Mantle cell lymphoma (MCL) is a rare and heterogeneous subtype of B-cell non-Hodgkin lymphoma (NHL), defined by the t(11;14)(q13;q32) translocation leading to overexpression of cyclin D1. The blastoid variant represents a highly aggressive form, with a high mitotic index and unfavorable prognosis. Cutaneous involvement by mantle cell lymphoma is rare and may present with atypical clinical features, often leading to delayed diagnosis due to morphological overlap with other high-grade lymphomas and unusual extranodal presentations. We describe a 73-year-old male who presented with a solitary fluctuant swelling over the left cervical region clinically suspected to represent an abscess, without systemic symptoms or lymphadenopathy. Contrast-enhanced imaging revealed a localized lesion without additional lymphadenopathy. Histopathological examination of a core biopsy demonstrated medium to large atypical lymphoid cells. Immunohistochemistry showed strong expression of CD20, CD5, cyclin D1, SOX11, and a high Ki-67 proliferation index (~90%-95%), supporting a diagnosis of blastoid variant MCL. These cells were immunonegative for CD3, CD10, BCL6, and CD30, excluding other high-grade lymphomas. This case highlights an unusual presentation of blastoid mantle cell lymphoma, manifesting as an abscess-like cutaneous lesion of the neck and underscores the importance of histopathologic and immunophenotypic evaluation in atypical cutaneous swellings. Early recognition, facilitated by histopathological and immunophenotypic evaluation, is critical for initiating timely and appropriate treatment in such aggressive lymphomas.

Plasmablastic lymphoma (PBL) is a rare, high-grade large B-cell lymphoma characterized by large atypical cells with plasmablastic or immunoblastic morphology and a terminal B-cell differentiation phenotype. PBL often occurs in patients with immune deficiency or dysregulation, most commonly HIV infection. Cutaneous involvement is rare and occurs most frequently in those with immune deficiency. We report a 73-year-old immunocompetent female presenting with multiple cutaneous lesions and cervical lymphadenopathy. Nasopharyngeal and cutaneous biopsies confirmed EBV-associated PBL with plasmacytic differentiation, mimicking primary cutaneous marginal zone lymphoma (PC-MZL). The patient was treated with multiagent chemotherapy. Her disease progressed and she passed away in 9 months. We reviewed the literature for EBV-associated PBL occurring in the skin and those in immunocompetent patients. A comprehensive systemic evaluation integrating clinical, laboratory, and imaging findings is essential for excluding PC-MZL and plasmablastic multiple myeloma and establishing the correct diagnosis.

Intravenous immunoglobulin (IVIg) is the standard of care for the treatment of Kawasaki disease (KD) and should be administered within 10 days of the onset of fever. Management guidelines for children with KD who defervesce spontaneously are not clear. In this study, we analysed patients with KD diagnosed between 1994 and 2024 at our centre who had defervesced spontaneously, had normal acute-phase reactants, and underwent echocardiographic examination, and in whom IVIg had not been administered. We reviewed the records of patients with KD from January 1994 - December 2024. The diagnosis of KD was based on standard guidelines. Patients with KD were said to be in spontaneous defervescence when they remained afebrile for ≥ 48 h, had normal acute-phase reactants [C-reactive protein (CRP), Erythrocyte sedimentation rate (ESR)] and no coronary artery abnormalities (CAAs) on echocardiography at presentation, and when IVIg was not administered. Patients with spontaneous defervescence were subdivided into (i) early defervescence (Ed-KD), if the interval between onset of symptoms and defervescence was < 10 days, and (ii) late defervescence (Ld-KD), if the duration between onset of symptoms and defervescence was ≥ 10 days, respectively. Details of the clinical profile, laboratory investigations, and echocardiography findings were obtained from the records. Of the 1499 patients with KD enrolled during the study period, 115 patients (7.7%; 86 boys) defervesced spontaneously. The median age at disease onset was 6 years (mean, 5.6 years; range, 0.8-15 years). The median duration of fever, defined as the total duration of the febrile episode before spontaneous defervescence, was 5 days (range, 1-21 days). The median interval between illness onset (defined as fever onset) and diagnosis of KD was 15 days (range, 4-40 days), indicating that diagnosis was often made after fever had already subsided. The most common clinical feature was periungual desquamation, followed by rash, oral-mucosal changes, cervical lymphadenopathy, and conjunctival injection. Incomplete presentation was noted in 73.9% (n = 85/115) of patients. No patient has developed CAAs or other cardiac sequelae over a median follow-up of 9 months (range 2 months-156 months). The cumulative follow-up for the cohort was 235 patient-years. The 'low-risk' subgroup of patients with KD who defervesce spontaneously, and have normal acute phase reactants with no CAAs at presentation, have good clinical and coronary outcomes.

Carcinoma ex pleomorphic adenoma (Ca ex PA) is an uncommon but highly aggressive malignancy arising from long-standing pleomorphic adenoma. Malignant transformation typically presents with rapid enlargement, pain, and facial nerve involvement. Metastatic spread is exceptionally rare. We describe a 67-year-old man with a decades-long right parotid mass that underwent malignant change after prior surgical excision confirmed Ca ex PA. After being lost to follow-up, he re-presented with neck stiffness, hearing loss, and facial nerve palsy. Imaging demonstrated a recurrent parotid mass infiltrating adjacent space, accompanied by cervical lymphadenopathy and bilateral pulmonary nodules suggestive of metastases. This case highlights the severe consequences of untreated or inadequately followed salivary gland neoplasms and underscores the necessity of early excision, thorough histopathologic assessment, and consistent long-term surveillance to prevent advanced Ca ex PA.

Adult T-cell leukemia/lymphoma (ATLL) is a rare, human T-lymphotropic virus type 1 (HTLV-1)-driven neoplasm that is often underrecognized in low-endemic regions. We describe a 23-year-old man with an eight-year history of chronic dry cough who later developed weight loss, night sweats, odynophagia, and dyspnea. CT revealed cervical/supraclavicular lymphadenopathy with innumerable pulmonary micronodules, interlobular septal thickening, and ground-glass opacities; abdominal imaging showed hepatosplenomegaly, ascites, and extensive retroperitoneal/mesenteric adenopathy. HTLV-1 ELISA and confirmatory Western blot were positive. Excisional lymph node biopsy demonstrated diffuse architectural effacement by atypical T cells with a CD3+, CD4+, CD5+, CD25+, CD7-, granzyme B+ immunophenotype and a ~90% Ki-67 index, establishing lymphomatous-type ATLL with a cytotoxic profile. Despite rapid recognition, the patient deteriorated and died from respiratory failure 15 days after diagnosis, before chemotherapy could begin. This lung-predominant presentation in a young adult illustrates how ATLL can mimic chronic pulmonary disease and evade early detection outside endemic areas. Clinicians should prioritize early tissue acquisition and a minimal T-cell panel (CD3, CD4, CD25, CD7, Ki-67); a CD4+CD25+ phenotype with CD7 loss should prompt HTLV-1 testing irrespective of geography. Streamlined access to immunophenotyping and confirmatory HTLV-1 assays is essential to reduce diagnostic delays and improve outcomes.

Rosai-Dorfman disease is a rare reactive histiocytic proliferation disorder. It is rarely reported in the literature, and its clinical manifestations vary depending on the location of occurrence. The clinical manifestations and imaging features are not characteristic, and the diagnosis mainly relies on pathology and immunohistochemistry. Here, we report a case involving the nasal cavity and paranasal sinuses, which did not exhibit typical symptoms such as painless cervical lymphadenopathy and fever. It could easily have been misdiagnosed as a malignant tumor before surgery. This case did however exhibit typical histopathological features. The patient was treated with surgery combined with hormone therapy and a good clinical outcome was achieved.

Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a rare non-Langerhans cell histiocytic disorder most commonly involving the cervical lymph nodes, which are affected in approximately 80%-90% of cases. It predominantly affects children and young adults but may occur at any age, typically presenting with painless, bilateral, and sometimes bulky cervical lymphadenopathy, occasionally associated with systemic inflammatory symptoms and laboratory abnormalities such as elevated inflammatory markers and polyclonal hypergammaglobulinemia. Histopathological examination is essential for diagnosis and demonstrates marked sinus expansion by large histiocytes with abundant pale cytoplasm and characteristic emperipolesis, set within a lymphoplasmacytic background. Immunohistochemically, these histiocytes express CD68, CD163, and S100 protein, while lacking CD1a and langerin expression, allowing distinction from other histiocytic disorders. Although historically considered a benign reactive condition, recent molecular studies have identified activating mutations in the MAPK/ERK signaling pathway, including KRAS, NRAS, and MAP2K1, in a significant subset of cases, supporting a clonal neoplastic component. The clinical course of cervical RDD is generally favorable, and management is individualized, ranging from observation to surgical excision in cases of compressive symptoms, with systemic or targeted therapies reserved for refractory or multisystem disease. We report the case of a 25-year-old patient with no significant past medical history who presented with a persistent cervical lymphadenopathy. Comprehensive clinical evaluation, laboratory investigations, and imaging studies supported the diagnosis of Rosai-Dorfman disease. Prompt recognition and appropriate surgical management play a crucial role in achieving favorable clinical outcomes.