Bicarbonate for Tumor Related Pain

The purpose of this study is to:

* Determine how well people tolerated sodium bicarbonate taken by mouth in higher doses than those usually given for heartburn.
* Determine if sodium bicarbonate can reduce cancer-related pain. Right now, the investigators do not know for sure if these higher doses will be well tolerated or if they will reduce the pain associated with cancer. The investigators are doing this study to see if sodium bicarbonate is well tolerated and if it can reduce the requirements for pain medications.

The study is a single institution, non-randomized, single arm pilot study to evaluate the efficacy of adjuvant therapy with sodium bicarbonate for tumor related pain. Patients will receive sodium bicarbonate (0.15 g/kg/day for 1 weeks and if tolerated 0.3 g/kg/day for one week and if this dose is tolerated 0.6 g/kg/day) for 4 weeks. The sodium bicarbonate will be provided to the patient as a powder and consumed after it is mixed with about 250 cc (about 1 cup) of water. In consultation with the PI, the patients will be permitted to mix the sodium bicarbonate with a commercially available drink instead of water provided the liquid has an acid/base balance (pH) of 7.4 or greater. Patients with a good tolerance to study therapy and with at least a 30% improvement in pain intensity (by VAS) compared to baseline after 3 weeks of therapy and who wish to continue study therapy will be allowed to continue sodium bicarbonate therapy under the direction of their treating physician. Patients without at least a 30% improvement in pain intensity at 3 weeks will discontinue study therapy.

Eligibility Criteria:
Inclusion Criteria:

* Patients must have metastatic or unresectable solid malignancy or hematologic malignancy (multiple myeloma or lymphoma) and must have moderate to severe tumor related pain (VAS\>4) on a stable opioid regimen (at least 3 days of an opiate regimen).
* No planned palliative surgery, palliative radiotherapy for at least 2 weeks. However prior radiotherapy, and surgery is allowed and not limited to the number of procedures and courses. Concomitant chemotherapy is allowed. In addition, when it is anticipated that chemotherapy may result in rapid pain relief (less than 2 weeks), patients will only be enrolled after completing their first cycle of chemotherapy and provided their pain level is greater than 4 on the VAS.
* No evidence of neurologic or psychiatric compromise which in the opinion of the investigator will interfere with completion of study assessments
* Life expectancy greater than 3 months
* Age greater than 18 years and able to understand and sign the informed consent document
* Patients must have an Eastern cooperative oncology group (ECOG) performance status less than 4.

Exclusion Criteria:

* Patients with neuropathy and/or neuropathic pain as the only pain syndrome are not eligible. Patients with chronic non malignant pain are not eligible.
* Patients with renal insufficiency (creatinine \> 2.5 mg/dL) are excluded
* Patients with history of congestive heart failure or pulmonary artery hypertension will be excluded
* Any patient who in the opinion of the investigator is dehydrated at the time of initial evaluation will be excluded.
* Patients with uncontrolled hypertension (systolic pressure \>140, diastolic pressure \>90) despite maximal antihypertensive therapy.
* Patients unable to ingest of oral sodium bicarbonate (such as patients with dysphagia or severe nausea)
* Patients with ECOG performance status 4
* Patients with acute leukemia, myelodysplastic syndrome, and chronic myeloid leukemia are not eligible.
* Pregnant or lactating patients are not eligible.
* Patients with estimated survival less than 3 months
* Patients with known allergy to sodium bicarbonate or patients with preexisting renal or acid base disorders for which sodium bicarbonate is contraindicated (such as metabolic alkalosis, severe congestive heart failure, hypernatremia, and hypocalcemia \[see above\]).
* Patients with severe ongoing infections which places the patients at increased risks from therapy in the opinion of the investigator.
* Patients who are receiving and or will receive, during their participation in study, an oral chemotherapeutic agent whose bioavailability could be altered by the ingestion of sodium bicarbonate.