History
A 64 year old female came to our clinic for treatment of metastatic ovarian carcinoma. She had been previously treated with standard chemotherapy regimens until the cancer developed resistance. She had known peritoneal carcinomatosis with incomplete bowel obstruction, and was told by her gynecologic oncologist that there was no further treatment available. The patient could only tolerate a liquid diet due to generalized cramping abdominal pain after meals. There were no significant prior health problems except for hypothyroidism. Medications included L-thyroxine, hydromorphone, and bromazepam.
Findings
She presented with cachexia and tympanic distended abdomen with palpable bowel loops. Body weight was 43.2kg. Vital signs were normal.
Treatment
The patient consented to DCA treatment and was started at 23 mg/kg/day (500mg p.o. b.i.d.), on a cyclic treatment of 1 week on, and 1 week off. She was supplemented with vitamin B1 100mg p.o. t.i.d., and R alpha lipoic acid 300mg p.o. t.i.d. She was also started on pantoprazole 40mg p.o. q.d. to prevent GI upset. The pre-treatment CA-125 was 826.
After 1 week of DCA treatment, there was marked reduction in abdominal swelling, reduction in abdominal cramps, and improvement in bowel movements. During DCA treatment, the CA-125 consistently declined. See table:
| Pre-DCA | 1st DCA cycle | 2nd DCA cycle | 3rd DCA cycle | |
|---|---|---|---|---|
| CA-125 | 826 | 732 | 646 | 618 |
After the 3rd DCA cycle the patient was able to progress from a liquid-only diet to a soft diet. She experienced fatigue and sedation which were directly attributed to the DCA and to progressive anemia (Hb dropped from 103 to 90 g/L over the 3 DCA cycles). As a result, the bromazepam was gradually reduced from 6mg qHS to 1.5mg qHS.
She was started on Eprex 40000IU s.c. weekly after the third DCA cycle to treat the anemia. The only other significant changes in blood tests over the course of DCA treatment were a drop in albumin from 25.4 to 19.8 (normal range 33-46) and a normalization of LDH from 253 to 191 (normal range 76-200).
The fatigue was coincident with the weeks on DCA, and improved during the weeks off DCA. After 3 DCA cycles she also experienced unstable gait and had a fall. As a result the DCA had to be stopped. In the weeks after stopping DCA, there was rapid clinical disease progression. Blood tests were not continued for patient comfort.
Comments
This is another one of our earlier cases of DCA. The patient was quite weak and advanced stage when DCA treatment was started. Based on our experience we felt that a moderate DCA dose with a 1 week on and 1 week off regimen could be effective and gentle enough for the patient to tolerate. If DCA was likely to work we might start to see some benefit and would prevent side effects by taking a week off.
This case illustrates a partial response of ovarian cancer to DCA treatment. Response was confirmed by a steady drop in the tumour marker CA-125 while the patient received DCA. The drop in CA-125 was consistent with the clinical improvement. DCA in the absence of other treatment resulted in significant quality of life improvement by relieving a bowel obstruction similar to our experience in other patients (including the Mesothelioma case report). Some of the blood tests worsened indicating incomplete control of the cancer.
This case also illustrates the DCA side effects of sedation and fatigue. Unfortunately in this case, the side effects were felt to be significant enough to stop DCA treatment and not restart it. In our practice, patients who experience fatigue from DCA generally do feel better after the DCA treatment is stopped. While fatigue may be tolerable in a relatively healthy patient, in advanced stage patients, it can be a major limiting factor in continuing DCA treatment. So far we have not been able to effectively control this side effect in the patients who experience it. We have noticed this side effect in about 20% of our patients. Fatigue is also more likely to be experienced quite soon after starting DCA treatment unlike neuropathy which usually occurs after a more prolonged exposure and can be controlled to some degree by supplements like alpha liopoic acid. As in other therapies, optimal DCA treatment has to be an individual balance between clinical benefit and side effect tolerability.