(18)F-FDG PET in Patients with Primary Systemic Anaplastic Large Cell Lymphoma: Differential Features According to Expression of Anaplastic Lymphoma Kinase. Nucl Med Mol Imaging. 2013;47:249-256. [PMID: 24900120 DOI: 10.1007/s13139-013-0224-6]

18 F-FDG PET/CT in Synovial Anaplastic Large Cell Lymphoma

ABSTRACT

Anaplastic large cell lymphoma is an uncommon and aggressive form of peripheral T-cell lymphoma. Synovial anaplastic large cell lymphoma is very rare. We present PET/CT findings in a patient with synovial anaplastic large cell lymphoma. Intense FDG accumulation was found in irregular synovial thickening of the right knee. Biopsy of the synovium was performed and revealed anaplastic large cell lymphoma. This case demonstrates that anaplastic large cell lymphoma should be included as one of the differential diagnoses of FDG-avid synovial lesions.

Evolution of 18F-FDG Uptake as a Pitfall of Image Diagnosis for Systemic Anaplastic Large Cell Lymphoma

In most patients, systemic anaplastic large cell lymphoma (sALCL) is an ¹⁸F-FDG-avid tumor. Both ALK-positive and ALK-negative tumors can be evaluated by PET scans as both tumor types uptake ¹⁸F-FDG in PET. The PET scan is also valuable in predicting prognosis during and after the treatment course. The evolution of ¹⁸F-FDG uptake in patients with sALCL has not been reported. For tumors lacking ¹⁸F-FDG uptake, there is a diagnostic pitfall of underestimating the cancer stage and misjudgment of metastases. In the present case, the PET scan results were negative at diagnosis but disseminated ¹⁸F-FDG avid lesions were found at relapse. Biopsy of bone marrow and lymph nodes revealed the pathological features were identical to the original tumor at the time of diagnosis. In the wake of such evolutional change, physicians dealing with sALCL should be cautious in interpretation of PET/CT scans.

Rapidly progressing primary pulmonary lymphoma masquerading as lung infectious disease: A case report and review of the literature

BACKGROUND

Primary anaplastic large cell lymphoma of the lung represents a diagnostic challenge due to diverse manifestations and non-specific radiological findings, particularly in cases that lack extra-pulmonary manifestations and lung biopsy.

CASE SUMMARY

A 40-year-old woman presented with a 6-d history of fever, dry coughing, and dyspnea. Her white blood cell count was 20100/mm3 with 90% neutrophils. PaO2 was 60 mmHg and SaO2 was 90% when breathing ambient air. Chest computed tomography (CT) identified a solid nodule, 15 mm in diameter, with a poorly defined boundary in the upper right lung, and several smaller solid nodules throughout both lungs. Pulmonary artery CT and subsequent bedside X-ray showed diffuse patchy shadows throughout both lungs. Repeated cultures of blood samples and alveolar lavage failed to identify any pathogen. Due to the mismatch between clinical and imaging features, we conducted a bone marrow biopsy, and the results showed proliferation along all three lineages but no atypical or malignant cells. The patient received empirical antibacterial, antiviral, and antifungal treatments, as well as corticosteroids. The patient's condition deteriorated rapidly despite treatment. The patient died 6 d after hospitalization due to respiratory failure. Post-mortem lung biopsy failed to show inflammation but identified widespread infiltration of alveolar septum by anaplastic lymphoma kinase (ALK)-positive anaplastic cells.

CONCLUSION

ALK-positive anaplastic large cell lymphoma could present as a primary pulmonary disease without extra-pulmonary manifestations.

FDG PET/CT in Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma

Anaplastic large cell lymphoma (ALCL) is a rare non-Hodgkin's lymphoma, with rearrangements of the anaplastic lymphoma kinase gene in 60%-85% of systemic cases. We report an 11-year-old boy with ALCL in whom serial FDG PET/CT revealed partial response and complete metabolic response at interim and end of treatment, respectively. However, the patient relapsed within 2 weeks, confirmed by cytology. Because of the inherent aggressive nature of ALCL, possibility of an early relapse should always be kept in mind.

Clinicopathological characteristics of primary central nervous system lymphoma with low 18F-fludeoxyglucose uptake on brain positron emission tomography

Primary central nervous system lymphoma (PCNSL) typically shows a strong uptake of F-fludeoxyglucose (FDG) imaged by positron emission tomography (PET). Uncommonly, PCNSL demonstrates a low uptake on FDG PET. We investigated the clinicopathological characteristics of the unusual cases of PCNSL with low FDG uptake.We retrospectively enrolled 104 consecutive patients with newly diagnosed PCNSL who underwent baseline brain FDG PET. The degree of FDG uptake of PCNSL was visually scored by 4 grades (0, ≤contralateral white matter; 1, >contralateral white matter and <contralateral gray matter; 2, = contralateral gray matter; 3, >contralateral gray matter). Grades 0-2 were considered as PCNSL with low uptake. We investigated association of low uptake of PCNSL with the following clinicopathological factors: age, sex, steroid treatment, lactate dehydrogenase level, cerebrospinal fluid protein level, condition of PET scanning, immunohistochemical markers (cluster of differentiation 10 [CD10], B-cell lymphoma 6 [BCL-6], B-cell lymphoma 2 [BCL-2], multiple myeloma oncogene 1 [MUM1], Epstein-Barr virus [EBV] protein, and Ki67), location of lesions, tumor size, multiplicity of lesions, involvement of deep brain structures, and cystic or necrotic appearance of lesions.Of the 104 patients with PCNSL, 14 patients (13.5%) showed PCNSL with low FDG uptake on PET. Among various clinicopathological factors, MUM1 negativity was the only factor associated with low FDG uptake PCNSL by univariate (P = .002) and multivariate analysis (P = .007).This study suggests that the different clinicopathological characteristics between patients with high uptake and low uptake of PCNSL on FDG PET is closely associated with lack of MUM1, a protein known to be a crucial regulator of B-cell development and tumorigenesis.

18F-FDG PET/CT imaging findings in anaplastic large cell lymphoma, a rare subtype of lymphoma

OBJECTIVE

To investigate the 18F-FDG PET/CT imaging manifestations for anaplastic large cell lymphoma (ALCL), a rare subtype of T/NK cell lymphoma.

METHODS

Fifty patients with ALCL, including 32 anaplastic lymphoma kinase (ALK)-positive patients and 18 ALK-negative patients, were enrolled. The positive detection, maximal standardized uptake value (SUVmax), and distribution of nodal and extranodal involvement were recorded and analysed. Fifty patients with diffuse large B cell lymphoma (DLBCL) were collected as a control group.

RESULTS

ALCL lesions were demonstrated to be 18F-FDG-avid tumours with a mean SUVmax of 19.4 ± 12.6. Most (76%) ALCL patients presented with stage III-IV disease, and nodal and extranodal involvement occurred in 74.0 and 72.0% of the patients, respectively. ALCL and DLBCL showed many similarities in tumour stage, 18F-FDG uptake and tumour involvement (P > 0.05), although the preferred extranodal organs of involvement (bone and the gastrointestinal tract, respectively) were different (P < 0.05). Compared to ALK-negative lesions, a higher uptake of 18F-FDG was found in the ALK-positive lesions (SUVmax: 22.1 ± 14.3 vs. 15.1 ± 6.6, t = 2.354, P = 0.023). ALK-positive ALCL was more likely to involve the lymph nodes than ALK-negative ALCL (84.3% vs. 55.5%, χ2 = 4.973, P = 0.043), while ALK-negative ALCL was more prone to involve the extranodal organs compared to ALK-positive ALCL (88.9% vs. 62.5%, χ2 = 3.979, P = 0.046).

CONCLUSION

The present study demonstrated that ALCL is a systemic 18F-FDG-avid lymphoma with many imaging manifestations similar to DLBCL on PET/CT. The present study also showed that ALK expression actually influenced tumour 18F-FDG uptake and lesion distribution. These findings may be useful to improve the understanding of the biological characteristics of ALCL.

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.