Characterization of T-cell lymphomas by FDG PET/CT. AJR Am J Roentgenol. 2010;195:333-340. [PMID: 20651187 DOI: 10.2214/ajr.09.3665]

Skin Malignancies: Imaging Review with Radiologic-Histopathologic Correlation

Skin malignancies are commonly encountered as primary or incidental findings. Neoplasms that affect the skin include primary (basal cell carcinoma, squamous cell carcinoma, melanoma, and Merkel cell carcinoma) and secondary (mesenchymal neoplasms, lymphoma, and metastases) tumors. Imaging provides valuable anatomic information (tumor size, depth of involvement, presence of distant metastasis, and data for guiding biopsy) and functional information (metabolic activity and sentinel node mapping data). This information, in addition to biopsy results, improves the histopathologic characterization of tumors and treatment planning. Various histopathologic types of the same entity exhibit different biologic behavior and have different imaging features. Familiarity with the multimodality imaging features, histopathologic characteristics, and various modes of dissemination (direct invasion; perineural, lymphatic, and hematogenous spread) of the most common skin malignancies helps radiologists narrow the differential diagnosis in clinical practice. ©RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Interesting Presentation of Mycosis Fungoides in Staging on F-18 FDG PET/CT

Mycosis fungoides is the major form of primary cutaneous T cell lymphoma. Its staging is based on the percentage of body surface involvement and biopsy-proven extra cutaneous nodal or visceral involvement. Literature shows F-18 FDG accumulation in disease-involved nodes and viscera with non-specific uptake due to co-existing inflammation limits its specificity. We report an interesting case of mycosis fungoides with bilateral upper limb edema and share its findings on F-18 FDG PET/CT.

Prognostic value of 18F-FDG lesion dissemination features in patients with peripheral T-cell lymphoma (PTCL)

PURPOSE

To explore the prognostic value of the distance between the two lesions that were farthest apart (Dmax) on baseline 18F-FDG PET/CT in peripheral T lymphoma (PTCL) and establish a new prognostic model for predicting the survival outcomes of patients with PTCL.

METHODS

In this study, a retrospective analysis of 95 patients with PTCL who underwent baseline 18F-FDG PET/CT was performed to assess the predictive value of Dmax. The total metabolic tumour volume (TMTV), total lesion glycolysis (TLG), standardized uptake value (SUV), and Dmax were calculated with LIFEx software. Progression-free survival (PFS) and overall survival (OS) were used as endpoints. The prognostic model was developed based on the results of the multivariate analysis. The time-dependent area under the ROC curve (tdAUC), calibration curves, Harrell C-index, and decision curve analysis (DCA) were used to assess the model.

RESULTS

Patients were followed up for a median of 17.0 months. Multivariate analysis showed that bone marrow biopsy (BMB) and Dmax were independent predictors of PFS (HR: 1.889, P = 0.039; HR: 1.965, P = 0.047) and OS (HR: 1.923, P = 0.031; HR: 1.982, P = 0.034). The model consisting of Dmax, TMTV, and BMB had substantial prognostic value for survival outcomes of PTCL and could successfully identify four groups of patients with significantly different prognoses (χ² = 13.731, P = 0.003 for PFS; χ² = 11.841, P = 0.008 for OS). The tdAUC, C-index, calibration curves, and DCA supported that the model was superior to the prognostic index for T-cell lymphoma (PIT) and International Prognostic Index (IPI) scores.

CONCLUSION

BMB and Dmax were independent predictors of PTCL in our study. Moreover, a prognostic model based on the Dmax, TMTV, and BMB could be useful for predicting the survival outcomes of patients with PTCL.

[18F]FDG PET/CT in a Case of Mycosis Fungoides Showing an Unusual Adverse Reaction to Mogamulizumab: Correlation Between Imaging and Histological Findings

A 73-year-old female patient, affected by mycosis fungoides (MF), discontinued mogamulizumab, after initial clinical benefit, due to the onset of generalized erythema. Follow-up positron emission computed tomography (PET/CTs) carried out at 3 weeks and 6 months after therapy discontinuation showed, with respect to baseline PET/CT scan, a progressively increasing number of hypermetabolic enlarged lymph nodes suspected for a neoplastic involvement, but with histology indicative of an inflammatory reaction. After sequential therapy with corticosteroids and methotrexate, a complete remission was registered at 18F-fluorodeoxyglucose ([¹⁸F]FDG) PET/CT performed at 12 months after mogamulizumab interruption. The case we describe highlights the usefulness of serial examinations with [¹⁸F]FDG PET/CT in an MF patient presenting an unusual adverse reaction to mogamulizumab.

Application of the Lugano Classification for Initial Evaluation, Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: The PRoLoG Consensus Initiative (Part 1-Clinical)

Our objective was to provide consensus recommendations from a consortium of academic and industry experts in the field of lymphoma and imaging for consistent application of the Lugano classification. Methods: Consensus was obtained through a series of meetings from July 2019 until September 2021 sponsored by the Pharma Imaging Network for Therapeutics and Diagnostics (PINTaD) as part of the PINTaD Response Criteria in Lymphoma Working Group (PRoLoG) consensus initiative. Results: Consensus recommendations clarified technical considerations for PET/CT and diagnostic CT from the Lugano classification, including updating the FDG avidity of different lymphoma entities, clarifying the response nomenclature, and refining lesion classification and scoring, especially with regard to scores 4 and 5 and the X category of the 5-point scale. Combination of metabolic and anatomic responses is clarified, as well as response assessment in cases of discordant or missing evaluations. Use of clinical data in the classification, especially the requirement for bone marrow assessment, is further updated on the basis of lymphoma entities. Clarification is provided with regard to spleen and liver measurements and evaluation, as well as nodal response. Conclusion: Consensus recommendations are made to comprehensively address areas of inconsistency and ambiguity in the classification encountered during response evaluation by end users, and such guidance should be used as a companion to the 2014 Lugano classification.

An Updated Approach and Understanding of Breast Implant-Associated Anaplastic Large Cell Lymphoma

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare subtype of T-cell non-Hodgkin lymphoma that is usually localized to the fluid and capsule surrounding a breast implant. There have only been <1,000 cases and 36 deaths reported to date and the average patient presents 7 to 10 years following initial breast implant placement. Most patients present with delayed seromas, a breast mass, capsular abnormalities, lymphadenopathy, or cutaneous masses. Unlike other forms of non-Hodgkin lymphoma, most cases are cured with surgery alone. The challenge of BIA-ALCL surrounds its rarity-in regard to both its diagnosis as well as the limited available data to guide therapy for more advanced cases. Careful pathology evaluation to analyze both the fluid surrounding the capsule and the capsule itself is critical. Studies to identify which patients are at greater risk of development of this rare entity are ongoing.

Angioimmunoblastic T-cell lymphoma: treatment strategies and prognostic factors from a retrospective multicenter study in China

Angioimmunoblastic T-cell lymphoma (AITL) is a unique sub-type of peripheral T-cell lymphoma (PTCL). We aimed to evaluate treatment programs and prognostic factors of 121 newly diagnosed patients with AITL in China from January 2001 to December 2018. The median age was 58 years with male predominance. Bone marrow involvement appeared in only 8.3% of patients, which was different from the previously published literature. The 5-year progression-free survival (PFS) and 5-year overall survival (OS) were 29.7% and 44.0%, respectively. Univariate and multivariate analyses showed that involvement of >5 nodal areas, age and Beta-2 microglubulin were highly predictive of OS but only the involvement of fewer than five nodal areas was significant for PFS. We identified a novel prognostic model including the three factors that may be applied in clinical practice and offer an alternative to IPI and PIT.

The role of pre-treatment and mid-treatment 18F-FDG PET/CT imaging in evaluating prognosis of peripheral T-cell lymphoma-not otherwise specified (PTCL-NOS)

BACKGROUND

It has been reported the prognostic value of MTV in predicting the disease prognosis of peripheral T-cell lymphoma (PTCL) through pre-treatment PET/CT imaging. However, these are limited data on pretreatment evaluation and prognosis assessments of peripheral T-cell lymphoma-not otherwise specified (PTCL-NOS). This study aimed to determine the prognostic values of pre-treatment and mid-treatment total metabolic tumor volume (MTV), total lesion glycolysis (TLG), and Deauville 5-Point Scale (D-5PS) in accessing the prognosis of PTCL-NOS.

METHODS

A retrospective analysis was conducted in 31 patients with pathologically diagnosed PTCL-NOS. These patients have undergone positron emission PET/CT scanning before and during chemotherapy. Follow-ups were also done to investigate the 2-year progression-free survival (PFS) and Overall Survival (OS) of these patients. During [Formula: see text]F-fluorodeoxyglucose ([Formula: see text]F-FDG) PET/CT scans, the MTV and TLG were recorded. Meanwhile, [Formula: see text]MTV and [Formula: see text]TLG were calculated. Furthermore, the receiver operating characteristic (ROC) curve was employed to classify and to define the threshold values. On the other hand, the mid-chemotherapy assessment and staging of these 31 patients were done by utilizing D-5PS. Subsequently, based on the D-5PS scores obtained, these patients were grouped into two categories: a group of patients with a score of <4 and another group with [Formula: see text]4 points. For these two groups of patients, the survival analysis was done by Kaplan-Meier analysis and a multivariate COX regression model. Moreover, Pearson's chi-square test ([Formula: see text] test) and Spearman rank correlation coefficient were used to comparing the collected data, respectively.

RESULTS

During the 2-year follow-up period, 15 out of the 31 patients experienced disease progression. The optimal threshold values for both baseline MTV and TLG were 158.16 cm[Formula: see text] and 677.40.Additionally, the difference in 2-year PFS between the progressive and non-progressive groups was statistically significant ([Formula: see text], [Formula: see text]; [Formula: see text], [Formula: see text]), significant between-group difference was detected for MTV and for TLG ([Formula: see text], [Formula: see text]; [Formula: see text], [Formula: see text]). On the other hand, when these patients were classified into two groups according to the mid-chemotherapy Deauville score of <4 and [Formula: see text]4, the statistical difference of 2-year PFS between these two groups was significant, too ([Formula: see text], [Formula: see text]),but there is no significant between-group difference in OS ([Formula: see text], [Formula: see text]). COX analysis revealed that D-5PS are the independent factors influencing PFS, while MTV is the independent influencing factor of OS.

CONCLUSION

The baseline total MTV obtained by PET/CT scanning, and D-5PS are crucial prognostic factors in evaluating the prognosis of PTCL-NOS.

Report of Eleven Patients of Subcutaneous Panniculitis-Like T-Cell Lymphoma: Clinicopathologic Features, 18F-FDG PET/CT Findings and Outcome

Objectives

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a fairly rare subtype of primary cutaneous lymphoma. This study aims to investigate the clinicopathologic features, ¹⁸F-FDG PET/CT findings, and outcome of patients with SPTCL.

Methods

A retrospective single-center study enrolled 11 patients with SPTCL between August 2010 and March 2020. A total of 26 ¹⁸F-FDG PET/CT scans were performed, and the initial and follow-up PET/CT imaging features, clinicopathologic and immunohistochemical characteristics, and outcome were analyzed.

Results

The male-to-female ratio was 1.2. The mean age at diagnosis was 24.2 years (age range: 13-48 years). Histopathological examinations revealed atypical T-lymphocyte rimming of individual subcutaneous adipocytes, mostly with CD2⁺, CD3⁺, CD4^-, CD5⁺, CD8⁺, CD56^-, T-cell intracellular antigen-1⁺, Granzyme B⁺, and high Ki-67 index. Multiple large skin ulcerations with a maximum diameter of 10 cm were observed in one of the 11 patients (9.1%, 1/11), and hemophagocytic syndrome was found in another one. At initial PET/CT scans, the lesions in all 11 patients showed increased uptake of ¹⁸F-FDG with a wide range of maximum standard uptake value (SUVmax) from 2.0 to 14.9. The morphology of the lesions presented as multiple nodules and/or disseminated plaques mainly involving the trunk and/or limbs. Five patients had extracutaneous non-lymph node lesions with SUVmax of 5.6 ± 2.8 on ¹⁸F-FDG PET/CT. No significant correlation between SUVmax and Ki-67 index was observed (r = 0.19, P > 0.05). Follow-up ¹⁸F-FDG PET/CT scans in six patients showed complete remission of the disease in two, partial remission in three, and progressive disease in one. During the follow-up period, there was no death except for the patient with multiple ulcerations who died 4 months after diagnosis of SPTCL.

Conclusions

SPTCL may be a group of heterogeneous diseases with varying degrees of ¹⁸F-FDG uptake. ¹⁸F-FDG PET/CT demonstrates its usefulness in detecting disease extent, providing diagnostic work-up, staging, and evaluating treatment response of SPTCL. Multiple large skin ulcerations may be a factor of poor prognosis for patients with SPTCL.

Extensive Extranodal Cutaneous Lymphomatous Involvement in a Case of Adult T-Cell Lymphoma - Advantage of 18F Fluorodeoxyglucose Positron-emission Tomography-Computed Tomography over Computed Tomography

Diffuse extranodal cutaneous lymphomatous involvement is a unique presentation in a case of adult T-cell lymphoma. We present the case of a 26-year-old female who presented with erythematous rashes with subsequent evaluation with 18F fluorodeoxyglucose positron-emission tomography-computed tomography showing enlarged inguinal and axillary lymph nodes, and biopsy findings from the inguinal lymph nodes were suggestive of adult T-cell lymphoma.

Prognosis and risk stratification of peripheral T-cell lymphomas

Peripheral T-cell lymphomas represent a rare heterogeneous group of non-Hodgkin lymphomas with generally worse outcomes with standard chemotherapy compared to B-cell lymphomas. Clinical risk prediction tools at baseline have been shown to be prognostic but generally do not impact clinical decision making. However, improving understanding of the prognostic implications of histology and its molecular underpinnings as well as strategies surrounding the use of CD30 as a predictive biomarker for brentuximab vedotin have led to better understanding of how to risk stratify patients. Baseline, interim, and end of treatment PET/CT as evaluated by the Lugano criteria as well as by baseline metabolic tumor volume have also been shown to be prognostic. The role of minimal residual disease tools such as cell free DNA and T-cell gene receptor sequencing remain active areas of investigation in hopes to develop predictive biomarkers in these rare diseases. This review focuses on strategies used to prognosticate in more common forms of peripheral T-cell lymphoma as well as in extranodal NK/T-cell lymphoma.

Baseline total metabolic tumor volume combined with international peripheral T-cell lymphoma project may improve prognostic stratification for patients with peripheral T-cell lymphoma (PTCL)

Purpose

The aim of this study was to explore the prognostic value of total metabolic tumor volume (TMTV) at baseline ¹⁸F-FDG PET/CT in patients diagnosed with peripheral T-cell lymphoma (PTCL).

Materials and methods

Eighty-four newly diagnosed PTCL patients who underwent baseline ¹⁸F-FDG PET/CT prior to treatment between March 2009 and January 2019 were enrolled in this retrospective study. The FDG-avid lesions in each patient were segmented using semiautomated software to calculate the maximum standardized uptake value (SUVmax), total metabolic tumor volume (TMTV), and total lesion glycolysis (TLG) values using the boundaries of voxels presenting with the 41% SUVmax threshold method. Progression-free survival (PFS) and overall survival (OS) were used as end points to evaluate patient prognosis. The log-rank test and Cox regression analyses were used to evaluate PFS and OS.

Results

ROC curve analysis indicated an ideal TMTV cut-off value of 228.8 cm³. During the 4–131 months (29.2 ± 28.5 months) follow-up period, high TMTV was significantly associated with worse PFS and OS. TMTV and the international peripheral T-cell lymphoma project score (IPTCLP) were independent predictors of PFS and OS with multivariate analysis. The combination of TMTV and the IPTCLP may provide significantly better risk substratification in PFS and OS of PTCL patients.

Conclusions

Both TMTV and IPTCLP are independent predictors of PTCL patient survival outcomes. Moreover, the combination of TMTV and IPTCLP improved patient risk stratification and may contribute to personalized therapeutic regimens.

Utility of bone marrow aspirate and biopsy in staging of patients with T-cell lymphoma in the PET-Era - tissue remains the issue

The role of 18F-fluoro-2-deoxy-D-glucose positron emission tomography combined with computerized tomography (PET-CT) in evaluation of bone marrow involvement (BMI) in patients with T-cell lymphoma (TCL) is poorly understood. We investigated whether PET-CT could replace bone marrow aspiration and biopsy (BMAB) in TCL. Sixty patients with newly diagnosed TCL who underwent both diagnostic PET-CT and BMAB were identified. BMI was tissue-confirmed in 15 (25%) cases, however only 8 of these 15 showed BMI on PET-CT (sensitivity of 53.3%, specificity of 100%). BMI by BMAB was associated with lower progression-free survival (PFS) (p = 0.038) and overall survival (OS) (p = 0.003) while PET-CT BMI was associated only with OS (p = 0.02). BMI detected by BMAB in the setting of a negative PET-CT had similar inferior prognosis as BMI identified on PET-CT. Thus, PET-CT in TCL misses BMI in almost half of the cases detected by BMAB and hence cannot substitute BMAB in evaluation of TCL.

Resolution of bone, cutaneous, and muscular involvement after haploidentical hematopoietic stem cell transplantation followed by post-transplant cyclophosphamide in adult T-cell leukemia/lymphoma

Haploidentical hematopoietic stem cell transplantation followed by post-transplant cyclophosphamide provides a well-tolerated and potentially curable treatment for chemorefractory acute-type adult T-cell leukemia/lymphoma.

Multiple Cutaneous Leiomyomas Showing Increased FDG Uptake

Cutaneous leiomyomas are rare, sporadic, or inherited benign tumors arising from smooth muscle cells of the skin associated with various disorders. We present a case of multiple cutaneous leiomyomas showing increased FDG uptake with SUVmax of 19.9. This case indicates cutaneous leiomyoma should be considered as a rare differential diagnosis in patients with hypermetabolic cutaneous lesions. Careful correlation with clinical history is needed to avoid misdiagnosis.

Baseline and interim functional imaging with PET effectively risk stratifies patients with peripheral T-cell lymphoma

The prognosis of peripheral T-cell lymphoma (PTCL) is heterogenous. Baseline or interim imaging characteristics may inform risk-adapted treatment paradigms. We identified 112 patients with PTCL who were consecutively treated with cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP)/CHOP-like regimens with the intent to consolidate with an autologous transplant. Baseline (n = 93) and interim (after 4 cycles, n = 99) positron emission tomography (PET) images were reevaluated, and we calculated baseline total metabolic tumor volume (TMTV). Interim PET (iPET) responses were graded visually by 5-point score (i5PS) and by percentage change of standardized uptake value. By univariate analysis, predictors of event-free survival (EFS) included Prognostic Index for Peripheral TCL (PIT) higher than 1 (hazard ratio [HR], 1.83; P = .021), International Prognostic Index (IPI) higher than 3 (HR, 2.01; P = .021), high TMTV (>125 cm³; HR, 3.92; P = .003), and positive iPET (HR, 3.57; P < .001). By multivariate analysis, high baseline TMTV predicted worse overall survival (OS; HR, 6.025; P = .022) and EFS (HR, 3.861; P = .005). Patients with i5PS of 1 to 3 had a longer median OS and EFS (104 months, 64 months) than those with i5PS of 4 to 5 (19 months, 11 months; P < .001). Four-year OS and EFS for patients with i5PS of 1 to 3 and PIT of 1 or less were 85% and 62%, respectively. However, 4-year OS and EFS for those with i5PS of 4 to 5 and PIT higher than 1 were both 0% (P < .001). In multivariate analysis, after controlling for IPI and PIT, i5PS was independently prognostic for EFS (HR, 3.400 95% confidence interval, 1.750-6.750; P < .001) and OS (HR, 10.243; 95% confidence interval, 4.052-25.891; P < .001). In conjunction with clinical parameters, iPET helps risk stratify patients with PTCL and could inform risk-adapted treatment strategies. Prospective studies are needed to confirm these findings.

Peripheral T-Cell Lymphoma Arising in Patients With Chronic Lymphocytic Leukemia

OBJECTIVES

To describe three further cases of anaplastic large cell lymphoma (ALCL) occurring in patients with preexisting chronic lymphocytic leukemia (CLL). We also reviewed the literature of previously published cases.

METHODS

We discuss the clinical features, histopathology, and outcomes for three patients with ALCL and CLL from Perth, Australia. The cases were also included in a literature review of existing cases and comparisons were made with our cohort.

RESULTS

The three patients included two men (aged 77 and 74 years) and one woman (aged 66 years). All had a history of untreated CLL with diagnosis established 4 to 16 years before. They had lymphadenopathy and/or cutaneous/soft tissue lesions that proved to be ALCL, ALK+ (one case) or ALCL, ALK- (two cases).

CONCLUSIONS

Further research is required in this area to establish prognostic and management recommendations. Increasing numbers of cases are being described. Positron emission tomography with computed tomography was not useful in our cohort for diagnosing progression.

ESMO Consensus Conference on malignant lymphoma: general perspectives and recommendations for the clinical management of the elderly patient with malignant lymphoma

The European Society for Medical Oncology (ESMO) consensus conference on mature B cell lymphomas and chronic lymphocytic leukaemia (CLL) was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (1) the elderly patient, (2) prognostic factors suitable for clinical use, and (3) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address clinically-relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the four questions assigned to their group. These recommendations were presented to the entire panel and a consensus was reached. This consensus, which was further developed in continuous post-meeting discussions, formed the basis of three manuscripts, each covering one of the three key areas identified. This manuscript presents the consensus recommendations regarding the clinical management of elderly patients diagnosed with malignant lymphoma. Four clinically-relevant topics identified by the panel were: 1) how to define patient fitness, 2) assessing quality of life, 3) diagnostic work-up and 4) clinical management of elderly patients with lymphoma. Each of these key topics is addressed in the context of five different lymphoma entities, namely: CLL, follicular lymphoma, mantle cell lymphoma, peripheral T-cell lymphoma and diffuse large B-cell lymphoma. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript.

Utility of PET-CT for Evaluation of Patients With Peripheral T-cell Lymphoma

BACKGROUND

Fluorine-18 fluorodeoxyglucose (FDG) avidity varies in peripheral T-cell lymphoma (PTCL). We evaluated FDG avidity of pretreatment positron emission tomography/computed tomography (P-PET/CT), to appraise the prognostic significance of interim PET/CT (I-PET/CT) and end of treatment PET/CT (E-PET/CT) in PTCL.

PATIENTS AND METHODS

We performed a retrospective cohort study of patients with newly diagnosed or relapsed PTCL who had received any chemotherapy regimen from 2008 to 2015 in a tertiary center. P-PET/CT, I-PET/CT, and E-PET/CT studies were centrally reviewed. The primary outcomes were the prognostic role of I-PET/CT and E-PET/CT on progression-free survival (PFS) and overall survival (OS). The secondary outcomes were P-PET/CT avidity, the prognostic role of other baseline characteristics, and the correlation between the PET/CT and bone marrow biopsy findings.

RESULTS

We included 40 patients in the present analysis. The median OS and PFS for the whole cohort was 39 and 16 months, respectively. Of the 40 patients, 36 had positive P-PET/CT findings. A total of 23 patients underwent I-PET/CT, with positive findings for 10. Of the 40 patients, 34 underwent E-PET/CT, 26 of which had positive findings. The sensitivity, specificity, and negative predictive value of P-PET/CT for bone marrow involvement was 40%, 83%, and 89%, respectively. The factors significantly associated with PFS and OS on univariate analysis included elevated lactate dehydrogenase, and low lymphocyte, hemoglobin, and albumin levels. On multivariate analysis, only lymphopenia remained prognostic for PFS and OS. The E-PET/CT and I-PET/CT results were not prognostic for PFS or OS.

CONCLUSION

Our study has shown that 90% of PTCL cases will be FDG avid. However, PET/CT was not predictive for PFS or OS at any point. The only predictive factor was the presence of lymphopenia.

FDG PET/CT in a Case of Human African Trypanosomiasis (Sleeping Sickness)

Human African trypanosomiasis imported to nonendemic countries is rare. It is very difficult to establish the correct diagnosis of human African trypanosomiasis in nonendemic areas. We present a case of human African trypanosomiasis with MRI and FDG PET/CT findings. Head MRI showed hyperintense areas in bilateral internal capsules. Abdominal and pelvic MRI showed hepatosplenomegaly and multiple enlarged lymph nodes. FDG PET/CT showed generalized hypermetabolic lymph nodes, diffuse FDG uptake of the spleen, and hepatosplenomegaly mimicking lymphoma. In addition, FDG PET/CT revealed decreased FDG uptake in the medial occipital cortex and cardiomegaly with pericardial effusion.

Peripheral T-Cell Lymphoma of the Submandibular Salivary Gland as an Unusual Manifestation of Richter's Syndrome: A Case Report and Literature Review

Richter's syndrome is the development of high-grade non-Hodgkin lymphoma (NHL) or Hodgkin lymphoma in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). In most patients with Richter's syndrome, the high-grade NHL is diffuse large B-cell lymphoma. Only a small minority of CLL/SLL patients develop T-cell malignancies. Herein, we describe a 40-year-old male patient presenting with peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) in the submandibular salivary gland, two years after the diagnosis of CLL/SLL. The PTCL-NOS consisted of small lymphocytes, which complicated diagnosis. Immunohistochemical, cytological, and molecular studies allowed the correct diagnosis of composite lymphoma (SLL/PTCL-NOS) of the submandibular salivary gland. The PTCL-NOS had a cytotoxic phenotype and aberrant expression of CD79a. There was no evidence to suggest that the PTCL-NOS of the submandibular salivary gland developed from an intimately associated submandibular lymph node or by PTCL-NOS dissemination. A review of the literature and presented case suppose that the PTCLs developed following CLL/SLL have the cytotoxic phenotype and can clinically mimic typical Richter's syndrome.

FDG PET for therapy monitoring in Hodgkin and non-Hodgkin lymphomas

PET using 18F-FDG for treatment monitoring in patients with lymphoma is one of the most well-developed clinical applications. PET/CT is nowadays used during treatment to assess chemosensitivity, with response-adapted therapy given according to 'interim' PET in clinical practice to adults and children with Hodgkin lymphoma. PET is also used to assess remission from disease and to predict prognosis in the pretransplant setting. Mature data have been reported for the common subtypes of aggressive B-cell lymphomas, with more recent data also supporting the use of PET for response assessment in T-cell lymphomas. The Deauville five-point scale incorporating the Deauville criteria (DC) is recommended for response assessment in international guidelines. FDG uptake is graded in relation to the reference regions of normal mediastinum and liver. The DC have been validated in most lymphoma subtypes. The DC permit the threshold for adequate or inadequate response to be adapted according to the clinical context or research question. It is important for PET readers to understand how the DC have been applied in response-adapted trials for correct interpretation and discussion with the multidisciplinary team. Quantitative methods to perform PET in standardized ways have also been developed which may further improve response assessment including a quantitative extension to the DC (qPET). This may have advantages in providing a continuous scale to refine the threshold for adequate/inadequate response in specific clinical situations or treatment optimization in trials. qPET is also less observer-dependent and limits the problem of optical misinterpretation due to the influence of background activity.

Pathogenesis and FDG-PET/CT findings of Epstein-Barr virus-related lymphoid neoplasms

Epstein-Barr virus (EBV) is one of the most common viruses, infecting more than 90% of the adult population worldwide. EBV genome is detected in some lymphoid neoplasms. Not only their histopathological subtypes, but also their backgrounds and their clinical courses are variable. A number of B-cell lymphoproliferative disorders associated with the immunocompromised state are related to EBV infection. The incidences of these disorders have been increasing along with generalization of organ transplantations and use of immunosuppressive treatments. Furthermore, some EBV-positive lymphoma can also occur in immunocompetent patients. While evaluating patients with generalized lymphadenopathy of unknown cause by positron emission tomography/computed tomography with 2-deoxy-2-[¹⁸F]fluoro-D-glucose (FDG-PET/CT), the possibility of lymphoid neoplasms should be considered in some patients, and a careful review of the background and previous history of the patients is necessary. In this review article, we describe the pathogenesis of EBV-related lymphoid neoplasms and then present FDG-PET/CT images of representative diseases. In addition, we also present a review of other EBV-related diseases, such as infectious mononucleosis and nasopharyngeal carcinoma.

Clinical usefulness of FDG-PET/CT for the evaluation of various types of adult T-cell leukemia

PURPOSE

The aim was to explore undefined useful indices for clinically grading adult T-cell leukemia (ATL) using [¹⁸F] 2-fluoro-2-deoxyglucose (FDG) - positron emission tomography/computed tomography (PET/CT).

METHODS

A total of 28 patients with ATL (indolent, 9; aggressive, 19) were enrolled; all patients with aggressive ATL underwent FDG-PET/CT before chemotherapy. Patients with indolent ATL underwent FDG-PET/CT at the time of suspected disease progression and/or transformation; some received lymph node biopsy. The quantitative parameters maximum standardized uptake values (SUVmax), and mean and peak SUV, metabolic tumor volume (MTV), and volume-based total lesion glycolysis were calculated with the margin threshold as 25%, and 50% of the SUVmax for all lesions.

RESULTS

All parameters except for MTV-25% showed significant differences (P ≤ 0.05) in differentiating the aggressive type from the indolent type of ATL. Areas under the curve for receiver-operating characteristic (ROC) analysis regarding the series of parameters investigated ranged from 0.75 to 0.92; this indicated relatively high accuracy in distinguishing the aggressive type from the indolent type. No malignant findings were detected in lymph node biopsies in indolent ATL patients with lymphadenopathy.

DISCUSSION

We performed evaluation of a line of parameters of FDG-PET, thereby demonstrating their significantly high accuracy for grading malignancy in ATL patients. In particular, low accumulation of FDG in indolent ATL patients with lymphadenopathy might predict that it is not a sign of disease transformation, but rather a reactive manifestation.

CONCLUSION

FDG-PET/CT findings could be useful for clinically grading ATL.

Angioimmunoblastic T-cell lymphoma: the many-faced lymphoma

Angioimmunoblastic T-cell lymphoma (AITL) is an uncommon subtype of mature peripheral T-cell lymphoma (PTCL). The history of AITL is much longer and deeper than the literature would suggest given the many names that have preceded it. Advanced-stage disease is common with uncharacteristic laboratory and autoimmune findings that often slow or mask the diagnosis. Significant strides in the immunohistochemical and molecular signature of AITL have brought increased ability to diagnose this uncommon type of PTCL. The 2016 World Health Organization classification of lymphoid neoplasms recently acknowledged the complexity of this diagnosis with the addition of other AITL-like subsets. AITL now resides under the umbrella of nodal T-cell lymphomas with follicular T helper phenotype. Induction strategies continue to focus on increasing complete remission rates that allow more transplant-eligible patients to proceed toward consolidative high-dose therapy and autologous stem cell rescue with improving long-term survival. There are several clinical trials in which recently approved drugs with known activity in AITL are paired with induction regimens with the hope of demonstrating long-term progression-free survival over cyclophosphamide, doxorubicin, vincristine, and prednisone. The treatment of relapsed or refractory AITL remains an unmet need. The spectrum of AITL from diagnosis to treatment is reviewed subsequently in a fashion that may one day lead to personalized treatment approaches in a many-faced disease.

Peripheral T-cell lymphoma, not otherwise specified

Peripheral T-cell lymphoma, not otherwise specified, is a broad category of biologically and clinically heterogeneous diseases that cannot be further classified into any other of the existing entities defined by the World Health Organization classification. Anthracycline-containing regimens, namely cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), nowadays represent the standard first-line treatment; for patients who achieve a satisfactory response, a consolidation by means of autologous stem cell transplantation may offer a greater chance of long-term survival. Several patients, however, display treatment refractoriness or relapse soon after obtaining a response, and just a few of them are suitable transplant candidates. This is why several new agents, with innovative mechanisms of action, have been investigated in this context: pralatrexate, romidepsin, belinostat, and brentuximab vedotin have been approved for relapsed and refractory peripheral T-cell lymphomas based on their activity, although they do not significantly affect survival rates. The incorporation of such new drugs within a CHOP backbone is under investigation to enhance response rates, allow a higher proportion of patients to be transplanted in remission, and prolong survival.

T-Cell Non-Hodgkin Lymphomas: Spectrum of Disease and the Role of Imaging in the Management of Common Subtypes

T-cell non-Hodgkin lymphomas (NHLs) are biologically diverse, uncommon malignancies characterized by a spectrum of imaging findings according to subtype. The purpose of this review is to describe the common subtypes of T-cell NHL, highlight important differences between cutaneous, various peripheral and precursor subtypes, and summarize imaging features and the role of imaging in the management of this diverse set of diseases.

Mycosis fungoides staged by 18F-flurodeoxyglucose positron emission tomography/computed tomography: Case report and review of literature

INTRODUCTION

Mycosis fungoides is a kind of malignant lymphoma arising from T cells, but primarily occurs in skin, and it is the most common type of cutaneous lymphoma. Mycosis fungoides (MF) is a rare non-Hodgkin lymphoma but the most common type of primary cutaneous T-cell lymphomas. Because of unknown etiology and mechanism, and lack of typical clinical and histophysiological manifestations, the final diagnosis of MF is currently dependent on pathology and immunohistochemistry. Subsequently, tumor staging is very important. Different approaches would be taken according to varying degrees of cutaneous and extracutaneous lesions. Computed tomography (CT) scan has been chosen to stage tumors customarily. However, CT could only provide morphological information and analyze lymphadenopathy by the size criteria. F-flurodeoxyglucose positron emission tomography/computed tomography (PET/CT) could provide morphological information and metabolic conditions simultaneously, which is helpful to locate and stage lesion.

CONCLUSION

F-flurodeoxyglucose PET/CT could identify cutaneous and extracutaneous lesions in patients with MF. It could provide the range of lesions and biopsy target.

Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography evaluation of subcutaneous panniculitis-like T cell lymphoma and treatment response

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a very rare variant of non-Hodgkin’s lymphoma. Currently, there is no standard imaging method for staging of SPTCL nor for assessment of treatment response. Here, we describe our use of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for staging and monitoring of treatment response in 3 cases of SPTCL. Primary staging by PET/CT showed that all 3 patients had multiple foci in the subcutaneous fat tissue, with SUVmax from 10.5 to 14.6. Involvement of intra-abdominal fat with high SUVmax was identified in 2 of the patients. Use of the triple drug regimen of gemcitabine, cisplatin and methylprednisolone (commonly known as “GEM-P”) as first-line therapy or second-line therapy facilitated complete metabolic response for all 3 cases. FDG PET/CT provides valuable information for staging and monitoring of treatment response and can reveal occult involvement of the intra-abdominal visceral fat. High FDG uptake on pre-treatment PET can identify patients with aggressive disease and help in selection of first-line therapy.

The utility of positron emission tomography with and without computed tomography in patients with nonmelanoma skin cancer

Combined positron emission tomography (PET) and computed tomography (CT) scans are widely used in the staging and monitoring of most malignancies. The differential for PET-positive cutaneous lesions includes primary skin cancers, infections, cutaneous metastases from distant malignancies, and benign neoplasms. In dermatology, PET/CT scans have been most widely studied in patients with melanoma and Merkel cell carcinoma. The role of PET/CT scans in the management of other cutaneous malignancies is less clear, but it has shown great promise in the management of patients with squamous cell carcinoma and cutaneous lymphoma. This review seeks to address the usefulness of PET/CT scans in nonmelanoma skin cancer and to provide guidance regarding the management of patients with incidental PET-positive nodules. Currently, there is limited experience with PET/CT scans for staging and monitoring of non-head and neck metastatic basal cell and squamous cell carcinomas, and results show limited sensitivity and specificity. We also address the evidence for management of an incidental PET-positive cutaneous nodule and recommend obtaining a biopsy specimen in patients with a known noncutaneous malignancy, a history of primary skin cancer, or a high risk of either cutaneous or noncutaneous malignancy.

Role of Surveillance Imaging in Patients With Peripheral T-Cell Lymphoma

INTRODUCTION

The role of surveillance imaging (SI) in patients with peripheral T-cell lymphoma (PTCL) in first complete remission (CR1) is unclear.

MATERIALS AND METHODS

Patients with PTCL were identified through prospectively maintained T-cell lymphoma databases from the National Cancer Centre Singapore/Singapore General Hospital and Weill-Cornell Medical College after institutional review board approval. Patients with leukemia or indolent, composite, and cutaneous lymphomas were excluded. The patients' medical records were retrospectively reviewed to determine the frequency and type of SI used. Of those with relapse, the method of relapse detection and data on symptoms, signs, and elevated lactate dehydrogenase LDH were extracted.

RESULTS

A total of 338 patients were included in the present study. In the first year after achieving CR1, patients had an average of 1.2 and a median of 1 SI performed (range, 0-4). In the second year after achieving CR1, they had an average of 0.78 and a median of 1 SI performed (range, 0-4). Of the 135 patients who achieved CR1, 61 (45%) developed a relapse. Relapses were detected before SI in 48 (84%), and 9 patients had relapses detected during routine SI. Of the 9 patients whose relapses were detected during planned SI, only 3 did not have any symptoms or signs suggestive of relapsed disease. Of these 3 patients, 2 had angioimmunoblastic T-cell lymphoma and 1 had natural killer/T-cell lymphoma.

CONCLUSION

Most PTCL relapses were detected before planned SI, and most patients had symptoms with relapse. Only 3 patients (5.2%) were completely asymptomatic at relapse, suggesting a limited utility of routine imaging for detecting PTCL relapses.

The role of fluorine-18 fluorodeoxyglucose positron emission tomography in patients with mycosis fungoides

Purpose:

The aim of the present study is to evaluate the possible role of fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸F-FDG PET-CT) in the management of mycosis fungoides (MF).

Materials and Methods:

Nineteen patients (mean age, 40.6 years; median age 41 years; 16 males and 3 females) with risk of secondary lymph node (LN) involvement (those with large cell transformation, tumors, erythroderma, or enlarged LNs on physical examination) were included in the study. All patients underwent PET-CT scan by injecting 0.06 mCi/kg of F18 FDG. The maximum standard uptake value (SUVmax) was recorded for each patient.

Results:

The ¹⁸F-FDG PET-CT was positive in 15 patients. PET-CT detected local cutaneous disease in 13 cases. The range of SUVmax is 2.8–14.1. Out of 19 patients, hypermetabolic adenopathy is found in 9 patients and visceral involvement in one.

Conclusions:

Although the study population is small our findings suggests that ¹⁸F-FDG PET-CT can detect cutaneous and extracutaneous lesions in MF and may guide biopsies especially in patients with risk of secondary LN involvement.

A case of granulomatous slack skin cutaneous T-cell lymphoma: PET/CT imaging findings

A 24-year-old female presented with granulomatous slack skin (GSS) cutaneous T-cell lymphoma. The patient underwent systemic chemotherapy. Owing to the development of several chemotherapy-related complications, therapy was discontinued. Subsequently, disease progression was noted clinically. Our patient’s disease progression was clearly demonstrated by 18F-fludeoxyglucose positron emission tomography (PET)/CT findings. PET/CT imaging findings of GSS have not yet previously been reported. In this report, we present PET/CT characteristics of a patient with GSS.

Utility of ¹⁸fluoro-deoxyglucose positron emission tomography for prognosis and response assessments in a phase 2 study of romidepsin in patients with relapsed or refractory peripheral T-cell lymphoma

BACKGROUND

For patients with peripheral T-cell lymphoma (PTCL), the value of (18)fluoro-deoxyglucose positron emission tomography (FDG-PET) scans for assessing prognosis and response to treatment remains unclear. The utility of FDG-PET, in addition to conventional radiology, was examined as a planned exploratory end point in the pivotal phase 2 trial of romidepsin for the treatment of relapsed/refractory PTCL.

PATIENTS AND METHODS

Patients received romidepsin at a dose of 14 mg/m(2) on days 1, 8, and 15 of 28-day cycles. The primary end point was the rate of confirmed/unconfirmed complete response (CR/CRu) as assessed by International Workshop Criteria (IWC) using conventional radiology. For the exploratory PET end point, patients with at least baseline FDG-PET scans were assessed by IWC + PET criteria.

RESULTS

Of 130 patients, 110 had baseline FDG-PET scans, and 105 were PET positive at baseline. The use of IWC + PET criteria increased the objective response rate to 30% compared with 26% by conventional radiology. Durations of response were well differentiated by both conventional radiology response criteria [CR/CRu versus partial response (PR), P = 0.0001] and PET status (negative versus positive, P < 0.0001). Patients who achieved CR/CRu had prolonged progression-free survival (PFS, median 25.9 months) compared with other response groups (P = 0.0007). Patients who achieved PR or stable disease (SD) had similar PFS (median 7.2 and 6.3 months, respectively, P = 0.6427). When grouping PR and SD patients by PET status, patients with PET-negative versus PET-positive disease had a median PFS of 18.2 versus 7.1 months (P = 0.0923).

CONCLUSIONS

Routine use of FDG-PET does not obviate conventional staging, but may aid in determining prognosis and refine response assessments for patients with PTCL, particularly for those who do not achieve CR/CRu by conventional staging. The optimal way to incorporate FDG-PET scans for patients with PTCL remains to be determined.

TRIAL REGISTRATION

NCT00426764.

Prognostic significance of interim PET/CT based on visual, SUV-based, and MTV-based assessment in the treatment of peripheral T-cell lymphoma

Backgrounds

The role of interim PET/CT in peripheral T-cell lymphoma (PTCL) is less identified compared to other subtype of lymphoma. This study prospectively investigated the prognostic accuracy of sequential interim PET/CT using visual and quantitative assessment to determine whether it provided prognostic information for the treatment of PTCL.

Methods

Sixty-three patients with newly diagnosed PTCL were enrolled, and 59 patients underwent interim PET/CT after three or four courses of induction treatment. The response of interim PET/CT was assessed by three parameters: the Deauville five-point scale (5-PS), ΔSUVmax, and ΔMTV2.5.

Results

Over a median follow up of 40.3 months, each assessment of interim PET/CT using the 5-PS, ΔSUVmax, and ΔMTV2.5 had predictive value for progression-free survival. To increase the predictive accuracy of interim PET/CT, we divided patients into three groups according to the sum of scores for three adverse responses based on the visual, SUV-based and MTV-based assessment: favorable, intermediate, and poor responder. The clinical outcome of patients in the favorable group was significantly superior to patients in the poor or intermediate group.

Conclusion

Visual, quantitative SUV-based, and MTV-based assessment in interim PET/CT are valuable for early treatment response assessment in patients with PTCL, and the combined approach using the three parameters was more efficient in discriminating between patients with different survival outcomes compared with single-parameter assessment.

Trial registration

NCT01470066.

Role of imaging in the staging and response assessment of lymphoma: consensus of the International Conference on Malignant Lymphomas Imaging Working Group

PURPOSE

Recent advances in imaging, use of prognostic indices, and molecular profiling techniques have the potential to improve disease characterization and outcomes in lymphoma. International trials are under way to test image-based response–adapted treatment guided by early interim positron emission tomography (PET)–computed tomography (CT). Progress in imaging is influencing trial design and affecting clinical practice. In particular, a five-point scale to grade response using PET-CT, which can be adapted to suit requirements for early- and late-response assessment with good interobserver agreement, is becoming widely used both in practice- and response-adapted trials. A workshop held at the 11th International Conference on Malignant Lymphomas (ICML) in 2011 concluded that revision to current staging and response criteria was timely.

METHODS

An imaging working group composed of representatives from major international cooperative groups was asked to review the literature, share knowledge about research in progress, and identify key areas for research pertaining to imaging and lymphoma.

RESULTS

A working paper was circulated for comment and presented at the Fourth International Workshop on PET in Lymphoma in Menton, France, and the 12th ICML in Lugano, Switzerland, to update the International Harmonisation Project guidance regarding PET. Recommendations were made to optimize the use of PET-CT in staging and response assessment of lymphoma, including qualitative and quantitative methods.

CONCLUSION

This article comprises the consensus reached to update guidance on the use of PET-CT for staging and response assessment for [18F]fluorodeoxyglucose-avid lymphomas in clinical practice and late-phase trials.

Utility of PET/CT in the diagnosis and staging of extranodal natural killer/T-cell lymphoma: a systematic review and meta-analysis

The role of 18F-fuorodexoyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) in the staging of Hodgkin lymphoma (HL) and aggressive B-cell non-Hodgkin lymphomas (NHL) has been demonstrated extensively. Nevertheless, the role of PET/CT in the diagnosis, staging, prognosis, and treatment evaluation of natural killer (NK)/T-cell lymphoma remains indeterminate. To systematically review and meta-analyze the publications on the value of 18F-FDG-PET/CT in the diagnosis and staging of NK/T-cell lymphoma. Pubmed, Embase, Cochrane Library, and some other database were searched for initial studies (last updated on May 8th, 2014).The eligibility criteria were studies assessing the usefulness of PET/CT in the staging of NK/T-cell lymphoma, patients were diagnosed as NK/T-cell lymphoma through pathology, or clinical and imaging follow-up. Sensitivities and specificities of 18F-FDG-PET/CT in individual studies were assessed. The summary receiver operating characteristic curve (sROC) and the area under the curve (AUC) were calculated. The "Meta-Disc 1.4" software was used for data analysis. Eight studies, with a total of 135 NK/T-cell lymphoma patients, were included in this meta-analysis. In terms of the 6 studies with patient based data, the pooled sensitivity and specificity of PET/CT in the diagnosis of NK/T-cell lymphoma were 0.95 (95% CI: 0.89-0.98) and 0.40 (95% CI: 0.09-0.78), respectively. For lesion-based analysis, with 1546 lesions included, the pooled sensitivity and specificity of PET/CT in the staging of NK/T-cell lymphoma were 0.98 (95% CI: 0.96-0.99) and 0.99 (95% CI: 0.99-1.00), respectively. For the patient based data, the AUC and Q index were 0.8537 and 0.7847, respectively. For lesion based data, the AUC and Q index were 0.9959 and 0.9755, respectively. The results of this current meta-analysis indicated that PET/CT could be used as a valuable diagnostic and staging tool for NK/T-cell lymphoma.

18F-FDG PET/CT findings in a patient with Sweet syndrome associated with myelodysplastic syndrome

A 73-year-old man was admitted to our hospital because of a 2-year history of repeated painful edematous erythemas on the skin and pancytopenia for the last 8 months. FDG PET/CT demonstrated multiple cutaneous foci with increased tracer accumulation throughout the body, multiple FDG-avid lymph nodes in the mediastinum, bilateral pulmonary hili and abdomen, and diffusively increased FDG uptake of bone marrow. A skin biopsy revealed infiltration by neutrophilic granulocytes consistent with Sweet syndrome. Myelodysplastic syndrome was established on bone marrow aspiration and biopsy.