AITL is an aggressive subtype of peripheral T-cell lymphoma derived from T-follicular helper cells, accounting for roughly 2 percent of all non-Hodgkin lymphomas and 15 to 20 percent of peripheral T-cell lymphomas. It is characterized by prominent inflammatory and immune dysregulation, with typical clinical features including lymphadenopathy, B symptoms such as fever, night sweats and weight loss, and hypergammaglobulinemia. Additional features may include anemia, hemolysis and hepatosplenomegaly. Skin involvement occurs in approximately half of all AITL patients, but it usually takes the form of rash or pruritus, which is frequently misdiagnosed as a drug eruption or viral exanthem. AITL presenting primarily with multiple subcutaneous nodules, without any of these more typical cutaneous signs, is exceedingly rare.

The patient in this case first noticed nodules on his back one month before seeking medical attention in September 2025, after which the lesions spread to his trunk and upper limbs. He denied any pruritus or pain and reported no fever, night sweats or weight loss. He also had no history of tuberculosis, hepatitis, leprosy or other infectious diseases. On physical examination, clinicians observed multiple subcutaneous nodules measuring approximately 0.5 to 2 centimeters in diameter on the back, chest, abdomen and upper limbs. The nodules were moderately firm, non-tender and covered by dark red infiltrative plaques, without ulceration or purulent discharge.

Laboratory investigations revealed mild anemia, with a hemoglobin level of 112 g/L, along with mildly elevated inflammatory markers, including C-reactive protein at 18 mg/L and an erythrocyte sedimentation rate of 35 mm/h. Serum immunoglobulin analysis showed decreased IgA at 0.86 g/L and elevated total serum IgE at 198.25 IU/mL, while IgM and IgG levels remained within normal ranges. Autoimmune and infectious screening, including antinuclear antibody, extractable nuclear antigen antibody, antineutrophil cytoplasmic antibody, Epstein-Barr virus, HIV and treponema pallidum tests, were all negative. Computed tomography imaging then revealed multiple mildly enlarged mediastinal lymph nodes, with the largest measuring approximately 20 mm in short-axis diameter, as well as widespread lymphadenopathy in the cervical, supraclavicular, axillary, mediastinal, retroperitoneal, pelvic and inguinal regions.

The diagnostic breakthrough came from histopathological examination of an excisional biopsy specimen taken from the left inguinal lymph node and from the subcutaneous nodules themselves. Pathologists found that the normal architecture of the lymph node was completely interrupted, with destruction of the germinal centers and an absent mantle zone. CD21 immunohistochemistry demonstrated disruption of the follicular dendritic cell meshwork within the lymph node, showing a branching and wind-swept pattern. There was marked proliferation of high endothelial venules with a branching pattern and endothelial cell swelling, along with basement membrane-like material deposition in the vessel walls and stroma. In the paracortical region and around blood vessels, a relatively diffuse infiltration of neoplastic T cells with clear cytoplasm was observed.

Immunohistochemical analysis proved positive for CD3, CD4, CD5, CD10, CXCL13 and Ki67 at 40 percent, while staining for CD20, CK-pan and CD8 was negative. In situ hybridization for EBV-encoded RNA was positive in scattered cells. Critically, the subcutaneous nodules yielded immunophenotypic findings similar to those seen in the lymph node, including consistent expression of PD-1 and CXCL13 in both sites. Based on these histopathological and immunohistochemical examinations, a diagnosis of AITL was finally established, and the patient was transferred to the hematology department of another hospital for further treatment. Pathological review at the referring institution confirmed the diagnosis, classified as Ann Arbor stage III.

To place this case in context, the authors conducted a literature review of rare cutaneous presentations of AITL. Previous reports have described dermatomyositis-like skin lesions in an elderly man who developed widespread erythematous papules over the extensor surfaces of the finger joints, shoulders and back, as well as a distinctive psoriasiform dermatitis with intermittent trailing scale. A case from Japan documented AITL manifesting as erythema multiforme with targetoid lesions and central bullae, while another described agminated miliary facial papules initially misdiagnosed as reactive B-cell hyperplasia. Other reported cutaneous manifestations include angioedema, prurigo-like lesions and linear IgA bullous dermatosis. The present case is noteworthy in that the initial presentation consisted of multiple subcutaneous nodules without pruritus or rash, posing a significant diagnostic challenge.

Several differential diagnoses were considered and systematically excluded. Leprosy was initially suspected because of the erythema nodosum-like skin lesions, but the typical clinical features such as nerve impairment or hair loss were absent. Connective tissue diseases, including systemic lupus erythematosus and dermatomyositis, were ruled out due to negative autoantibody results and the absence of systemic manifestations such as myalgia or arthritis. Subcutaneous nodules can also be associated with internal malignancies, including gastric or lung cancer, but the patient had no known history of primary malignancy and imaging did not reveal a primary tumor. Notably, cutaneous metastases typically present as firm, isolated nodules, whereas the diffuse infiltrative pattern observed in this case is rarely seen in metastatic disease.

The authors emphasize that cutaneous lesions in AITL may represent either reactive immune-mediated manifestations or true neoplastic infiltration secondary to systemic lymphoma involvement. Reactive lesions are thought to result from immune dysregulation and cytokine release, whereas neoplastic lesions usually demonstrate infiltration by TFH phenotype lymphoma cells and are often associated with systemic disease progression. In this case, the widespread lymphadenopathy, histopathological confirmation of AITL in the lymph node, and the similar immunophenotypic findings in both lymph node and subcutaneous lesions favored secondary cutaneous involvement by AITL rather than a purely reactive process. The authors acknowledge that the absence of molecular clonality analysis in the skin lesion remains a limitation of the study.

Treatment consisted of six cycles of chidamide plus CHOP chemotherapy, a regimen combining the oral histone deacetylase inhibitor chidamide with the conventional CHOP backbone. The patient achieved complete response, with complete resolution of the subcutaneous nodules and superficial lymphadenopathy, and remained free of recurrence at follow-up. Standard first-line treatment for AITL currently relies on CHOP or CHOEP-based regimens, achieving complete remission rates of approximately 40 to 60 percent, but relapse is frequent and the overall prognosis remains poor, with a five-year survival rate of approximately 30 to 40 percent. Several emerging therapeutic strategies, including anti-CD30 antibody conjugates, hypomethylating agents such as decitabine and PD-1 inhibitors, are being explored, though the authors caution that these agents should be used carefully in clinical practice as they may be associated with immune-related adverse events. The case broadens the recognized cutaneous spectrum of AITL and underscores the importance of considering lymphoma in the differential diagnosis of unexplained subcutaneous nodules.

Subject of Research: A rare presentation of angioimmunoblastic T-cell lymphoma with multiple subcutaneous nodules as the primary cutaneous manifestation

Article Title: Multiple subcutaneous nodules as the primary presentation of angioimmunoblastic T-cell lymphoma: a case report and literature review

Article References: Li, Y., Cai, Y., & Xu, X. (2026). Multiple subcutaneous nodules as the primary presentation of angioimmunoblastic T-cell lymphoma: a case report and literature review. Pathology & Oncology Research, 32, Article 1612446. https://doi.org/10.3389/pore.2026.1612446

Image Credits: AI Generated

DOI: 10.3389/pore.2026.1612446

Keywords: angioimmunoblastic T-cell lymphoma, subcutaneous nodules, cutaneous manifestations, peripheral T-cell lymphoma, case report, immunohistochemistry, CHOP chemotherapy, chidamide, lymphadenopathy, differential diagnosis, T-follicular helper cells, Epstein-Barr virus

A significant study conducted by Lin et al. investigates the effects of combining radiotherapy with systemic therapy on early mortality rates among patients diagnosed with AITL. This groundbreaking research provides vital insights that may revolutionize treatment protocols for this along with various other aggressive lymphomas in the hematological landscape. The team’s findings suggest a stark reduction in early mortality rates, illustrating the immense benefit of comprehensive therapeutic approaches tailored for AITL patients.

Historically, T-cell lymphomas have been notoriously resistant to treatment. Standard therapies often embrace a combination of chemotherapy and targeted agents. Nevertheless, the adverse prognostic factors associated with AITL, particularly in advanced stages, add layers of complexity to patient management. The role of radiotherapy as a supplementary treatment modality has often been underestimated but is now receiving the attention it deserves based on new evidence provided by Lin and colleagues.

The study highlights that early-stage AITL patients who received both systemic therapy and radiotherapy demonstrated a marked improvement in survival rates compared to those receiving systemic treatment alone. This finding begs the question of whether existing treatment guidelines should be revised to incorporate radiotherapy more routinely in managing AITL. The synergy between the two therapeutic approaches not only tackles the tumor effectively but also has implications for patient quality of life.

Radiotherapy operates through targeted action, maximizing the damage to cancer cells while minimizing collateral impact on surrounding healthy tissues. This precision is crucial in AITL management, where the disease frequently presents as a disseminated condition. The incorporation of advanced technologies in radiation delivery, such as intensity-modulated radiation therapy, further enhances the effectiveness and safety of this treatment modality.

As AITL progresses, there is a tendency for the tumor microenvironment to foster immune evasion, making systemic therapies less effective. The integration of radiotherapy may counteract these immunosuppressive mechanisms, reinvigorating the immune response and allowing systemic agents to work more effectively. This dual-action approach could potentially signify a major breakthrough in the fight against AITL.

The authors of the research article propose a multidisciplinary strategy in managing AITL, which involves hematologists, radiation oncologists, and pathologists working collaboratively. Such interdisciplinary involvement is essential not just for administrating treatment but also for appropriately selecting patients who might benefit most from radiotherapy. Clinical decision-making requires a nuanced understanding of each patient’s unique characteristics, including genetic markers and specific disease presentations.

While the study produced robust statistical data to support the use of radiotherapy, it is essential to proceed with caution. As any new treatment paradigm is considered, it is critical to conduct further research and validation studies to confirm these exciting findings. Randomized controlled trials with larger patient cohorts will be necessary to solidify the role of radiotherapy in AITL treatment protocols.

Another intriguing facet of the research concerns the potential economic implications of combining treatments. The early intervention with radiotherapy not only improves survival rates but may also reduce overall healthcare costs by preventing disease recurrence and the subsequent need for more aggressive treatments. Analyzing the cost-effectiveness of this treatment combination is essential for maximizing healthcare resources.

Furthermore, the study opens avenues for future research into identifying biomarkers predictive of treatment response. If specific genetic or molecular markers can be linked to sensitivity to radiotherapy, clinicians might better tailor treatments to the individual patient. Such personalized approaches could lead to better outcomes and an overall improvement in the standard of care for AITL.

In summary, the study authored by Lin et al. marks a pivotal moment in the treatment landscape for angioimmunoblastic T-cell lymphoma. By illuminating the benefits of combining radiotherapy with systemic therapy, we might be on the cusp of a new standard of care for this challenging malignancy. As the medical community digs deeper into this subject matter, continuous discussions and advancements in treatment strategies will be critical in improving patient outcomes.

Overall, this emerging research offers a glimpse into an integrated approach that could potentially reshape how clinicians address not only AITL but various forms of aggressive lymphomas. The findings challenge existing paradigms and advocate for incorporating radiotherapy into the treatment arsenal, leading to enhanced survival and improved quality of life for patients grappling with this formidable disease.

While it is easy to feel optimistic about these findings, researchers emphasize the importance of collaborative efforts and further validation to ensure that the results can be generalized across diverse patient populations. Continued research in this area is crucial, as the complexities of AITL demand innovative and robust treatment responses.

In summary, the future of angioimmunoblastic T-cell lymphoma treatment appears promising, anchored in the significant findings stemming from rigorous research efforts. With combined therapies becoming increasingly recognized for their synergistic effects, the patient-centered approach to managing this aggressive malignancy heralds an exciting new chapter in hematology.

Subject of Research: Angioimmunoblastic T-cell lymphoma treatment.

Article Title: Radiotherapy in addition to systemic therapy reduces the early mortality of angioimmunoblastic T-cell lymphoma.

Article References: Lin, Y., Lin, Q., Xu, Q. et al. Radiotherapy in addition to systemic therapy reduces the early mortality of angioimmunoblastic T-cell lymphoma. Ann Hematol 105, 57 (2026). https://doi.org/10.1007/s00277-026-06796-6

Image Credits: AI Generated

DOI: https://doi.org/10.1007/s00277-026-06796-6

Keywords: Angioimmunoblastic T-cell lymphoma, radiotherapy, systemic therapy, early mortality, treatment strategies, hematology.