Due to constraints of COVID19, we were unable to recruit on-site for this study.

The purpose of this study is to observe whether PARP inhibitors have an effect on serum creatinine level, and whether this reflects a change in creatinine secretion or a true change in kidney function.

PARPi medications interact with transporters along the renal tubules involved in the secretion of creatinine and an increase in serum creatinine is often observed in patients treated with these agents; however, it is not known whether PARP inhibitors are associated with an actual change in the glomerular filtration rate, or if the observed elevations of serum creatinine are a result of a drug effect on creatinine secretion unrelated to changes in kidney function. The investigators therefore propose a prospective observational study to examine the incidence of elevation in serum creatinine from baseline levels in patients initiated on PARP inhibitors and compare the estimated glomerular filtration rate based on creatinine to that from alternative tests.

The primary purposes of this study are to:

• Assess the incidence of increase in serum creatinine in patients with a solid-organ cancer on treatment with a PARP inhibitor.
• To compare the estimated glomerular filtration rate based on serum creatinine with that of alternative biomarkers to assess whether changes in serum creatinine reflect changes in kidney function or creatinine secretion.
• To examine the persistence or resolution of creatinine increase and/or GFR decrease noted after discontinuation of PARPi

Inclusion Criteria:

• Adult patients age 18 years or older
• Diagnosed with any solid organ cancer
• Planned to receive a PARP inhibitor (olaparib, niraparib, rucaparib, veliparib, or talazoparib)
• Able to consent to study related procedures
• If unable to give informed consent, must have healthcare proxy or legally authorized representative
• Fluent in conversational English (Informed Consent form currently in English language)

Exclusion Criteria:

• Patients who will not receive ongoing cancer care at Penn Medicine
• Major psychiatric illness or cognitive impairment that in the judgment of the study investigators or study staff would preclude study participation
• Any patients who are unable to comply with the study procedures as determined by the study investigators or study staff
• Patients on dialysis

All patients will be recruited from the medical and gynecologic oncology practices at the Abramson Cancer Center / University of Pennsylvania. Patients that are 18+ years or older with a solid organ cancer who are being initiated on PARP inhibitor therapy.