In 2007, a New Zealand woman named Tricia Spence was diagnosed with breast cancer that had spread to her bones and lymph nodes. Her oncologists recommended a full mastectomy followed by radiotherapy and chemotherapy. But Tricia decided instead to take a more holistic path. She opted first for an anti-cancer nutritional regimen along with Qigong and meditation. She then learned about a hospital in China that offered minimally invasive, low-toxic cancer treatments, including a potent strategy called sonodynamic-photodynamic therapy, or S-PDT. Recent lab studies in China indicate that S-PDT holds great promise for the treatment of metastatic breast cancer.
Tricia began her S-PDT regimen by ingesting a chorophyll-based photosensitizing agent that concentrates preferentially in cancer cells. The photodynamic portion of the treatment involved laying on a bed illuminated with high-intensity infrared lights. The light waves activate the photosensitizer inside cancer cells, generating highly reactive forms of oxygen that destroy those cells. Research suggests this treatment can also help the immune system better recognize and eliminate metastases—the most lethal part of any cancer diagnosis.
Tricia’s PDT sessions were followed by ultrasound treatment that entailed laying in a tub of warm water as the ultrasound was focused over areas of cancer. Ultrasound also activates the chorophyll-based agent but has the advantages of allowing for deeper penetration of organs and tissues, thus killing cancer cells that may not be reached by laser light. (Intriguingly, many of the photosensitizing agents used in PDT are also activated by the sonic waves used in ultrasound.)
Other key components of Tricia’s treatment regimen were the following: (1) immunotherapy, specifically a dendritic cell and cytokine-induced killer immunotherapy, or DC-CIK; (2) ozone therapy, which increases the amount of oxygen to the body through the introduction of ozone; (3) Chinese herbal medicines; (4) Zometa, for bone thinning and bone pain associated with the metastases; and (5) low-dose chemotherapy, which activates the immune system against cancer. However, the core treatment strategy used at the Chinese hospital was the S-PDT.
(Note: In a previous Discoveries post, we shared the exciting results of a Dutch study of PDT combined with immunotherapy. Much evidence shows that PDT enhances the efficacy of strategies that bolster the anti-cancer immune defenses. Specifically, PDT not only targets the primary tumor but also enables the immune system to better eradicate deadly metastases.)
Tricia’s cancer responded quite well to the treatment. By November 2011, scans showed that the five-centimeter tumor in her right breast was gone, along with all the lymph node metastases and half the bone metastases. The only major side effect was fatigue, which the doctors attributed to the cancer cells breaking down and releasing toxins. Despite a recurrence in 2011, Tricia has continued to do well, enjoying an excellent quality of life and traveling back to China periodically for follow-up evaluations and treatments as needed. Her tumor markers have continued to decline, further evidence that the treatments have been working.
New Insights into PDT’s Impact on Breast Cancer
Researchers at Wayne State University School of Medicine in Detroit, Michigan (USA), recently studied some of the mechanisms by which different PDT strategies may be able to help overcome aggressive breast cancer. The main focus of this study was inflammatory breast cancer (IBC), a rare and highly metastatic form of breast cancer. IBC is characterized by a reddish-orange color of the breast tissue as well as blockage of the lymphatic system, which in turn causes swelling of the breast.
In general, IBC appears to have a very poor prognosis. The conventional treatment trio of surgery, radiation, and chemotherapy is less effective against IBC than most other types of breast cancer, and there are no effective targeted therapies for the disease. For this reason, the use of PDT is being explored as a possible new treatment option for women diagnosed with IBC.
For their laboratory study, the Detroit research team used a three-dimensional cell-culture model of breast cancer and tested two different photosensitizers, one a porphyrin derivative and the other a chlorin e6 compound. These compounds were studied either alone or in combination, with the latter involving their sequential activation by light.
The researchers found that the “photokilling” of aggressive breast cancer cells by PDT was optimal when the chlorin e6 was followed by the other photosensitizer. Using this combined approach, more than 90 percent of the breast cancer cells were destroyed. Increasing the light dose led to greater destruction of the breast cancer cells.
Overall, this study’s findings suggest that combinations of photosenstiizers, when used sequentially, could provide a therapeutic advantage against IBC. It is known that the two different agents have different effects on cancer cells. Whereas the porphyrin agent mainly targets the mitochondria (tiny energy factories inside the cell), the chlorin e6 shows a strong affinity for sac-like structures in the cancer cell that store protein-degrading enzymes. By targeting these structures in a sequential manner, PDT could eradicate highly aggressive tumors and metastases.
The study also showed that PDT holds considerable promise for even the most lethal forms of breast cancer. These so-called triple-negative breast cancers, which can be either IBC or non-IBC, are characterized by the loss of hormone and growth factor receptors. The researchers concluded that “PDT may be useful for treating triple-negative breast cancer chest wall metastases that would be easily accessible to light.”
In the past, PDT has been successful against the progression of chest wall metastasis, with significantly improved survival for breast cancer patients. The Detroit researchers propose that PDT as a potential option for eradicating the skin metastases that are among the hallmarks of IBC and other aggressive breast cancers, as reported online ahead-of-print in the 26 October 2015 issue of Breast Cancer Research and Treatment.
Aggarwal N, Santiago AM, Kessel D, Sloane BF.Photodynamic therapy as an effective therapeutic approach in MAME models of inflammatory breast cancer. Breast Cancer Res Treat. 2015 Oct 26. [Epub ahead of print]
Wang P, Li C, Wang X, Xiong W, Feng X, Liu Q, Leung AW, Xu C. Anti-metastatic and pro-apoptotic effects elicited by combination photodynamic therapy with sonodynamic therapy on breast cancer both in vitro and in vivo. Ultrason Sonochem. 2015 Mar;23:116-27.
Internet links for the story on Tricia Spence: