Evaluation Of Dental Management Of Oral Cancer Patients Undergoing Radiotherapy

“No man, even under torture can say what a tumour is” -Rudolf Virchow

Cancer is a major health problem. Carcinoma of oral cavity is an extensive term that comprises diverse malignant diagnoses. Oral cancer is a disease of antiquity, sushruta samhita, a Sanskrit treatise of surgery, written in the Indian context gives a description of oral cancer. It becomes very aggressive in nature and can spread locally as well as distantly. It inculpates in neighboring structures which leads to defacement. It influences the entire body function which in turn causes physical and pysological discomfort eventually distress the quality of life. Carcinoma of oral cavity persists as one of the greatest demanding malignancies of the head and neck region due to composite anatomy and cumbersome recuperation. Oral cavity includes the lips, the labial and buccal mucosa, the anterior 2/3rds of the tongue, the retromolar pad, the floor of mouth, the gingival and the hard palate. The oropharynx includes the palatine and lingual tonsils, the posterior 1/3rd base of tongue), the soft palate and posterior pharyngeal wall.

Inherent and generative are the two important factors responsible for most diseases. Carcinoma involving oral tissues is rising in Indian subcontinent mainly due to poor oral health practices, use of tobacco in form of smoking and chewing and many other factors. The second most common cause of morbidity and mortality is “Cancer”. Six million people die due to cancer every year.

Carcinoma of oral cavity comprises 6th place in the world. Oral cancer incorporates diverse group of abnormal growth whether benign or malignant. These abnormal growths diversify in its origin tissue, histopathology and anatomic location where they grow.

The utmost purpose for the treatment of carcinoma of mouth is not only to eliminate carcinoma but to maintain or re-impose function. Treatment should be emphasized to diminish the sequelae of treatment and eventually prevent any successive new primary cancers. To attain these goals, currently obtainable treatment modalities comprise surgery, radiotherapy, chemotherapy, combined modality treatments. Treatment should embrace primary and secondary prevention approach which includes lifestyle modification and chemoprevention. Three factors are designated that affects the choice of existing treatment as following: Tumor factors, patient factors and physician factors.

Tumor factors comprise of principal area, dimensions (T stage), position (front and rear), adjacency to bone (upper and lower jaw), lymph nodes present in neck, earlier treatment and histology. Patient factors incorporates age, medical history, forbearance to treatment, profession of patient, integration and compliance by patient, habits like smoking and drinking and other considerations. Physician factors, in order to lead triumphant effect of treatment, multi-disciplinary action is needed in diverse specialties like surgery, radiotherapy, chemotherapy, rehabilitation services, dental and prosthetic support, and psycho-social support.

Surgical approaches

Dimensions of principal abnormal growth, its deepness of invasion, position of tumor that is front versus rear location and closeness of tumor to upper and lower jaw are all components that affect the surgical approach for primary tumor.

The cornerstone of medical care for carcinoma of mouth is generally surgery. There are three circumstances in which EBRT with or without chemotherapy is habitually engaged.

1. Enhancing the action of medical treatment to principal resection to intensify cases of restricted localized region of body with adverse morbid characteristics.
2. Principal medical care for cases incompatible to resection.
3. Re-instate medical care in the sustained or repeated disease situation.

Indications of RT in carcinoma of oral cavity

1. Principal background
• Initial disease when patient is incompatible of surgery.
• Early disease when predicted esthetic outcome of surgery is distressing for eg lip carcinoma involving commissure area.
• Unresectable disease generally merged with chemptherapy.
• Advanced cases incompatible of resection due to low presentation status or presence of one or more concurrent disease.
2. Adjuvant background
• Incompatible adverse morbid characteristics.
• Concurrent with chemotherapy for positive resection borders and extracapsular nodal extension.
3. Rescuer background
• Enhancing the action of medical care after rescue resection.
• Principal medical care procedure, generally simultaneous with chemotherapy if further surgery is not attainable.

Low risk (all) (Huang et al)

• T1-T2
• Clear resection margin (>5mm)
• No LVI
• No microscopic muscle invasion Intermediate risk (any) (Langendjk et al)
• T3-T4
• Close resection margin
• LVI
• PNI
• Positive lymph node(s) without ECE

High risk (any) (Bernier et al)

• Positive resection margin
• ECE

Treatment

• Surgery alone
• Expected Outcome
• 5-year LRC:>90% (only restrospective data available)

Treatment

• PORT Expected Outcome
• 5-year LRC:~78%
• Treatment effect size:(PORT vs surgery alone) Mishra et al
• 30% difference in DFS
• 10% difference in OS but NS

Treatment

• pocrt expected outcome
• 5-year LRC:~80%
• treatment effect size:(POCRT vs PORT) Bernier et al
• 28% difference in OS
• 42% difference in LRC

RT, exclusively or amalgamated with surgery or chemotherapy has shown remarkable enhancement in treatment of numerous malignancies. RT exhibits various uninvited responses during or after the end of therapy. Ionizing radiation exhibits destruction in normal tissues present in radiation field which incorporates on skin, maxilla, mandible and salivary glands.

Mucositis, dryness of mouth, loss of taste dysfunction, reduced mouth opening, caries induced by radiation, soft tissue necrosis, osteoradionecrosis are the few examples of RT complications, eventually distressing the patients’s life. The aforementioned oral impediments persuading due to RT involves composite, vital and pathobiological process that affects the patient’s qualitative life.

Premature dental guidance and procedures (if required) are the ultimate method to reduce these oral difficulties. Preferably dental screening and required dental procedures should be carried before the start of RT.

There are two categories of oral complications of RT depending on its time of manifestation.

• Acute complication which appear through the time of RT.
• Chronic complications which manifests after the end of RT.

For prevention and treatment of complications arising due to RT, it is necessary to proceed with multi-disciplinary approach in which devoted crew of radiation oncologist, oral medicine and radiologist, oral surgeon, nurse, dietician, physical therapist, social worker and in few occasion, plastic surgeon, prosthodontist and psychologist should be incorporated.

The intention of dental management are listed below:

Pre-rt targets

• Remove probable source of infection.
• Guide patient about interim and deep roorted complications of RT.
• Impart preventive care.

During RT

• Impart supportive and medical care for oral mucositis
• Give treatment of oral candidiasis if required.
• Oversee the dryness of mouth and loss of taste.
• Prevent reduced mouth opening.

Long term after RT targets

• Oversee the dryness of mouth and taste dysfunction.
• Prevent and minimize trismus
• Prevent and treat dental caries
• Prevent and treat post radiation osteoradionecrosis
• Look for relapse for any abnormal growth.

The purpose of this study is to comprehend the oral complications attributable to RT to the patients who are going to receive the RT. To intervene pre RT dental screening of patient and impart required oral care to stabilize the oral diseases (if present). To provide medical care for oral complications attributed to the course of RT and after completion of RT to diminish patient discomfort.