Review of her plain radiographs demonstrated no bony abnormalities, fractures, nor visible deformity (Figures 1A, 1B).
At presentation, our differential diagnosis included recurrence of the malignancy, secondary malignancy, infection, and inflammatory disease. After a lengthy discussion with the patient and consultation with our institution’s musculoskeletal oncologist, the decision was made to perform a right-ankle mass biopsy and marginal excision with wound irrigation and débridement and tarsal tunnel release.
The patient was placed in the supine position with standard prepping and draping. The medial eschar was excised in an elliptical fashion, and a curvilinear, longitudinal approach was performed within the compartment to access the mass along the posteromedial aspect of the ankle. Although no evidence of infection was observed, the tissue was thickened with areas of necrosis down to the flexor retinaculum. Once the flexor retinaculum was opened, a fibrous, plaque-like mass was observed, and it was encased with flexor tendons and neurovascular structures of the tarsal tunnel. After mass excision, a complete tarsal tunnel release was performed until the neurovascular bundle was free. Irrigation and débridement of the ulcer were performed along with complicated wound closure, and the patient was placed in a well-padded postoperative splint.
Pathology was finalized as a recurrent, EBV-positive, and nasal-type ENKTL. The patient underwent bone marrow biopsy, which yielded negative results. CT of the chest, abdomen, and pelvis were negative for the disease. FDG PET-CT, which included the extremities, was performed and demonstrated increased uptake in the right ankle, consistent with the malignancy (Figure 4).
DISCUSSION
ENKTL is an uncommon form of lymphoma and is exceedingly rare in Caucasian females.1-3 Although the patient’s primary occurrence was in the nasal cavity, recurrence in the foot and ankle must still be described.7,8 To our knowledge, this article is one of the first published cases of a patient who developed a rare-recurrence ENKTL about the foot and ankle. Occurrence in extremities is extremely rare that the staging protocol does not include FDG PET-CT of these areas. The patient’s “negative” scans led many providers to neglect the symptoms in her right ankle until the lesion had ulcerated through the skin. If one would have relied on imaging reports and outside records alone, the diagnosis would have been delayed longer or missed all together. This case illustrates the importance of a thorough medical history and personal review of imaging studies, and how a systematic approach can produce the correct diagnosis for any unknown lesion. Furthermore, this case may prompt oncologists to consider obtaining whole-body FDG PET-CT when evaluating for recurrence in patients.