Diagnosis of bone marrow involvement in angioimmunoblastic T-cell lymphoma should be based on both [18F]FDG-PET/CT and bone marrow biopsy findings.

OBJECTIVE: During the initial staging of certain lymphoma subtypes, 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG-PET/CT) has become an alternative to bone marrow biopsy (BMB) for detecting bone marrow (BM) involvement. However, whether [18F]FDG-PET/CT can accurately detect BM involvement in angioimmunoblastic T-cell lymphoma (AITL) remains unknown. Our study aimed to assess the diagnostic and prognostic capability of [18F]FDG-PET/CT for detecting BM involvement in AITL. Methods: This retrospective study included 84 individuals newly diagnosed with AITL who underwent baseline BMB and [18F]FDG-PET/CT. "BM involvement" was defined as one or both of the following: 1) angioimmunoblastic T-cells detected in the BM; or 2) initially heightened focal uptake having disappeared on follow-up [18F]FDG-PET/CT. The ability of [18F]FDG-PET/CT to detect BM cancerous lesions was respectively analyzed by BM involvement confirmed by BMB or the aforementioned definition as the reference standard. The patients' clinical characteristics and survival and prognostic outcomes were respectively analyzed. RESULTS: Of the 84 participants, five (6.0%) displayed positive BMB and PET/BM results, 17 (20.2%) had BMB-positive but PET/BM-negative results, eight (9.5%) showed BMB-negative but PET/BM-positive outcomes, and 54 (64.3%) displayed negative BMB and PET/BM outcomes. Using pre-defined BM involvement as the reference standard, [18F]FDG-PET/CT exhibited a specificity of 100%, sensitivity of 40%, negative predictive value (NPV) of 75%, and positive predictive value (PPV) of 100%. In contrast, using BMB-detected BM involvement as reference, [18F]FDG-PET/CT exhibited a sensitivity, specificity, PPV, and NPV of 38.5%, 76.1%, 22.7%, and 87.1%, respectively. Among patients with PET/BM-positive and BMB-negative outcomes, 62.5% (5/8) underwent upstaging from III to IV. In 58.8% (10/17) of patients who were initially diagnosed with stage II/III disease based on the [18F]FDG-PET/CT results, repeat BMB resulted in upstaging to IV. PET/BM-negative patients had a higher 3-year progression-free survival rate (38.3% vs. 22.8%, p = 0.018) and 3-year overall survival rate (64.4% vs. 34.6%, p = 0.011) than PET/BM-positive patients. CONCLUSION: In AITL patients, PET/BM-positive results may obviate the necessity for repeat BMB to ascertain confirm BM involvement. PET/BM-negative results do not definitively exclude BM involvement. The combined use of [18F]FDG-PET/CT and BMB can increase the diagnostic accuracy of BM involvement for AITL patients.

Predicting T-Cell Lymphoma in Children From 18F-FDG PET-CT Imaging With Multiple Machine Learning Models.

This study aimed to examine the feasibility of utilizing radiomics models derived from 18F-FDG PET/CT imaging to screen for T-cell lymphoma in children with lymphoma. All patients had undergone 18F-FDG PET/CT scans. Lesions were extracted from PET/CT and randomly divided into training and validation sets. Two different types of models were constructed as follows: features that are extracted from standardized uptake values (SUV)-associated parameters, and CT images were used to build SUV/CT-based model. Features that are derived from PET and CT images were used to build PET/CT-based model. Logistic regression (LR), linear support vector machine, support vector machine with the radial basis function kernel, neural networks, and adaptive boosting were performed as classifiers in each model. In the training sets, 77 patients, and 247 lesions were selected for building the models. In the validation sets, PET/CT-based model demonstrated better performance than that of SUV/CT-based model in the prediction of T-cell lymphoma. LR showed highest accuracy with 0.779 [0.697, 0.860], area under the receiver operating characteristic curve (AUC) with 0.863 [0.762, 0.963], and preferable goodness-of-fit in PET/CT-based model at the patient level. LR also showed best performance with accuracy of 0.838 [0.741, 0.936], AUC of 0.907 [0.839, 0.976], and preferable goodness-of-fit in PET/CT-based model at the lesion level. 18F-FDG PET/CT-based radiomics models with different machine learning classifiers were able to screen T-cell lymphoma in children with high accuracy, AUC, and preferable goodness-of-fit, providing incremental value compared with SUV-associated features.

Nerve biopsy in T-cell lymphoma with neurolymphomatosis: where and when.

Peripheral T-cell lymphomas are rare heterogeneous haematological malignancies that may also involve peripheral nerves in a very small subset of cases. We report a patient with a diagnostically challenging cutaneous T-cell lymphoma and multifocal mononeuropathies in whom a targeted nerve biopsy identified lymphomatous infiltration of nerves and expedited combination treatment with chemotherapy and an autologous stem cell transplant. She showed an excellent response with a complete metabolic response on positron emission tomography imaging and significant clinical improvement, maintained 5 years post-treatment.

Utility of 18F-FDG PET/CT for differential diagnosis between IgG4-related lymphadenopathy and angioimmunoblastic T-cell lymphoma.

AIM: To explore the utility of the 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in the differential diagnosis of IgG4-related lymphadenopathy (IgG4-RLAD) and angioimmunoblastic T-cell lymphoma (AITL). MATERIALS AND METHODS: Retrospective analysis of 18F-FDG PET/CT imaging findings in clinically diagnosed IgG4-RLAD and AITL cases was undertaken to record the distribution, morphological characteristics, and imaging features of the affected lymph nodes, as well as FDG uptake of the spleen and bone marrow. Standardised uptake values normalised to lean body mass were evaluated for maximum (SULmax), average (SULavg), and peak values (SULpeak). Univariate and multivariate logistic regression was used to screen for statistically significant imaging findings to discriminate IgG4-RLAD from AITL. RESULTS: Twenty-two cases of IgG4-RLAD (17 men, five women, median age 49.5 years) and 22 cases of AITL (16 men, six women, median age 55 years) were finally included in the analysis. There were no AITL patients with involvement of a single lymph node region. AITL patients had more involvement of the different nodal regions except cervical and pelvic nodal regions. A practical assessment method based on a combination of SULpeak-LN/SULavg-liver, SULpeak-spleen, and the number of involved nodal regions, improved the performance for differential diagnosis between both groups with an overall classification accuracy of 90.9%. CONCLUSIONS: 18F-FDG PET/CT is a useful tool for distinguishing AITL from IgG4-RLAD, and it can also help determine the optimal biopsy site for suspected cases of IgG4-RLAD or AITL, reduce the need for re-biopsy procedures, and enable physicians to develop timely treatment strategies.

Extensive involvement of indolent T-cell lymphoma in a patient with ulcerative colitis.

Indolent T-cell lymphoma is a rare disease. Here we presented a 53-year-old male patient initially diagnosed as ulcerative colitis in 2000 that finally developed into extensive indolent T-cell lymphoma in 2022. We also described the differences between indolent T-cell lymphoma and inflammatory bowel disease, and the possible disease progression into lymphoma after biological therapy.

Extensive involvement of indolent T-cell lymphoma in a patient with ulcerative colitis

Indolent T-cell lymphoma is a rare disease. Here we presented a 53-year-old male patient initially diagnosed as ulcerative colitis in 2000 that finally developed into extensive indolent T-cell lymphoma in 2022. We also described the differences between indolent T-cell lymphoma and inflammatory bowel disease, and the possible disease progression into lymphoma after biological therapy. (AU)

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.

The pathophysiology and current treatments for the subcutaneous panniculitis-like T cell lymphoma: An updated review.

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a rare cutaneous T cell lymphoma, which is indolent in nature but could claim life if not correctly diagnosed and promptly treated. SPTCL is usually presented clinically as painless subcutaneous and erythematous nodules over the trunk or extremities. Active clinical vigilance for these subcutaneous nodules or panniculitis-like lesions is warranted. A biopsy must be performed in order to make a correct diagnosis. Positron emission tomography scan is utilized for disease staging and treatment follow-up. Due to the rarity of this lymphoma, a standard treatment protocol is not established yet. However, most cases of SPTCL could be treated well under immunosuppressive or polychemotherapeutic drugs except in cases with hemophagocytic syndrome. Hematopoietic stem cell transplantation may be used in refractory or relapse cases. In this review, we presented a case of SPTCL with long-term complete remission. Meanwhile, since most clinical evidences and experiences of SPTCL are based mostly on case reports or small case series, and the understanding of the SPTCL pathophysiology is limited, we reviewed and updated the pathophysiology and treatments of 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.

T-cell-lymphoma presented as a solitary subcutaneous mass in the ventral cervical region of an adult llama- diagnostic and treatment.

BACKGROUND: Neoplasm in South American camelids (SAC) are commonly described. The most frequently reported type of neoplasm are lymphomas and difference in the age suffering from lymphomas of and llamas is seen. This report describes a case of a solitary lymphoma in a 5 years and 9 month old llama mare displaying the approach of diagnostic imaging and successful surgical treatment. CASE PRESENTATION: The llama was referred to the clinic for dyspnoea and inspiratory abnormal respiratory sounds. The clinical examination comprised blood cell count, ultrasonographic and radiographic examinations, endoscopy and fine needle aspiration cytology of a mass detected in the mid cervical region. The mass was surgically removed. Histopathological examination of the surgically removed mass diagnosed a malignant T-cell- lymphoma. According to the results of the clinical, ultrasonographic and radiographic examinations no tumor invasion was apparent in distant organs and the llama was discharged from the clinic seven days after surgery. CONCLUSION: Lymphoma has been reported to be the most common neoplasia in camelids and are more often described in young alpacas and in adult llamas. To the author´s knowledge the case presented here is the first that described a broad panel of diagnostic tools including ultrasound, radiographs, endoscopy, fine needle aspiration cytology and histopathoogical examination as well as a successful surgical treatment of a solitary lymphoma in camelids.

Clinical, laboratory and ultrasonographic findings differentiating low-grade intestinal T-cell lymphoma from lymphoplasmacytic enteritis in cats.

BACKGROUND: Low-grade intestinal T-cell lymphoma (LGITL) is the most common intestinal neoplasm in cats. Differentiating LGITL from lymphoplasmacytic enteritis (LPE) is challenging because clinical signs, laboratory results, diagnostic imaging findings, histology, immunohistochemistry, and clonality features may overlap. OBJECTIVES: To evaluate possible discriminatory clinical, laboratory and ultrasonographic features to differentiate LGITL from LPE. ANIMALS: Twenty-two cats diagnosed with LGITL and 22 cats with LPE based upon histology, immunohistochemistry, and lymphoid clonality. METHODS: Prospective, cohort study. Cats presented with clinical signs consistent with LGITL or LPE were enrolled prospectively. All data contributing to the diagnostic evaluation was recorded. RESULTS: A 3-variable model (P < .001) consisting of male sex (P = .01), duration of clinical signs (P = .01), and polyphagia (P = .03) and a 2-variable model (P < .001) including a rounded jejunal lymph node (P < .001) and ultrasonographic abdominal effusion (P = .04) were both helpful to differentiate LGITL from LPE. CONCLUSIONS AND CLINICAL IMPORTANCE: Most clinical signs and laboratory results are similar between cats diagnosed with LGITL and LPE. However, male sex, a longer duration of clinical signs and polyphagia might help clinicians distinguish LGITL from LPE. On ultrasonography, a rounded jejunal lymph node, and the presence of (albeit small volume) abdominal effusion tended to be more prevalent in cats with LGITL. However, a definitive diagnosis requires comprehensive histopathologic and phenotypic assessment.

The value of complete remission according to positron emission tomography prior to autologous stem cell transplantation in lymphoma: a population-based study showing improved outcome.

BACKGROUND: Chimeric antigen-receptor T-cell and bispecific antibody therapies will likely necessitate a reconsideration of the role of autologous stem-cell transplantation (ASCT) in lymphoma. Patients who are likely to profit from ASCT need to be better identified. METHODS: Here, we investigated the value of positron emission tomography/computerized tomography (PET/CT) before ASCT. All 521 patients transplanted for lymphoma 1994-2019 at Karolinska (497 conditioned with BEAM) were included. RESULTS: Outcome improved over three calendar periods 1994-2004, 2005-2014, 2015-2019 (2-year overall survival [OS]: 66, 73, 83%; P = 0.018). Non-relapse mortality (NRM) at 100 days over the three periods were 9.8, 3.9, 2.9%, respectively. The OS improvement between 1994 and 2004 and 2005-2014 was due to lower NRM (P = 0.027), but the large OS advance from 2015 was not accompanied by a significant reduction in NRM (P = 0.6). The fraction of PET/CT as pre-ASCT assessment also increased over time: 1994-2004, 2%; 2005-2014, 24%; 2015-2019, 60% (P < 0.00005). Complete responses (PET/CT-CR) were observed in 77% and metabolically active partial responses (PET/CT-PR) in 23%. PET/CT-CR was a predictor for survival in the entire population (P = 0.0003), also in the subpopulations of aggressive B-cell (P = 0.004) and peripheral T-cell (P = 0.024) lymphomas. Two-year OS and progression-free survival (OS/PFS) for patients in PET/CT-CR were in relapsed/refractory aggressive B-cell lymphoma 87%/75% and peripheral T-cell lymphoma 91%/78%. The corresponding figures in PET/CT-PR were 43%/44 and 33%/33%. Patients with solitary PET/CT-positive lesions showed acceptable outcome with ASCT followed by local irradiation (2-year OS/PFS 80%/60%). CT was less discriminative: 2-year OS/PFS: CT-CR, 76%/66%; CT-PR, 62%/51%. Outcome was inferior after BEAC compared with BEAM conditioning. CONCLUSIONS: We conclude that the improved outcome reflects better, PET/CT-informed, identification of patients who should proceed to ASCT. The excellent survival of patients in PET/CT-CR indicates that ASCT should remain part of standard therapy for lymphoma.

Linfoma pericárdico primario a células T/NK: reporte de un caso / Primary pericardial T/NK cell lymphoma: case report / Linfoma pericárdico primário de células T/NK: relato de um caso

Los linfomas cardíacos primarios son un subtipo muy poco frecuente de tumor en los cuales la lesión primaria se encuentra en el corazón. Los tumores suelen ser infiltrantes y se localizan en la aurícula derecha, seguidos del pericardio. Su mortalidad es notablemente alta y el diagnóstico tardío es el principal factor para su mal pronóstico. Describimos el caso de un paciente que presentó shock obstructivo por derrame pericárdico profuso causado por un tipo raro de tumor cardíaco primario, un linfoma pericárdico de células T/NK.

Primary cardiac lymphomas are a rare subtype of lymphomas in which the primary lesion is in the heart. The tumors are usually located in the right atria, followed by the pericardium and are frequently infiltrative. Mortality is remarkably high in this group and the delayed diagnosis is the main factor for its poor prognosis. We describe the case of a patient that presented with obstructive shock due to profuse pericardial effuse caused by a rare kind of primary cardiac tumor, a T/NK cell pericardial lymphoma.

Os linfomas cardíacos primários são um subtipo de tumor muito raro, no qual a lesão primária está no coração. Os tumores geralmente são infiltrativos e localizam-se no átrio direito, seguidos pelo pericárdio. Sua mortalidade é notavelmente alta e o diagnóstico tardio é o principal fator que produz seu mau prognóstico. Descrevemos o caso de um paciente que apresentou choque obstrutivo devido a um derrame pericárdico profuso causado por um tipo raro de tumor cardíaco primário, um linfoma pericárdico de células T/NK.

Angioimmunoblastic T-cell lymphoma masquerading as granulomatous lymphadenitis: Fine needle aspiration cytology, clinical and radiology correlation.

Fine needle aspiration (FNA) is a minimally invasive technique used in the initial diagnosis of superficial lesions, including lymphadenopathy. Its benefit in lymph node pathology, however, is highly variable, especially in heterogeneous lymphoproliferative disorders like angioimmunoblastic T-cell lymphoma (AITL). AITL is an aggressive hematopoietic malignancy, histologically characterized by medium-sized neoplastic cells, high endothelial venule proliferations, and a heterogeneous hematolymphoid background. Diagnostic difficulty arises at lymph node FNA, where cytology yields nonspecific polymorphous collections of medium-sized lymphocytes, hematolymphoid cells, dendritic cell-lymphoid complexes, and lymphoid tissue fragments with transgressing blood vessels; findings mimicking reactive lymphadenopathy. We present a case of a 62-year-old male who presented with cervical lymphadenopathy. Neck level II lymph node FNA revealed granulomatous inflammation. A cell block was prepared for additional infectious studies but was non-contributory due to lack of material. Flow cytometry showed no evidence of non-Hodgkin lymphoma. Excisional biopsy revealed lymph node effacement by a T-cell lymphoproliferative disorder consistent with AITL. This case contributes to the paucity of literature regarding the cytologic features of AITL observed at FNA, and becomes the premier case to emphasize the addition of granulomatous features. Despite the aggressive nature of this entity, cases are frequently misdiagnosed as reactive on initial evaluation resulting in delay of treatment. This report serves to raise suspicion of AITL and other polymorphic cellular lymphomas in the setting of reactive granulomatous cytomorphology, thus prompting histological examination of tissue biopsy, expediting treatment, and ultimately providing potential improvement to the current prognosis.

IMMUNE RECOVERY UVEITIS-LIKE SYNDROME MIMICKING RECURRENT T-CELL LYMPHOMA AFTER AUTOLOGOUS BONE MARROW TRANSPLANT.

PURPOSE: To report the multimodal imaging findings of immune recovery uveitis mimicking recurrent T-cell lymphoma after autologous bone marrow transplant therapy. METHODS: A 71-year-old man presented with posterior uveitis 6 weeks after chemotherapy and autologous bone marrow transplant for angioimmunoblastic T-cell lymphoma. Multimodal imaging included fluorescein angiography, fundus autofluorescence, and optical coherence tomography. Diagnostic testing included ocular polymerase chain reaction and diagnostic vitrectomy. RESULTS: Clinical examination demonstrated vitritis and perivascular deep retinal whitening. Imaging of the retinal whitening showed late hyperfluorescence on fluorescein angiography, hyperautofluorescence on fundus autofluorescence, and ellipsoid zone loss on optical coherence tomography without infiltrative lesions. Testing was negative for syphilis, herpes simplex virus, varicella-zoster virus, and cytomegalovirus. After no clinical improvement with valacyclovir and intravitreal foscarnet treatment, diagnostic vitrectomy was performed. Bacterial and fungal cultures were negative, and herpes simplex virus, varicella-zoster virus, and cytomegalovirus were not detected by polymerase chain reaction. Cytopathology showed mature small nonneoplastic lymphocytes, macrophages, and monocytes. Flow cytometry demonstrated a reactive T-cell population. The patient demonstrated clinical improvement over time with spontaneous resolution of all retinal findings. CONCLUSION: This case most likely represents immune recovery uveitis-like syndrome. Diagnostic vitrectomy is highly valuable when the differential includes inflammatory, infectious, and neoplastic processes.