Cutaneous plasmacytosis: an unusual presentation sharing features with POEMS syndrome?

Cutaneous plasmacytosis is a recently described skin disorder consisting of brown to red papules and nodules containing polyclonal plasmacytes. In this particular case, leg ulcers developed but also a diffuse patchy hyperpigmentation coexisting with a primary hypothyroidisim. The last two signs have only been described to date in POEMS syndrome, which is linked to monoclonal plasmacytic proliferation, and might suggest an overlap between these two entities.     

Interstitial granulomatous dermatitis? An unusual presentation in the mucosa and periungual skin

Interstitial granulomatous dermatitis (IGD) is a reactive phenomenon accompanying disorders including autoimmune disease, lymphoproliferative disorders and drug reactions. Histologically, IGD shows a granulomatous infiltrate surrounding piecemeal fragmentation of collagen in the diffuse interstitium. IGD presents with linear cords, papules and plaques mainly on the trunk and extremities. Herein, we report a case with peculiar clinical features that were histopathologically consistent with IGD. A 74-year-old man presented with periungual painful erythema, nail deformity of all fingers and labial, penile and anal erosive erythema. Histopathological examination of the lesions showed interface dermatitis and a diffuse interstitial granulomatous infiltrate mainly composed of CD68-positive histiocytes and lymphocytes. Degenerative collagen bundles were also observed in granulomas. C-reactive protein and the white blood cell count were elevated, but further examinations did not reveal systemic inflammatory disorders such as autoimmune disease, lymphoproliferative disorder, inflammatory bowel disease or drug hypersensitivity. The lesions were successfully treated with oral and topical steroids.     

Mycosis fungoides/Sézary syndrome: report of an unusual case

Introduction: Sézary syndrome (SS) is an uncommon form of cutaneous T cell lymphoma (CTCL) with a classical triad of lymphadenopathy, characteristic circulating lymphoma cells (Sézary cells) and erythrodermatous skin involvement with classical mycosis fungoides (MF)‐like histological picture. Case report: A 32‐year‐old woman presented with this classical triad; however, her skin involvement, histologically, was in the form of folliculotropic MF, rather than the usual classical form of MF. Conclusions: In the vast majority of cases, the cutaneous involvement in SS resembles conventional MF, histologically. One case of CD30‐positive CTCL with pilotropic MF has been reported. However, English literature does not describe any case of SS with folliculotropic MF with typical immunophenotype of SS thus far. We presume that this case represents the first report of SS with folliculotropic MF histologically, displaying the typical CD30‐negative immunophenotype.     

Congenital spindle cell naevus with unusual transformation: proliferative nodule or melanoma?

Congenital melanocytic naevi can give rise to secondary melanocytic tumours, such as proliferative nodules and malignant melanoma. The clinical and histological features of both lesions may be nearly identical, which makes an unequivocal diagnosis impossible. In particular, it is difficult to differentiate clearly between benign and malignant proliferation in infants with secondary melanocytic proliferation. Reports on melanocytic proliferation and malignant melanoma within the paediatric age-group are very rare. There is limited expert knowledge on this subject and little is known about prognosis and outcome. We report here a case of an infant with an unusual transformation of a congenital spindle cell naevus of the umbilical region, and discuss clinical, histological and genomic criteria.     

An unusual histopathologic feature of angiomatoid fibrous histiocytoma – A case report and molecular study

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumor with intermediate malignant potential. It predominantly affects children and young adults and is most often located in the extremities. The atypical pattern of AFH may create significant diagnostic difficulty. We present a case of AFH diagnosed via molecular confirmation by fluorescence in situ hybridization (FISH) and also review cases of AFH with atypical histologic presentations in Taiwan. We present this case to remind clinicians that identification of gene fusions by molecular testing is a valuable diagnostic tool for AFHs, especially in cases with atypical histopathological presentations.     

Primary localized cutaneous amyloidosis with unusual clinical features in a patient with Sjögren's syndrome

A 69‐year‐old woman presented with a 2‐year history of an eczematous lesion covering the genital area. Histopathological examination showed deposits of amorphous, eosinophilic material and an infiltrate of plasma cells through the entire dermis into the subcutaneous fatty tissue. Congo red‐stained deposits showed apple‐green birefringence with polarizing microscopy. On immunohistochemistry, the deposited material was positively stained with anti‐κ light chain antibodies but not with anti‐λ light chain. A diagnosis of primary localized cutaneous amyloidosis (PLCA) was made, and the patient was also diagnosed as having Sjögren's syndrome (SjS) based on clinical and laboratory findings. The lesion of PLCA has spontaneously regressed over a period of 18 months. We report a unique case of PLCA and SjS that clinically demonstrated genital eczematous features and spontaneous involution, and we also describe a possible association between PLCA and SjS.     

Adult T-cell leukemia/lymphoma with follicular mucinosis: an unusual histopathological finding and a commentary

Follicular mucinosis is currently recognized as a histopathological finding characterized by the accumulation of mucin within follicular epithelium and is commonly associated with follicular mycosis fungoides (MF). We report the finding of follicular mucinosis in a cutaneous nodule of human T-lymphotropic virus type 1 (HTLV-1) associated adult T-cell leukemia/lymphoma (ATLL). The patient was a 69-year-old female of Caribbean descent with a history of ATLL who presented with erythematous nodules on the chest and abdomen. Histopathologic examination showed a pan-dermal infiltrate of medium-to-large sized atypical lymphocytes extending into follicular epithelium where they associated with large mucin deposits. Immunohistochemical stains showed that the atypical lymphocytes were positive for CD3, CD4 and CD25 and negative for CD30. Cutaneous lesions of ATLL, which often present histopathologically as an epidermotropic lymphoma with Pautrier-type collections, are often difficult to distinguish from MF. Until recently, lymphoma-associated follicular mucinosis seemed specific to MF and Sézary syndrome (SS), being reported only once in a lesion of ATLL. We report a second case of ATLL-associated follicular mucinosis to increase awareness of this possible association, and briefly review the literature of follicular mucinosis-associated hematologic malignancies, ultimately cautioning against the interpretation of all cutaneous lymphoma-related follicular mucinosis as MF/SS.     

Extensive speckled lentiginous nevus associated with giant congenital melanocytic nevus: an unusual example of twin spotting?

A 15-year-old boy had an unusual combination of giant congenital melanocytic nevus on his back and a large speckled lentiginous nevus arranged in a checkerboard pattern on the dorsal and lateral aspects of his trunk. The two pigmentary nevi showed distinguishing features both clinically and histopathologically. The speckled lentiginous nevus was not noted at birth but became visible during childhood. We hypothesize that this uncommon co-occurrence may represent a further example of twin spotting and may be categorized as a new, distinct type of phacomatosis.