Peripheral T‐Cell Lymphoma and Sutton's Law: The Need for Repeat Biopsies

Case Presentation:

Mr. B is a 68‐year‐old man with a history of melanoma and histoplasmosis infection who presented with an enlarged, painful left inguinal lymph node. This dramatically increased in size over 2 months, prompting emergency department evaluation. The patient had spent a significant amount of time in Brazil during the past 5 years and was bitten by the Borrachudo fly in recent months. Since that time, he noticed a 20 pound weight loss, increasing fatigue, early satiety, and low back pain. The patient also reported sexual activity with partners outside his marriage. On exam, Mr. B's left thigh was swollen to roughly 1.3 times the size of the right thigh, and there was an indurated, erythematous left inguinal lymph node measuring 4 × 4 cm. Initial lab work was significant for a white blood cell count of 10 × 10⁹/L of which 35.9% were eosinophils, and a lactate dehydrogenase (LDH) of 419 IU/L. Imaging revealed reticulonodular opacities at bilateral lung bases and extensive retroperitoneal, para‐aortic, and left inguinal lymphadenopathy. An initial lymph node biopsy revealed a reactive lymph node. A battery of serologic tests for bacterial, fungal and parasitic infections returned negative. A PET scan was performed to further explore the possibility of malignancy, which demonstrated multiple FDG‐avid lymph nodes throughout the body. A repeat biopsy of the inguinal lymph node revealed a peripheral T‐cell lymphoma.

Discussion:

T‐cell non‐Hodgkin's lymphoma is a relatively uncommon malignancy that represents about 10% of all lymphomas. Multiple subtypes of T‐cell lymphoma exist, all of which have unique characteristics, clinical behavior, and therapeutic responses. The most common subtype is peripheral T‐cell lymphoma, unspecified (PTCL‐u). PTCL‐u is most often seen in males in their sixties and is predominately a nodal lymphoma, typically accompanied by B symptoms and an elevated LDH Lymph node biopsies are known to contain varying amounts of necrosis and apoptosis, making it difficult to establish the diagnosis of lymphoma from That of a reactive process. This case underscores the importance of repeating the biopsy when a neoplastic process such as PTCL‐u is suspected. It also serves as a reminder that malignancy should be included in the differential for eosinophilia, with lymphoid disease being the most common malignant cause of eosinophilia.

Conclusions:

The diagnosis of PTCL‐u is difficult to make, and most patients present in an advanced stage of disease. This case illustrates the potential for being led astray by a negative biopsy result and the importance of pursuing additional biopsies. Furthermore, it demonstrates the association between eosinophilia and PTCL‐u.

Author Disclosure:

M. Baker. Harvard Medical School, Student; B. Vaughn, Beth Israel Deaconess Medical Center, employment; S. Schellhom, Beth Israel Deaconess Medical Center, employment