP) is a rare chronic inflammatory dermatosis characterized by exuberant vegetative and verrucous plaques, most frequently associated with bacterial colonization, particularly Staphylococcus aureus. Owing to its striking clinical and histopathological resemblance to squamous cell carcinoma (SCC) and other granulomatous or hyperplastic dermatoses, BLP represents a well-recognized diagnostic pitfall, often leading to delayed diagnosis or unnecessary surgical management. We report an unusual case of bilateral auricular BLP in a 58-year-old apparently immunocompetent woman, initially misdiagnosed as SCC. Comprehensive clinicopathological reassessment revealed pseudoepitheliomatous hyperplasia, intraepidermal neutrophilic microabscesses, and a dense mixed inflammatory infiltrate, findings consistent with a reactive rather than neoplastic process. Microbiological cultures confirmed Staphylococcus aureus, supporting the final diagnosis of BLP and guiding effective antimicrobial therapy. To better contextualize this rare presentation, we reviewed all previously reported cases of BLP, summarizing available clinical, histopathological, microbiological, and therapeutic data. This case further raises the possibility of an association between BLP and systemic inflammatory conditions, as the patient subsequently developed severe colitis, highlighting the potential role of immune dysregulation and the gut–skin axis in disease pathogenesis or a possible temporal association, without allowing causal inference. Beyond inflammatory bowel disease, blastomycosis-like pyoderma has been reported in association with a variety of systemic and immune-mediated conditions, including diabetes mellitus, hematologic malignancies, HIV infection, chronic renal failure, autoimmune disorders, and prolonged immunosuppressive therapies. These associations support the concept that BLP represents a hyperinflammatory reaction pattern occurring in the setting of altered immune surveillance rather than a purely infectious disease. Accurate recognition and management of BLP require careful integration of clinical features, histological findings, and microbiological results. Increased awareness of its diverse presentations is essential to avoid misdiagnosis and to ensure appropriate, conservative treatment. Full article

Chromoblastomycosis is a chronic mycosis of the skin and subcutaneous tissue typically caused by traumatic inoculation of dematiaceous fungi of the Herpotrichiellaceae. A 59-year-old male presented with a 12-month history of an asymmetrical, scaly plaque on the left forearm that has been slowly increasing in size. Past medical history included atrial fibrillation on apixaban, hypertension and a cardiac stent. A 4 mm punch biopsy of the left forearm revealed superficial dermal fibrosis with mild pseudoepitheliomatous hyperplasia and granulomatous inflammation with scattered multinucleate histiocytes. There were giant cells with dark brown, somewhat round, yeast-like structures, some with internal septation exhibiting moderate staining for PAS, compatible with Medlar bodies suggestive of chromoblastomycosis. The patient was on rosuvastatin, rendering itraconazole not a possible treatment option, and instead the patient underwent curettage and cautery with two bouts of cryotherapy freeze and thaw cycles. A twelve-month follow-up noted a crusted area on the distal aspect of the scar. A shave biopsy of this area revealed pigmented organisms suggesting a recurrence of chromoblastomycosis. A further excisional biopsy was performed, with no evidence of chromoblastomycosis. This case highlights multiple surgical options for the management of chromoblastomycosis in patients where medical management is contraindicated. It highlights the therapeutic challenge of this disease due to frequent recurrence of lesions and that repeat biopsy may be efficacious in monitoring for recurrence. Full article

Hypertrophic lichen planus (HLP) is a chronic inflammatory skin condition defined by verrucous, pruritic, papules and plaques usually affecting the lower limbs. The diagnosis of HLP is primarily clinical. However, due to its feasible generalized presentation and similarities with other hypertrophic cutaneous disorders, histological evaluation is often necessary. Many dermatological conditions that present with a hypertrophic clinical appearance can arise from a histological lichenoid infiltrate (HCLI). Hence, we provide an overview of the clinical, histopathological, and prognostic features of selected HCLI, including HLP, hypertrophic lichenoid dermatitis, hypertrophic lichen sclerosus (HLS), lichen simplex chronicus (LSC), squamous cell carcinoma (SCC), keratoacanthoma (KA), pseudoepitheliomatous hyperplasia (PEH), viral warts, and lupus erythematosus/lichen planus (LE/LP) overlap. Choosing the appropriate procedure and the anatomical site for an incisional biopsy requires thoughtful consideration to ensure sufficient depth and improve diagnostic accuracy by identifying the histological features specific to each hypertrophic condition. Full article

Perforating dermatoses are dermatologic disorders with transepidermal elimination (TE) of dermal substances. While TE is typically associated with collagen and elastin, it can also occur as a secondary event in other processes, and it is important to keep a broad differential. We present a case of perforating tophaceous gout, which underscores the need for a thoughtful approach to perforating disorders. An updated review of recent literature is also presented. Full article

The increasing popularity of tattooing has paralleled an increase in associated cutaneous reactions. Red ink is notorious for eliciting cutaneous reactions. A common reaction is pseudoepitheliomatous hyperplasia (PEH), which is a benign condition closely simulating squamous cell carcinoma (SCC). Differentiating PEH from SCC is challenging for pathologists and clinicians alike. The exact pathogenesis of these lesions secondary to red ink is not known, and there are no sources outlining diagnostic and treatment options and their efficacy. We present four study cases with different pathologies associated to red ink tattoos including lichenoid reaction, granulomatous reaction, PEH, and an SCC. Additionally, an extensive review of 63 articles was performed to investigate pathogenesis, diagnostic approaches, and treatment options. Hypotheses surrounding pathogenesis include but are not limited to the carcinogenic components of pigments, their reaction with UV and the traumatic process of tattooing. Pathogenesis seems to be multifactorial. Full-thickness biopsies with follow-up is the recommended diagnostic approach. There is no evidence of a single universally successful treatment for PEH. Low-dose steroids are usually tried following a step up in lack of clinical response. For SCC lesions, full surgical excision is widely used. A focus on clinicians’ awareness of adverse reactions is key for prevention. Regulation of the unmonitored tattoo industry remains an ongoing problem. Full article

Background: Cutaneous squamous cell carcinoma (cSCC) is one of the most devastating complications of recessive dystrophic epidermolysis bullosa (RDEB). We recently demonstrated a reduction in immune cell peritumoral infiltration in RDEB patients with cSCC, together with a reduction in CD3+, CD4+, CD68+ and CD20 lymphocytes as compared to primary and secondary cSCC in patients without RDEB. Recently, new molecules, such as high mobility group box 1 (HMGB1), T cell immunoglobulin, mucin domain 3 (TIM-3) and Heme oxygenase-1 (HO-1), have been shown to play a role in antitumoral immunity. Objective: Patients with RDEB are known to be at increased risk of developing skin cancers, including the dreaded squamous cell carcinoma of the. Tendentially, cSCCs that arise in the context of EBDR are more aggressive and lead to statistically significant bad outcomes compared to cSCCs developed on the skin of patients without EBDR. In an attempt to study the microenvironment of these lesions, we conducted an immunohistochemical analysis study of proteins that could be actively involved in the genesis of this type of malignant neoplasms. Methods: In this retrospective study, the OH1-HMGB1-TIM3 activation axis, as correlated to the T lymphocytes cell count, was assessed in biopsy samples from 31 consecutive cases consisting of 12 RDEB patients with cSCC, 12 patients with primary cSCC and 7 RDEB patients with pseudoepitheliomatous cutaneous hyperplasia. Parametric Student’s t-test was applied for normally distributed values, such as CD4+ and CD8+, and non-parametric Mann–Whitney test for non-normally distributed values, such as HMGB-1, TIM-3 and HO-1. Results: In RDEB patients with cSCC and with pseudoepitheliomatous hyperplasia, the expression of CD4 T helper lymphocytes was lower than in the peritumoral infiltrate found in primary cSCC. CD8 cytotoxic T lymphocytes were increased in primary cSCC compared to the other two groups. An increased HMGB1 expression was evident in both primary and RDEB cSCC. TIM3 expression was higher in RDEB patients with cSCC compared to the other two groups. A significantly reduced immunohistochemical expression of HO-1 was evident in the tumoral microenvironment of cSCC-RDEB as compared to primary cSCC. Conclusions: These data suggest that a reduced immune cell peritumoral infiltration in RDEB patients could be responsible, in the complexity of the mechanisms of carcinogenesis and host response, of the particular aggressiveness of the cSCC of RDEB patients, creating a substrate for greater local immunosuppression, which, potentially, can “open the doors” to development and eventual metastasis by this malignant neoplasm. Full article

Oral granular cell tumor (GCT) is a relatively rare, benign lesion that can easily be misdiagnosed. Particularly, the presence of pseudoepitheliomatous hyperplasia might, in some cases, lead to the hypothesis of squamous cell carcinoma. Surgical excision is the treatment of choice. Recurrence has been reported in up to 15% of cases treated with conventional surgery. Here, we reported a case of GCT of the tongue in a young female patient, which was successfully treated through 445 nm diode laser excision. Laser surgery might reduce bleeding and postoperative pain and may be associated with more rapid healing. Particularly, the vaporization effect on remnant tissues could eliminate GCT cells on the surgical bed, thus hypothetically leading to a lower rate of recurrence. In the present case, complete healing occurred in 1 week, and no recurrence was observed after 6 months. Laser surgery also allows the possibility to obtain second intention healing. Possible laser-induced histopathological artifacts should be carefully considered. Full article

Elephantiasis nostras verrucosa is a rare disorder that results from chronic obstructive lymphedema. It is characterized clinically by deforming, nonpitting edema; malodorous hyperkeratosis with generalized lichenification; cobblestoned papules; and verrucous changes, that often result in extreme enlargement of the involved body part. Although elephantiasis nostras verrucosa is striking in clinical appearance, biopsy reveals only moderately abnormal findings: pseudoepitheliomatous hyperplasia with dilated lymphatic spaces in the dermis, accompanied by chronic inflammation and fibroblast proliferation. The term elephantiasis nostras (nostras means “from our region”) has traditionally been used to differentiate temperate zone disease from the classic disease process, elephantiasis tropica, which is defined by chronic filarial lymphatic obstruction caused by Wuchereria bancrofti, Wuchereria malayi, or Wuchereria pacifica. We present a case report of elephantiasis nostras verrucosa arising as a result of lymphedema praecox. (J Am Podiatr Med Assoc 98(1): 66–69, 2008) Full article