What are the causes of oral cancer

Tobacco consumption is the most common cause for oral cancer. It is consumed in various forms. It may be chewed or it may be smoked. Chewed tobacco is used in various forms such as mawa, khaini, pan, pan masala etc.  It may be smoked in the form of bidi, Hukkah, cigarette etc. Gutka and areca nut or supari also cause mouth cancer and rampantly used in some part of our country. All these forms are harmful and cause cancer.

Alcohol is another cause for oral cancer especially floor of mouth cancers. Risk of cancer is increased many folds when both tobacco and alcohol are consumed together.

Sharp tooth and ill fitting dentures causing repeated trauma can also cause oral cancer.

Poor orodental hygiene, HPV virus infection, dietary deficiencies are other causes of mouth cancer.

Can it be cured

Oral cancer can be cured if detected early. Hence early diagnosis and treatment is crucial for successful outcome. It is important to be aware of symptoms and warning signs of cancer so that treatment can be started on time.

Symptoms & Warning Signs

1. Non healing ulcer i.e. an ulcer which does not heal despite treatment
2. Any rough area inside mouth
3. Any growth that bleeds on touch
4. White patch or red patch inside mouth
5. Sudden fall of tooth
6. Change in size of dentures
7. Altered speech
8. Difficulty in eating
9. Pain at the back side of throat radiating to ear
10. Neck swelling
11. Skin ulcer or swelling over face

For more details kindly visit following videos by dr Shilpi Sharm:

https://youtu.be/A2uioDdoqto         10 Warning signs of Oral cancer  (Hindi)

https://youtu.be/YPfaQtX-ZFo           10 Warning signs of Oral cancer  (English)

https://youtu.be/THxIaDnU6mU   Symptoms of Mouth and throat cancer  (Hindi)

Diagnosis

Clinical Examination

Patient is examined clinically by the oncologist and extent of tumor is determined. Based on clinical examination finding further tests are ordered.

Biopsy

Biopsy is done to confirm the presence and type of cancer. It is often done as an out patient procedure. In this, a small piece from the growth is taken and sent for pathological examination. Biopsy is essential before starting cancer treatment.

Imaging

Imaging is done to know tumor extent in all dimensions including deeper tissues. CT scan, MRI or PET CT is done based on tumor location, site and size.

Staging

Tumor is staged based on clinical and radiological findings. It is staged as early stage (stage I/II ) or advanced stage (stage III/IV).

Treatment

Treatment of oral cancer is primarily by surgery. Radiation therapy alone or along with chemotherapy is required in late stages.

Surgery

Surgery includes complete excision of tumor along with a safety margin of normal tissue all around the tumor. Extent of surgery depends on tumor size and involvement of adjoining  structures. Surgery includes excision of main tumor and removal of draining lymph nodes of neck called as neck dissection.  

Radiotherapy

Radiotherapy is used mainly in advanced cases after surgery so that chances of recurrence can be reduced.

Chemotherapy

In oral cancer, chemotherapy is mainly used for the treatment of advanced stage IV cancers where it is used along with radiotherapy after surgery. Chemotherapy alone is generally used in cases where either the tumor is very advanced and has spread to distant areas such as lung, liver or bone or it has come back again and either surgery or radiotherapy can not be given. Intent of treatment in this situation is palliative that means chemotherapy is not going to completely remove the disease but is given to slow the tumor growth.

Targeted therapy

In this therapy, drugs are used which target specific parts of cancer cells such as proteins or genes involved in tumor growth. These are used along with chemotherapy in advanced cases where surgery and radiation therapy are not an option.

Immunotherapy

Immunotherapy is a type of therapy which acts on body’s immune system to fight cancer. For oral cancer it is used in advanced cases where surgery can not be done and radiotherapy is not possible. Immunotherapy is given either alone or along with chemotherapy.

Follow up

It is very important to be in regular follow up after cancer treatment. This is done to detect future recurrences at the earliest. At each follow up visit, patient is examined clinically by oncologist. Imaging may be required based on tumor stage and symptoms. Follow up is done at 2-3 months for initial 2 years, 3-6 monthly for next 3 years and annually thereafter.

Dr Shilpi Sharma has following publications on oral cancers: (Journals and Book Chapters)

1. ICMR – Task force guidelines on tongue cancer. 2014. Published on ICMR Website. pdf (icmr.nic.in)
2. D’Cruz AK, Sharma S, Rath GK et al. Indian Council of Medical Research (ICMR) Consensus Document for the Management of Tongue Cancer. Indian Journal Of Medical And Pediatric Oncology. 2015;36(3):140-45.
3. Sayed SS, Sharma S, Rane P, Vaishampayan S, Talole S, Chaturvedi P et al. Can Metastatic Lymph Node Ratio (LNR) Predict Survival in Oral cavity cancer Patients? Journal of Surgical Oncology 2013;9999:1–8.
4. Sawant S, Dongre H, Singh AK, Joshi S, Costea DE, Mahadik S, Ahire C, Makani V, Dange P, Sharma S, Chaukar D, Vaidya M. Establishment of 3D Co-Culture Models from Different Stages of Human Tongue Tumorigenesis: Utility in Understanding Neoplastic Progression. PLoS One. 2016 Aug 8;11(8):e0160615.
5. More Y, Sharma S, Chaturvedi P, D’Cruz AK. Gingivobuccal mucosal cancers: resection to reconstruction. Curr Opin Otolaryngol. Head Neck Surg. 2014;22(2):96-100.
6. SawantS ,Gokulan R, Dongre H, Vaidya M, Chaukar D, Prabhash K, Sharma S et al. Prognostic role of Oct4, CD44 and c-Myc in radio-chemo resistant oral cancer patients and their tumourigenic potential in immunodeficient mice”. Clinical Oral Investigations. 2016;20:43–56.
7. Sawant S, Dongre H, Ahire C, Sharma S, Jamghare S, Kansara Y, Rane P, Kanojia D, Patil A, Chaukar D, Gupta S, D’Cruz A, Vaidya M, Dongre P. Alterations in desmosomal adhesion at protein and ultrastructure levels during the sequential progressive grades of human oral tumorigenesis. Eur J Oral Sci. 2018 Aug;126(4):251-262.
8. Sawant SS, Dongre H, Ahire C, Sharma S,et al. A nomogram for predicting the risk of neck node metastasis in pathologically node-negative oral cavitycarcinoma. Oral Dis. 2017 Nov;23(8):1087-1098.
9. Laskar SG, Chaukar D, Deshpande M, Chatterjee A, Hawaldar R, Chakraborty S, Sharma S, et al.Phase III randomized trial of surgery followed by conventional radiotherapy (5 fr/Wk) (Arm A) vs concurrent chemoradiotherapy (Arm B) vs accelerated radiotherapy (6fr/Wk) (Arm C) in locally advanced, stage III and IV, resectable, squamous cell carcinoma of oral cavity- oral cavity adjuvant therapy (OCAT): Final results (NCT00193843). J ClinOncol 34, 2016 (suppl; abstr 6004) (ASCO- Oral abstract).
10. ChaukarDA, Sharma S, Deshmukh A, Juvekar SL, Arya S, Kane SV, et al. To study the radiological accuracy in determining the tumor thickness and depth of invasion for gingivobuccal complex cancers. Oral Oncology. 2013; 49,Suppl 1:S35–36
11. Sharma S, Sayed S, Rane P, Chaukar DA, Deshmukh A, D’Cruz AK. Cut Margin Status and Its Impact on Outcome in Cancers of Oral Cavity; S264:8^thAHNS , Toronto conference book
12. Sharma S, Chaturvedi P. Keratosis. International Journal of Head and Neck Surgery. 2010 ; 1(3): 193-194

    Book Chapters

    International

13. Sharma S, Dandekar M, Chaukar D. Kanker Tiroid, Oral, Dan Kelenjar Saliva.Indonesia.1^st 2019. Diagnosis of oral cancer.
14. Dandekar M, Sharma S, Chaukar D. Kanker Tiroid, Oral, Dan Kelenjar Saliva.Indonesia.1^st 2019. Biology of oral squamous cell carcinoma.

    National

15. Surgery for cancer of buccal mucosa. Operative surgical oncology book, Tata Memorial Hospital, 2016