Role of Radiation Oncology for Organ Structure and Function Preservation in Cancer
However, to achieve this, it is desirable to have a multimodality and planned approach right from the onset, with contribution and active participation in the decision making process from all concerned medical specialties - pathology, radiology, nuclear medicine and the three primary pillars of clinical oncology, namely – surgical, radiation and medical oncology.
A dedicated expert team is thus desirable to meticulously chart out the treatment policy for each individual patient based on the stage of the disease, general condition, socio-economic background, respecting individual's desires and wishes and supported by sound evidence from literature. The bottom line of the entire management outline should be not only to cure wherever possible, but provide a quality of life that gives value, meaning and pleasure to the added years in the patient's life following a successful treatment. This can be achieved only if treatment policies are tailored to provide cure along with preservation of structure and function of the diseased organ.
Radiation Oncology, one of the key modalities of cancer treatment has been there for more than 100 years. Although, the process and implication of surgery are very well understood by the public. Radiation therapy has been considered by most as one which "burns" the tissues. The irony is that it "does not burn tissues", but "destroys and kills the cancer cells," thereby paving the way for normal tissues to be restored both in its structure and function. Recent developments in technology, has helped to refine the radiation therapy process to precisely delivering radiation with not only utmost precision but also modify the intensity of dose based on the likely congregation of tumour cells in the tissues. Modern radiation therapy could be considered similar to the "Precision Guided Munition" whereby it is intended to precisely hit a specific target and minimize damage to adjacent structures. Thus, today with the help of various diagnostic modalities like CT, MRI and PET either alone or in combinations, one can delineate the cancer sites with utmost accuracy and then deliver radiation therapy through advanced techniques of Three dimensional Conformal Radiation Therapy (3D-CRT), Intensity Modulated Radiation Therapy (IMRT), Stereotactic Radiation Surgery (SRS), Stereotactic Radiation Therapy (SRT), Respiratory Gated Radiation Therapy (RGRT) and Adaptive Radiation Therapy (ART). All of these can be monitored during actual treatment delivery process under real time Image guidance (Image Guided Radiation Therapy-IGRT). All such capabilities are now available in the state-of-the art radiation oncology department ofDharamshilaHospital and Research Centre.
The above techniques constitute "teletherapy" and deliver radiation from outside the patient's body surface. However, one can also precisely deliver radiation by placing radiation sources safely within the tumour for short period, thereby further enhancing the doses to the tumour bearing tissues and minimizing its effect to the adjacent normal structures. This process of "Brachytherapy" can be either in form of intracavitary, interstitial, intralumenal and surface mould and can be applied to almost any site of the body. Together with the various teletherapy techniques as listed previously, modern radiation therapy techniques have helped in minimizing extent of surgical resection and when applied in a planned way with surgery and appropriate chemotherapeutic drugs, has helped in preservation of organ structure and function without any loss of tumour control.
Diiferent Treatment Modalities Advantage
Site-Treatment Modalities-Advantage
- Skin- Electron Beam+_Interstitial/Surface Mould- Cosmetic Preservation
- Head and Neck Tumours (Lip, Buccal Mucosa, Tongue, Floor of mouth, Larynx, Nasopharynx)- IGRT based 3D CRT/IMRT/ART+_Interstitial/Intralumenal/Brachytherapy+Limited Surgery+Chemotherapy- Cosmetic,Speech,Swallowing functions preserved
- Oesophagus- IGRT based 3D CRT/IMRT/ +_ /Intralumenal Brachytherapy+Chemotherapy- Swallowing functions preserved
- Breast- Breast Conservation Surgery+IGRT Based 3D CRT/IMRT+Interstitial brachythearpy- Cosmetic preservation
- Lung- IGRT based 3D CRT/IMRT/RGRT/SRS/SRT+_ Intralumenal /Brachytherapy+ Chemotherapy- Organ and function preservation
- Extremity soft tissue sarcoma, bone tumors-Surgery+External radiotherapy+ Interstitial Brachytherapy- Limb Salvage, Function preserved
- Cervix,Vagina- IGRT based 3D CRT/IMRT+_Intracavitary/Interstitial/ Brachytherapy+ Chemotherapy-Organ preservation
- Urinary Bladder- IGRT based 3D CRT/IMRT+_Intracavitary/Interstitial/ Brachytherapy+ Chemotherapy- Organ and function preservation
- Prostate- IGRT based 3D CRT/IMRT+_Interstitial/ Brachytherapy+ Hormonal therapy- Organ and function preservation
- Penis- External radiotherapy+Interstital Brachytherapy/Surface Mould- Organ and function preservation
- Anal Canal- IGRT based 3D CRT/IMRT +_Interstitial//Brachytherapy+ Chemotherapy- Colostomy Free, Organ and function preservation
To be able to help patients with cure and preservation of organ function, it is of utmost importance to have early staged tumours which are still localized to their site of origin. Early diagnosis is thus of utmost importance and patients need to be encouraged to seek medical attention at an appropriate facility having all these facilities. Various tumour sites which have been successfully managed with organ preservation using these state-of-art radiation therapy techniques are listed. However, all these can be practiced with a team approach of all the clinical oncology specialties – surgical, radiation and medical with unrivalled contributions from all.