Syringometaplasia: variants and underlying mechanisms

Apocrine Papillary Hidrocystoma With Mucinous Metaplasia (Goblet Cell Type): A Case Report and Review of the Literature

ABSTRACT

Mucinous metaplasia (goblet cell type) is exceptionally rare in the skin. This is the second case of apocrine papillary hidrocystoma with mucinous metaplasia (goblet cell type) and a review of the literature exploring the significance and frequency of mucinous metaplasia with goblet cells in nongenital skin. The patient is an elderly man who presented with a blue-pigmented nodule on the scalp that was clinically suggestive of an atypical nevus. Histologically, the lesion was composed of a simple cyst of cuboidal cells with decapitation secretion and mucinous metaplasia with goblet cells. Papillary formation was identified in the cysts. Most cases of cutaneous mucinous metaplasia have been reported on genital skin, usually after chronic inflammation of the area. This type of mucinous metaplasia is categorized as benign mucinous metaplasia of the genitalia (BMM) and is believed to be unrelated to apocrine glands owing to the different histologic features and absence of apocrine differentiation by immunohistochemistry. Mucinous metaplasia (goblet cell type) has been previously reported in benign adnexal tumors (eccrine acrospiroma/hidroadenoma, mixed tumor, and syringocystadenoma papilliferum) and in malignant tumors (apocrine hidradenocarcinoma and squamous cell carcinoma). To date, mucinous metaplasia has not been identified in the histologically normal apocrine glands.

Cutaneous eccrine inflammation and necrosis: review of inflammatory disorders affecting the eccrine apparatus including new associations

Despite being frequently overlooked during the examination of histopathological sections, eccrine sweat glands can offer clues for diagnosing various skin conditions. They provide important functions and can lead to several diseases when inflamed or injured. This review article provides information regarding eccrine physiology as well as well-established and novel entities that occur in association with eccrine gland pathology.

[Cutaneous complications following hematopoietic stem cell transplantation]

BACKGROUND

Hematopoietic stem cell allograft is a treatment for patients with severe constitutional or acquired hematopoietic system diseases. This act is always linked to complications requiring multidisciplinary care. Our study describes the post-allograft cutaneous complications.

METHODS

A prospective study was conducted at the Hematology department of "20 Août Hospital" in Casablanca during a period going from January 2018 to December 2020; including all patients who presented acute or chronic cutaneous complications post-allograft.

RESULTS

Twenty-five patients were included. All patients received induction chemotherapy (Busulfan/Fludarabine or Busulfan/Melphalan). A skin infection was found in 8 patients : four cases of Malassezia folliculitis, one case of perineal zona, one case of genital herpes, one case of varicella and one case of Candida sepsis. The acute graft versus host reaction was found in 3 patients, revealed by an erythematous rash all over the body. The chronic graft versus host reaction was found in five patients on a lichenoid form. Nine patients had a hyperpigmentation of the folds followed by detachment in the same areas, concluding to a Busulfan toxidermy.

DISCUSSION

Hematopoietic stem cell allograft has many complications. The literature mainly specifies hematological and digestive complications, while skin complications are little described. Our series is special by reporting different types and mechanisms of skin complications that can occur; with a predominance of skin graft-on-host reactions and infections. It also reports an unusual Busulfan toxidermy.

Ciliated and Mucinous Adenomatous Syringometaplasia: The Missing Link of the "Ciliated Eccrine Metaplasia" Theory in the Histogenesis of Cutaneous Eccrine Ciliated Cyst?

ABSTRACT

A variety of metaplastic changes has been reported in eccrine ducts and glands with squamous and mucinous syringometaplasia representing the most common histopathologic patterns. In the current case, a previously unreported variant of syringometaplasia was described in a female newborn with a 2-cm occipital cutaneous defect consistent with cutis aplasia. Over a more than 1-year period of local treatment, an enlarging plaque associated with local alopecia developed at the site of the original ulcerated area. A local excision demonstrated a superficial hypertrophic scar associated with a complete loss of hair follicles. In addition, there was a proliferation of eccrine glands and ducts lined by cuboidal epithelial cells arranged in a linear distribution beneath the scar area. Focal anastomosing of the proliferative ducts was identified. In few dilated ducts, the epithelial lining was composed of an inner layer of columnar cells with well-formed apical cilia and intracytoplasmic mucin and an outer layer of myoepithelial cells. The mucinous and ciliated cells were positive for epithelial membranous antigen and carcinoembryonic antigen, but negative for estrogen receptors, progesterone receptors, and thyroid transcription factor-1. Because this variant of eccrine metaplasia has not hitherto been reported in the literature, the term ciliated and mucinous adenomatous syringometaplasia was proposed for this unusual histologic finding. Mucinous and ciliated adenomatous syringometaplasia not only expands the spectrum of metaplastic changes in sweat gland units, but also might represent the missing link in the histogenesis of a subset of cutaneous ciliated cysts.

Mucinous Syringometaplasia: Surrounding Acanthosis With Hyperkeratosis Tends to Conceal the Change

A 57-year-old man had a 2-year history of a painful nodule on the right sole. Physical examination revealed an 8 × 8 mm hyperkeratotic plaque with a central fissure. Excisional biopsy disclosed epithelial invagination surrounded by the acanthotic epidermis with parakeratotic hyperkeratosis and focal hypergranulosis. The invaginated epithelium lacked a cornified layer and was composed of a mixture of small basaloid squamous cells and goblet cells showing tubular structures. The patient was diagnosed with mucinous syringometaplasia. Our literature review established that surrounding acanthosis with hyperkeratosis typically tends to conceal mucinous syringometaplastic changes. Because mucinous syringometaplasia often presents as an asymptomatic papule/nodule with no distinct ulcer, fissure, or depressed area, cases may be overlooked.

Primary cutaneous solitary fibrous tumor with entrapped eccrine components

First described in the pleura, solitary fibrous tumor (SFT) was subsequently reported in a variety of organ systems. Compared to other anatomic sites, primary cutaneous and superficial SFTs are relatively rare. Although several histopathologic variants of cutaneous and superficial SFT have been described, a primary cutaneous SFT harboring glandular components has not hitherto been documented in the literature. The current case report describes a spindle cell neoplasm of the right finger in a female patient with characteristic morphologic and immunohistochemical features of a SFT. Unexpectedly, various glandular and ductal components were identified in the SFT. A few hyperplastic lobules of sweat glands demonstrating similar morphology as the intratumoral glandular components and composed of secretory coils displaying mucinous metaplasia and ducts were detected in the attached subcutaneous tissue, suggestive of an inductive or obstructive effect of the SFT on the eccrine units. The intratumoral glands and ducts were judged to represent entrapped benign eccrine components from the attached subcutaneous tissue. Since this variant of SFT with entrapped eccrine components could mimic many biphasic epithelial and stromal tumors, pathologists should be aware of this unusual variant of SFT to avoid potential erroneous diagnosis, particularly mistaken confusion with a biphasic synovial sarcoma.

Adverse cutaneous reactions to chemotherapeutic drugs

Drug reactions resulting from chemotherapy agents are common and frequently affect the skin. Although often benign, a select few of these cutaneous reactions may necessitate immediate changes to the antineoplastic regimens. Given the diversity of chemotherapeutic skin reactions and their complex implications on patient management, an organized conceptual schema is imperative for proper patient care. We evaluate a number of commonly seen chemotherapy-induced skin toxicities organized by pathogenic mechanism and drug class, providing a framework for the identification and categorization of adverse events to prevent unrecognition. Groupings of these reactions include direct cytotoxicity and/or drug accumulation, immunologic hypersensitivity, and aberrant molecular signaling.

Eccrine duct dilatation in neutrophilic scarring alopecias

BACKGROUND

Eccrine duct dilatation (EDD) has been noted to occur significantly more often in primary lymphocytic scarring alopecias compared with non-scarring alopecias, thus serving as a possible histopathologic marker for primary scarring alopecias with a lymphocytic infiltrate. This study aims to determine the presence and role of EDD in primary neutrophilic scarring alopecias.

METHODS

We performed a retrospective review comparing primary scarring alopecia (neutrophilic, n = 90; lymphocytic, n = 100) and non-scarring alopecia (n = 123) for presence of EDD, seen in Boston University School of Medicine between 2013 and 2017.

RESULTS

EDD was more commonly seen in primary neutrophilic scarring (62.2%, 56/90) and primary lymphocytic scarring alopecias (54.0%, 54/100) than in non-scarring alopecias (25.2%, 31/123) (P < 0.001). Albeit uncommon, non-scarring alopecias exhibited the biggest ratio of dilated eccrine duct lumen to background duct lumen (14.33), followed by lymphocytic (10.99) and neutrophilic scarring alopecias (6.66).

CONCLUSION

EDD is seen more frequently in primary scarring alopecias compared with non-scarring alopecias and usually found in sections containing inflammation and dermal fibrosis, serving as a possible histopathologic clue for a scarring process. Non-scarring alopecias have significantly fewer but considerably larger EDD which, may imply a different pathologic cause.

Chemotherapy-induced eccrine squamous syringometaplasia in an infant

There are few reports of chemotherapy-induced eccrine squamous syringometaplasia in children. We report the first case of an infant developing this condition after treatment with busulfan, fludarabine, and antithymocyte globulin in preparation for bone marrow transplantation. Twenty-eight days after transplantation, the infant developed faintly erythematous papules and plaques on the bilateral axillae, inguinal folds, and sites of adhesives. Punch biopsy revealed eccrine glands with dyskeratotic cells and focal squamous metaplasia consistent with chemotherapy-induced eccrine squamous syringometaplasia.

Eruptive Multifocal Cutaneous Mucinous Cysts

Cutaneous cysts lined by mucinous epithelium are rare entities. We report an unusual case of a 60-year-old female patient who presented with a 2-month history of eruptive cystic papules on her right thigh. Histopathologic study showed multiple, multiloculated cysts located in the dermis lined by nonciliated mucinous epithelium. The cyst lining was positive for AE1/AE3, CK7, CK20, and GCDFP15. Patchy positivity was noted on the p53 stain. Attenuated Sox10 positive cells were identified, raising the possibility of sweat duct origin; however, no myoepithelial layer was identified by p63 staining. Mullerian markers, including ER, PR, WT1, and Pax8, were negative. We propose this as a unique case that may represent mucinous metaplasia of a cystic sweat duct lesion. Here, we review the literature of mucinous and other glandular cutaneous cysts.