Lung sparing surgery + photodynamic therapy = winning combo for mesothelioma treatmentWhile it's still in the experimental stage, a novel form of multi-mode treatment for malignant pleural mesothelioma (MPM) is showing great promise - at least, if a new study from the University of Pennsylvania has anything to say about it.
Combining lung sparing surgery with a cutting-edge, light-activated form of chemotherapy, this one-two clinical punch has resulted in "unusually long survival rates" among patients with late-stage mesothelioma. The full results of a small trial of the method appeared in the latest issue of the journal Annals of Thoracic Surgery.
Leaving lungs intact
Several of the most common surgeries for MPM involve the removal of one entire lung. Both pleurectomy/decortication (a relatively conservative procedure) and extrapleural pneumonectomy, or EPP (a radical operation), eliminate the affected lung, and sometimes much more.
For the new investigation, researchers from the university's Perelman School of Medicine wanted to see if lungs can be spared during thoracic surgery for mesothelioma. To that end, the team instead performed radical pleurectomies for 38 patients with Stage III or IV MPM.
In this procedure, the lungs are left as they are, while surgeons remove the entire double-layered sac that surrounds the lung tissue. (It is in this thin lining, called the pleura, that MPM originates.)
However, this is not all the researchers did to treat mesothelioma. The team also performed photodynamic therapy (PDT) during the procedure.
Light-activated chemo kills tumors from within
As one of the most technologically advanced forms of treatment for mesothelioma, PDT works in a unique way. In this mode of treatment, researchers inject a specially formulated chemical into the tissue, usually hours or days before the active stage of therapy.
Then, after MPM tumors have absorbed the chemo agent, surgeons expose the affected tissue to bright light of a particular wavelength. This causes the drug to react with oxygen in the body, almost immediately destroying tumor cells.
This mode of treatment is much more targeted than other chemo regimens. According to the American Cancer Society, it can only be applied to skin or tissues that can be exposed during surgery - which, fortunately for MPM patients, include the lungs and pleura.
And even more fortunately, this combo regimen appears to work very well. In the study, researchers reported that the median survival time of all participants was 32 months, which is significantly better than the 16 months associated with EPP.
"While I don't consider anything short of a cure as a victory against mesothelioma, I am encouraged by our results," lead authors Joseph Friedberg said. "Based on our new findings, we are redoubling our clinical and translational research efforts to find a way to further improve and refine this multimodality treatment approach for mesothelioma."
The results also far surpassed those of a previous investigation that looked at the benefits of mixing radical pleurectomy with intraoperative radiation.
Scientists try to predict survival after surgery for advanced mesothelioma, http://ejcts.oxfordjournals.org/content/early/2012/12/12/ejcts.ezs648.abstract, 12/21/12
Study reviews two chemotherapy regimens for operable mesothelioma, http://ar.iiarjournals.org/content/32/12/5393.full.pdf+html, 12/11/12
Study: Multimodal therapy for mesothelioma should be tailored to each patient, http://icvts.oxfordjournals.org/content/early/2012/11/21/icvts.ivs465.full, 11/30/12
Response to chemotherapy may identify candidates for mesothelioma surgery, http://annonc.oxfordjournals.org/content/early/2012/11/06/annonc.mds537.short, 11/29/12
Tomotherapy may be safe for mesothelioma patients after surgery, http://journals.lww.com/jto/Abstract/2012/12000/Tomotherapy_after_Pleurectomy_Decortication_or.18.aspx, 11/29/12
Chemotherapy delivery through thigh may help mesothelioma patients, http://radiology.rsna.org/content/early/2012/11/09/radiol.12111858.abstract, 11/21/12
Researchers compare outcomes of mesothelioma surgeries, http://art.torvergata.it/handle/2108/72282, 11/20/12
Mesothelioma treatment receives orphan drug designation, http://www.morphotek.com/news-events/News-Archive/2012-News/FDA-Grants-Orphan-Drug-Status-to-Morphotek-s-Amatu.aspx, 11/14/12