Peter A. S. Johnstone, MD

The role of radiation therapy (RT) in lung cancer is long established; some of the earliest Radiation Therapy Oncology Group reports dealt with non-small cell lung cancer (NSCLC).[1,2] More recently, the advent of stereotactic body RT (SBRT) techniques has provided significant local control rates after focused treatment of selected small metastases and inoperable early stage lesions.[3,4] Our center has been in the forefront of examining SBRT and its role in central [5] or bilateral [6] lesions, its effect on PET imaging [7] and pulmonary function testing,[8] and subsequent frequency of brachial plexopathy,[9] chest wall toxicity,[10] or pneumonitis.[11] Still, even this highly conformal technique comes with potentially significant dose to adjacent normal tissue. This is in the context of an emerging appreciation for the pulmonary consequences of elevated mean lung dose,[12] or V5 after pneumonectomy.[13] For each lung cancer patient requiring RT, an effective mechanism to deliver dose to the tumor while minimizing dose to uninvolved lung is called for. Enter protons.

Dr. Czito and colleagues provide an intriguing overview on adapting and using more technically advanced techniques to deliver radiation therapy for anal cancer patients. The paper starts with a brief history of the treatment of anal cancer, moving from abdominoperineal resection to combined-modality therapy with radiation and chemotherapy and discusses the trials showing that combined chemoradiotherapy is superior to radiation alone in terms of local control and colostomy-free survival.[1,2] Adding mitomycin to fluorouracil (5-FU) has been scrutinized for increasing toxicity but has been shown to decrease colostomy rates compared to cisplatin/5-FU or 5-FU alone.[3,4]

Xerostomia is a permanent and devastating sequela of head and neckirradiation, and its consequences are numerous. Pharmaceutical therapyattempts to preserve or salvage salivary gland function through systemicadministration of various protective compounds, most commonlyamifostine (Ethyol) or pilocarpine. When these agents are ineffective orthe side effects too bothersome, patients often resort to palliative care, forexample, with tap water, saline, bicarbonate solutions, mouthwashes, orsaliva substitutes. A promising surgical option is the Seikaly-Jha procedure,a method of preserving a single submandibular gland by surgicallytransferring it to the submental space before radiotherapy. Improved radiationtechniques, including intensity-modulated radiotherapy andtomotherapy, allow more selective delivery of radiation to defined targetsin the head and neck, preserving normal tissue and the salivary glands.Acupuncture may be another option for patients with xerostomia. All ofthese therapies need to be further studied to establish the most effectiveprotocol to present to patients before radiotherapy has begun.