Abstract Introduction/Objective ALK-positive anaplastic large cell lymphoma (ALCL) is a mature T-cell lymphoma that accounts for approximately 3% of non-Hodgkin lymphoma cases in the adult population. Lymph node involvement is most commonly seen, followed by extra-nodal involvement of the skin, soft tissue, and bone. Central nervous system involvement is rare at the time of diagnosis. This case study features a patient with systemic ALK-positive ALCL involving multiple nodal and extra-nodal sites, most notably the spinal cord. Methods/Case Report A 22-year-old female presented to the hospital with worsening back pain accompanied by neurological symptoms. MRI scans of her spine revealed extensive patchy abnormal marrow signal with enhancement of the thoracolumbar vertebrae (T1-L2) and adjacent extension into the spinal canal (T3-T7, T10-L1, L3-S1) and paraspinal soft tissues. A laminectomy of the T5-T7 and T11-T12 levels was performed for surgical decompression, and epidural and paraspinal resection specimens were submitted. These specimens, along with an excisional axillary lymph node biopsy, demonstrated ALK-positive ALCL after comprehensive immunohistochemical studies. In-situ hybridization for EBV was negative. CHOP therapy was initiated, but treatment was complicated by Candidemia and disseminated intravascular coagulation. The patient rapidly declined and passed away less than a month after hospital admission. At autopsy, enlargement of lymph nodes, the left ovary (17.8 g), and spleen (383.6 g) were noted on gross examination. A solid, white-tan lesion (2.1 x 0.9 x 0.8 cm) was found in the left ovary. Necrosis and infiltrates of large, pleomorphic lymphoid cells with irregular nuclear contours and prominent nucleoli were seen on microscopic examination of the spinal cord and leptomeninges, vertebral bone marrow, mediastinal lymph nodes, spleen, and left ovary. Consistent with previously submitted surgical specimens, the viable neoplastic cells stained strongly positive for ALK-1, CD4, and CD30. Results (if a Case Study enter NA) NA Conclusion This case study highlights an atypical presentation of ALCL with a fatal outcome. Given the availability of effective treatment options, prompt diagnosis is crucial to improving survival outcomes. Additional research is necessary to elucidate the clinical and pathological features of ALCL. The differential for back pain is broad, but including this entity for patients with similarly insidious clinical presentations can prevent a delay in diagnosis that allows for rapid progression of disease.