The laser theatrics of Star Wars have nothing on the latest treatment in clinical trials for patients with certain forms of lung cancer.
As the clinical research coordinator for the lung cancer program at Penn Presbyterian Medical Center in Philadelphia, Melissa Culligan, BSN, RN, is involved in clinical trials of photodynamic therapy (PDT) for patients with cancer of the pleura (lung lining) or mesothelioma, an asbestos-related lung cancer.
The current treatment for these cancers is chemotherapy, which typically offers a median survival of 6-9 months. PDT, which employs a photosensitizing agent activated by laser light, changes the picture entirely.
"We offer a light-based cancer treatment for patients with stage III-B non-small cell lung cancer and have demonstrated an increased median survival of 27 months - that's huge," Culligan told ADVANCE.
PDT combines an IV-injected nontoxic photosensitizing agent with a laser light to kill cancer cells. Culligan and her colleagues use a specific wavelength of laser light to activate a photosensitizer called Photofrin, or porfimer sodium, which has been FDA-approved to treat or relieve the symptoms of esophageal cancer.
"Photofrin is a photosensitizer, but here, at the University of Pennsylvania, we are using it in off-label applications - in clinical trials to treat different types of cancer," Culligan said. "Some research teams are examining its effectiveness for head and neck cancers, superficial skin cancers and prostate cancer. Our research team is focused on patients who would otherwise die from their lung cancer within the year."
PDT For Lung Cancer
For patients with these deadly cancers, the research team injects Photofrin intravenously and takes the patient to the OR the next day. Photofrin is absorbed instantly by all cells of the body, but it concentrates in cancer cells. In the OR, the surgeon performs a debulking procedure.
"This can range from a radical pleurectomy to an extrapleural pneumonectomy, which involves removal of the lung, pleura, diaphragm and a portion of the pericardium, and then reconstructing those areas," Culligan said.
The surgical debulking removes macroscopic cancer cells, but does not take care of removing cancer that is not visible.
"This is not a surgical procedure where you can tell the patient and their family 'the cancer has been removed completely,'" Culligan emphasized. "Based on the way the cancer has spread throughout the chest cavity, we know microscopic disease is being left behind.
That is where PDT comes into play. "
To treat the remaining cancer cells within the chest cavity, the surgeon shines a laser light into the patient's thoracic cavity before closing the chest. The Photofrin in the cancer cells is activated by the laser light and, in the presence of oxygen, triggers a cell-death process. After the surgeon closes the chest cavity, this process continues to kill cancer cells for an additional 48 hours.
Culligan previously traveled to Taiwan as part of a research team involved in the international pleural PDT program led by Joseph Friedberg, MD, a thoracic surgeon from the University of Pennsylvania.
"My role in Taiwan was to teach the nurses how to care for these patients postoperatively, as well as work with their research team in the coordination of this complex clinical trial," she said. "In addition to the general thoracic surgical postop care, we need to consider the effects of the photodynamic therapy, which is essentially a third-degree burn within the chest."
Culligan shared the tremendous nursing challenges seen during the immediate postoperative period after PDT.
"Patients may experience large fluid shifts related to the burn, and can sometimes alternate between being too dry and developing volume overload," Culligan said. "These patients seem to be at additional risk for deep venous thrombosis, post-pneumonectomy pulmonary edema and bleeding. Intensive monitoring as well as early mobilization is critical for these patients to avoid postoperative and post-PDT complications."
Culligan emphasized the need for extensive and continuous patient and family education around the topic of PDT.
"Going into this experimental procedure, patients and their family members are often so anxious about the cancer, the possibility of death and the procedure itself they don't retain much of the postop information we provide pre-operatively," she explained. "After surgery, we need to continue giving them information in small pieces along the continuum of care. The nursing care of these patients is invaluable, from the initial evaluation to the continued follow-up care once the patients have been discharged to home."
"Not all patients with these cancers are medically appropriate candidates for an aggressive surgical procedure, unfortunately," Culligan said. "We're working on ways to deliver the light externally, potentially avoiding a surgical procedure, but it's not at the clinical trial stage yet."
Sandy Keefe is a frequent contributor to ADVANCE.