Introduction

Tumor lysis syndrome (TLS) is a potentially fatal oncologic emergency caused by rapid destruction of malignant cells, leading to the release of intracellular potassium, phosphorus, and nucleic acids into the systemic circulation [1]. The resulting metabolic derangements include hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia, acute kidney injury, cardiac arrhythmias, seizures, and death if not promptly recognized and treated [2]. TLS is diagnosed using the Cairo-Bishop criteria: laboratory TLS requires two or more of the following abnormalities occurring within three days before or seven days after cytoreductive treatment: uric acid ≥8 mg/dL, potassium ≥6 mEq/L, phosphorus ≥4.5 mg/dL, or calcium ≤7 mg/dL (or a 25% change from baseline for each parameter); clinical TLS additionally requires evidence of renal impairment, cardiac arrhythmia, or seizures [1,2].

TLS is most commonly observed after initiation of cytotoxic therapy in patients with highly proliferative hematologic malignancies, particularly acute leukemias and high-grade lymphomas [2,3]. In contrast, spontaneous TLS, occurring in the absence of anticancer therapy, is uncommon and has been reported only rarely in solid tumors [4-6]. Recognized risk factors for spontaneous TLS in solid tumors include high tumor burden, rapid cell proliferation, high chemosensitivity, elevated baseline lactate dehydrogenase and uric acid levels, preexisting renal insufficiency, and dehydration [4]. Among gynecologic malignancies, ovarian carcinoma represents an especially unusual setting for spontaneous TLS, with only a handful of cases reported in the literature to date [7], and current oncologic guidelines do not specifically address this presentation [8].

We report a case of spontaneous TLS as the initial manifestation of previously undiagnosed advanced ovarian carcinoma presenting with severe metabolic abnormalities and acute kidney injury. Early recognition and treatment resulted in complete renal recovery, allowing subsequent multimodal oncologic therapy that culminated in a complete pathologic response and complete metabolic remission.