Remarkable FDG Uptake in Numerous Granulomatous Panniculitis Lesions: A Case Report.

ABSTRACT: A 42-year-old woman with history of rheumatoid arthritis and erythema nodosum from 8 years ago, who was treated with CellCept and prednisolone, was admitted to the rheumatology service due to skin lesions in the upper and lower extremities. Skin excisional biopsy was performed, and the results suggested panniculitis. FDG PET/CT was performed for malignancy workup. The scan images revealed intensely increased FDG uptake in all numerous subcutaneous nodules. FDG uptake in the panniculitis lesion is rarely reported in the literature.

Inverted FDG Uptake Pattern in Subcutaneous Panniculitis-Like T-Cell Lymphoma.

ABSTRACT: A 47-year-old woman presented with a 2-month history of subcutaneous nodules, erythema, and fever. 18F-FDG PET images demonstrated inverted FDG uptake pattern corresponding to the subcutaneous lesion against lymph nodes. The specimen of the inguinal lesion showed massive infiltration of small lymphocytes in the adipose tissue with rimming adipocytes, whereas very few tumor cells infiltrated the lymph nodes. Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) was diagnosed. SPTCL normally shows quite interesting distribution of tumor cells, that is, lymph node involvement is usually absent. Therefore, this case highlighted the importance of the inverted accumulation pattern on FDG PET to suspect SPTCL.

Role of PET imaging in peritoneal involvement of subcutaneous panniculitis-like T-cell lymphoma.

Subcutaneous panniculitis-like T-cell lymphoma is a rare subtype of cutaneous T-cell lymphomas and represents less than 1% of non-Hodgkin's lymphomas. Currently, the diagnosis is based on clinical and histological findings although clinical features may be nonspecific. Often, it is localised to subcutaneous tissue without lymph node involvement. The literature is sparse but unusual presentations have been described to involve mesentery, breast and even eyelids. Fluorine-18 fluorodeoxyglucose positron-emission tomography/computed tomography has been reported to be useful in assessing disease activity, extent and treatment response in subcutaneous panniculitis-like T-cell lymphoma but we find that it can also be a diagnostic aid for atypical presentations. In our case report, we describe a patient who presented with a neck lump but did not have any other obvious cutaneous lesions. This was biopsied and had histological features in keeping with subcutaneous panniculitis-like T-cell lymphoma. Due to the atypical presentation, positron-emission tomography was crucial for detecting the extracutaneous and likely primary site of disease in the peritoneum, which hence guided the subsequent biopsy to this affected area and confirmed the diagnosis.

BRAF inhibitor-induced panniculitis in patients treated for stage IV metastatic melanoma: a case series.

BRAF and MEK inhibitor combination therapy is the standard treatment for patients with BRAF V600E mutant metastatic melanoma. Neutrophilic panniculitis is a known rare complication of BRAF inhibitor therapy and can act as a potential mimic of melanoma metastases on 18F-FDG PET/CT. In this case series, we present three cases of BRAF inhibitor-induced panniculitis in patients being treated for BRAF-mutant metastatic melanoma and emphasize the use of ultrasound to differentiate between panniculitis lesions, which are typically ill-defined echogenic masses and subcutaneous soft tissue melanoma metastases, which present as hypoechoic vascular masses.

Familial aggregation of subcutaneous panniculitis-like T cell lymphoma: A case report of monozygotic twin brothers.

RATIONALE: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare subtype of cutaneous lymphoma, which was first defined as a clinical entity in 1991 as a cytotoxic T-cell lymphoma preferentially infiltrating subcutaneous tissue. Herein, we report 2 patients of SPTCL who are a pair of twin brothers. PATIENT CONCERNS: The disease afflicted the monozygotic twin brothers at different time with an interval period of 5 years. The older twin brother had disease onset at 27 years of age. In June 2012, he developed prolonged fever accompanied by subcutaneous nodules in the left upper arm and left chest due to unknown origin. The younger twin brother had disease onset at 32 years of age. In June 2017, the younger brother presented with repeated high fever for more than 10 days, accompanied by head distension. DIAGNOSIS: On August 7, 2012, skin biopsy was performed on the lesion of left upper arm of the older twin brother, and then, a diagnosis of subcutaneous panniculitis-like T cell lymphoma (SPTCL) was made. On June 19, 2017, the younger twin brother underwent whole-body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography for diagnosis. Soon afterwards, abdominal subcutaneous nodule resection and biopsy was performed on June 28, 2018, and the specimen was diagnosed as SPTCL. INTERVENTIONS: For the older brother, a total of 14 systemic chemotherapy sessions were performed from August 16, 2012, to September 21, 2014. For the younger brother, a total of 9 systemic chemotherapy sessions were performed from July 14, 2017, to March 8, 2018, then he was switched to oral chemotherapy with chidamide twice a week for 6 months. OUTCOMES: The older twin brother died in March 2015, the younger brother has recovered well and is no longer receiving any treatment LESSONS:: To the best of our knowledge, twin brothers both having this disease has never been previously reported. Moreover, some of the involved areas are also extremely rare detected by fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography at initial stage. It is beneficial to people to gain some new understanding for SPTCL by this special case and some extremely unusual involved sites in the younger twin brother.

18F-FDG PET/CT-Guided Diagnosis and Evaluation of Treatment Response to Cyclosporine A in Maldistributed Subcutaneous Panniculitis-like T-Cell Lymphoma Without Typical Skin Rash.

A 30-year-old woman presented with persistent fever and elevated lactate dehydrogenase levels without skin rash. F-FDG PET/CT revealed FDG uptake in subcutaneous tissues in the forearm, buttocks, and lower limbs, whereas the trunk was unaffected. She was diagnosed with subcutaneous panniculitis-like T-cell lymphoma based on a PET/CT-guided subcutaneous tissue biopsy from the thigh. Although conventional cytotoxic agent-based chemotherapies failed to achieve disease remission, subsequent cyclosporine A treatment promptly resolved the fever and laboratory abnormalities. Remarkably, abnormal FDG uptake disappeared entirely on follow-up PET/CT, demonstrating its utility in the evaluations of responses to emerging cyclosporine A-based treatments in subcutaneous panniculitis-like T-cell lymphoma.

Panitumumab Induced Forearm Panniculitis in Two Women With Metastatic Colon Cancer.

BACKGROUND: Panitumumab is an EGFR inhibitor used for the treatment of metastatic colorectal cancer (mCRC), even if its use is related to skin toxicity. CASE PRESENTATION: We report the development of forearm panniculitis in two women during the treatment with Panitumumab (6 mg/Kg intravenous every 2 weeks) + FOLFOX-6 (leucovorin, 5- fluorouracil, and oxaliplatin at higher dosage) for the treatment of mCRC. RESULTS: In both patients, clinical, laboratory and radiological evaluation documented the presence of a local panniculitis, probably related to panitumumab (Naranjo score: 6). Panatimumab discontinuation and antimicrobial + corticosteroid treatment induced a remission of skin manifestations. CONCLUSION: We reported for the first time the development of panniculitis during Panitumumab treatment, and we documented that the treatment with beta-lactams to either fluoroquinolones or oxazolidinone in the presence of corticosteroid improves clinical symptoms in young patients with mCRC, without the development of adverse drug reactions or drug-drug interactions.

Spred2 Regulates High Fat Diet-Induced Adipose Tissue Inflammation, and Metabolic Abnormalities in Mice.

Chronic low-grade inflammation in visceral adipose tissues triggers the development of obesity-related insulin resistance, leading to the metabolic syndrome, a serious health condition with higher risk of cardiovascular disease, diabetes, and stroke. In the present study, we investigated whether Sprouty-related EVH1-domain-containing protein 2 (Spred2), a negative regulator of the Ras/Raf/ERK/MAPK pathway, plays a role in the development of high fat diet (HFD)-induced obesity, adipose tissue inflammation, metabolic abnormalities, and insulin resistance. Spred2 knockout (KO) mice, fed with HFD, exhibited an augmented body weight gain, which was associated with enhanced adipocyte hypertrophy in mesenteric white adipose tissue (mWAT) and deteriorated dyslipidemia, compared with wild-type (WT) controls. The number of infiltrating macrophages with a M1 phenotype, and the crown-like structures, composed of macrophages surrounding dead or dying adipocytes, were more abundant in Spred2 KO-mWAT compared to in WT-mWAT. Exacerbated adipose tissue inflammation in Spred2 KO mice led to aggravated insulin resistance and fatty liver disease. To analyze the mechanism(s) that caused adipose tissue inflammation, cytokine response in mWAT was investigated. Stromal vascular fraction that contained macrophages from Spred2 KO-mWAT showed elevated levels of tumor necrosis factor α (TNFα) and monocyte chemoattractant protein-1 (MCP-1/CCL2) compared with those from WT-mWAT. Upon stimulation with palmitate acid (PA), bone marrow-derived macrophages (BMDMs) derived from Spred2 KO mice secreted higher levels of TNFα and MCP-1 than those from WT mice with enhanced ERK activation. U0126, a MEK inhibitor, reduced the PA-induced cytokine response. Taken together, these results suggested that Spred2, in macrophages, negatively regulates high fat diet-induced obesity, adipose tissue inflammation, metabolic abnormalities, and insulin resistance by inhibiting the ERK/MAPK pathway. Thus, Spred2 represents a potential therapeutic tool for the prevention of insulin resistance and resultant metabolic syndrome.

Relapsed subcutaneous panniculitis-like T cell lymphoma evaluated by FDG PET/CT: A clinical case report.

RATIONALE: Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a rare primary cutaneous T cell lymphomas expressing α/ß T cell receptors that preferentially involves subcutis, and few reports have investigated the diagnosis of suspicious relapsed SPTCL using F-fluoro-2-deoxy-D-glucose (F-FDG) positron emission tomography/computed tomography (PET/CT). PATIENT CONCERNS: A 15-year-old woman complaining of a growing painless subcutaneous mass on perinaeum recurred 2 months ago, suggestive of suspicious relapsed SPTCL, underwent FDG PET/CT for diagnosis and treatment follow-up. DIAGNOSIS: Based on the feature of FDG PET/CT images which revealed multiple increased FDG-avid subcutaneous adipose tissue lesions on the left upper arm, the left chest and perinaeum, involvement of bilateral inguinal lymph nodes, and the effective chemotherapy, she was diagnosed with relapsed SPTCL. INTERVENTIONS AND OUTCOMES: Fortunately, the patient's skin lesions subsided gradually after 3 cycles of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) regimen. Besides, complete remission was observed on interim-FDG PET/CT after 3 cycles of CHOP treatment. LESSONS: FDG PET/CT can clarify the diagnosis in suspicious relapsed SPTCL, avoiding performing skin biopsy again.

Subcutaneous panniculitis-like T-cell lymphoma: Clinical features, therapeutic approach, and outcome in a case series of 16 patients.

BACKGROUND: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare primary cutaneous lymphoma of mature cytotoxic T cells. Initially, patients with SPTCL were treated with doxorubicin-based polychemotherapy. OBJECTIVE: To analyze clinical, biologic, immunophenotypical, molecular, imaging, treatment, and outcome data reflecting the current state of knowledge. METHODS: A retrospective multicenter study of 16 patients with SPTCL that was diagnosed between 1996 and 2016. RESULTS: The female-to-male ratio was 1.7. The median age at diagnosis was 46.5 years. Patients presented with multiple nodular or plaque-like lesions preferentially affecting the legs and/or trunk. Histopathology typically showed a lobular panniculitis with individual adipocytes surrounded by atypical lymphocytes, usually with a CD3+, CD4-, CD8+, CD56-, TIA1 cytotoxic granule associated RNA binding protein 1-positive phenotype and high proliferation rate. SPTCL was associated with autoimmune diseases in 25% of patients, and with the development of hemophagocytic syndrome in 18% of patients. Oral steroids alone or in combination with low-dose methotrexate or cyclosporine A were the most common initial treatment, achieving a complete response in 85% of the treated patients. The median follow-up time was 14 months. The 5-year disease-specific survival rate was 85.7%. LIMITATIONS: This was a retrospective study. CONCLUSIONS: SPTCL has an excellent prognosis. Immunosuppressive agents can be considered for first-line treatment.

Nódulos subcutáneos faciales de 3 meses de evolución.

Siliconomas are subcutaneous nodules that usuallyappear as a consequence of the migration of freesilicon implanted in other locations. They are morefrequent in women with abnormal breast implants,such as poly implant prostheses (PIP), but they may alsoappear after illegal injection of free silicone. We reporta 57-year-old woman who attended our Dermatologyclinic complaining of relapsing facial panniculitis ofunknown origin. After a thorough work-up, thesenodules were determined to be the consequence ofdermal filler made with fluid silicone, which had beeninjected 20 years prior. High frequency skin ultrasoundof one of the nodules showed a hyperechoic image,also known as "snowstorm," which was located in thesubcutaneous tissue. The disposition of silicone in thisplane obscures the view of any sonographic structurein the underlying plane. Cutaneous sonographyhas become one of the most useful non-invasivetechniques in diagnosis of filler complications andother inflammatory diseases. Combined treatmentwith prednisone and allopurinol was successful, withno recurrence after 1 year of follow-up.