Oncological Management of a Patient with Carcinoma of the Larynx - Case Study Example

Table of Contents EPIDEMIOLOGY: 2 ETIOLOGY: 2 HISTOLOGY: 3 PRESENT SIGN AND SYMPTOMS: 4 DIAGNOSIS: 4 METHODS OF SPREAD AND STAGING: 5 ONCOLOGICAL MANAGEMENT OF THE DISEASE: 6 RADIOTHERAPY: (PRETREATMENT PREPERATION AND LOCALIZATION) 9 DOSE LIMITING STRUCTURES: (IN TREATMENT VOLUME AND THEIR DOSES) 10 DISEASE SIDE EFFECTS AND DAILY MANAGEMENT: 11 REFRENCES: 12 EPIDEMIOLOGY: No specific data regarding vocal cord cancer is obtained; following contains an epidemiological data of the laryngeal cancer as vocal cord cancer covers approximately half of the laryngeal cancers. Apart from skin cancer, the most common cancer of head and neck region is the larynx cancer. Larynx cancer carries about 2% of the total cancer risk. A study that worked on the data of the year 1973-1998 provides us with the information that out of all the cases of larynx cancer reported about 51% remain localized, 29% were having limited spread and 15% of the cases were of metastasis. The cases of glottis carcinoma were more as compared to the cases of supraglottis carcinoma with a ratio of about 3:1. (Mendenhall et al., 2014) Males are more frequently affected than females with a ratio of about 5:1 but risk is increased for the women who smoke. The incidence of laryngeal cancer is about 5 in 100,000 women. (Health.am, 2014). In UK , laryngeal cancer is about 1% of all the new cancer cases in males and about 0.3% in females. In the year 2010, 2,337 new cases of laryngeal cancer were reported out of which 1930 were males and rest of them were females i.e. 83 % males and 17 % females. (Cancerresearchuk.org, 2014) ETIOLOGY: The chances of larynx cancer increased with a history of cigarette smoking and the chances further increased with increased number of cigarettes per day. The risk of smoking associated cancer in respiratory and alimentary system in ex-smokers decreases after 5 years of smoking cessation and after 10 years it becomes equivalent to the risk for non-smokers. Alcohol is also a major risk factor when it is used in high quantity .i.e., more than four drinks per day. Otherwise, it’s a moderate risk factor. The risk is also increased when alcohol and tobacco are used simultaneously(Chera & Amdur et al.,2010). Malnutrition in combination with alcohol use can is also a significant risk factor (Sciencedirect.com, 2014).Races do not affect the occurrence rate of larynx cancer (Health.am, 2014). . Larynx cancer accounts for less than 1% of all the malignant cancers. The occurrence rate is quite higher in the elderly (fifties, sixties and seventies) and commonly it is quite rare in young (Health.am, 2014). People under forty years of their age are not commonly affected. (Cancer, 2014) A positive family history doubles the risk and chance of happening is also increased up to three folds in immunological disorders like HIV. People with recent organ transplantation and who are on an immunosuppressive drug therapy are having a twofold increased risk of laryngeal cancer (Cancer, 2014).Minor risk factors include HPV, HSV, oropharyngeal reflux (acid reflux), exposure to silica, polycyclic aromatic hydrocarbons etc (Sciencedirect.com, 2014). The patient of the following case study is a male, in his fifties and has ceased smoking just 9 months ago. Before abstention he was a chronic smoker and also a chronic alcohol user. So he is definitely at a risk of developing laryngeal cancer. HISTOLOGY: The early stages of vocal cord cancer represent a stage containing epithelial lesions,abnormalities in the cell internal structure like increased nucleus to cytoplasm ratio etc. At this stage the basal membrane remains intact. Examination with endoscope reveals various aspects at this stage. The differentiation between red and white laryngitis can be performed. Red laryngitis could also be of various forms like hyperemic laryngitis, hypertrophic laryngitis or pseudo-myxomatous hypertrophic laryngitis. Similarly, white laryngitis could of various forms like white exophytic, wharty plague, leukoplakis that is not sharply contoured. At this stage the histological examination may reveals a hyperplasia or carcinoma in situ.As the progression continues, the carcinoma in situ or simple hyperplasia may leads to invasive squamous cell carcinoma. The biopsies taken are usually superficial, so the histological examination is quite difficult. These tumors do no undergo metastasis but they do develop in to malpighian carcinomas. These are usually localized and can affect the neighboring cells. (Sciencedirect.com, 2014) The clinical examination of the patient in the following case by the help of an endo scope showed lesions on the right vocal cord while both of the vocal cords are still mobile. CT scan of the head and neck area demonstrated a 2cm lesion which is confined to the right vocal cord. So, histological examination showed him to be a casualty of invasive squamous cell carcinoma. PRESENT SIGN AND SYMPTOMS: Thepatient of the case under consideration presented to the GP with complains of cough and hoarseness of voice. He was treated with a course of anti biotic which did not reveal his symptoms. He was given a second course of antibiotic which apparently relieved the symptoms but the hoarseness persists. He is also having poor respiratory function due to COPD for the past year, worsening with pneumonia and chest infections. Thoracic examination showed hyperinflation, wheezing, decreased breath sounds and hyper resonance on percussion and prolonged examination(Schultz, 2011). DIAGNOSIS: If a person’s feels hoarseness or any kind of change in his voice that lasts for more than two weeks then he or she must report to a doctor, as it may be an indicative of laryngeal cancer. When a patient reports with such complain then the physician along with the regular check up also examine the vocal cords. Such examination is basically focusing at the internal structure of vocal cords and is done either with help of the long handled mirror which is inserted in the body by the help of the throat called indirect laryngoscopy or with the help of lighted tube (flexible) which is inserted in the body via mouth or nose called direct laryngoscopy. The use of light in case of direct laryngoscopy provides a clear picture of the area and helps further in diagnosis. (Uchospitals.edu, 2014) The doctor may ask the patient to produce specific sounds so that the doctor can examine the vocal cords when they are in action. The video recording of the whole procedure is usually made in order to facilitate the doctor later on. By these procedures the doctors usually diagnose most cases of laryngitis, vocal cord nodules or the polyps. While in certain other cases the doctor may suggest an acoustic analysis which consists of series of different steps that are aiming to determine the voice quality which may include its pitch, range and intensity. The use of acoustic tests is usually carried out when the vocal cords under paralysis or a surgical procedure is to be performed after wards. These tests are also very helpful to the doctor in determining then improvement after treatment.In most of the instances appearance of larynx cancer is much similar to the non cancerous growth or any kind of ulceration, so the doctor also usually recommendsbiopsy. Some other tests like computed tomography (CT) scans can additionallybe performed in cases of vocal cord or paralysis or cancer in order to confirm the diagnosis. (Drugs.com, 2014)The complete examination of aerodigestive tract should be carried out in order to examine the primary or the secondary tumor. A recommendation of the diagram with date is also provided. (Sciencedirect.com, 2014). In the following case the CT scan of the patient reveals that he is having 2cm lesion in the right vocal cord. Biopsy also demonstrates the invasive squamous cell carcinoma; therefore he is stagged as T 1 N 0 superficial squamous cell carcinoma of the right vocal cord(Koonce & Garas et al., 2012). METHODS OF SPREAD AND STAGING: Cancer staging is a method to describe different aspects of severity of cancer in a patient. Different stages in this staging system are relying on the size of the cancer and/or the extent to which the cancer has spread in the body to different other regions from the point of its origin. Once the stage of the patient’s cancer is identified then it becomes a very helpful tool in determining the treatment regimen of the patient as well the prognosis. (Cancer.gov, 2014) American Joint Committee on Cancer (AJCC) and Union for International Cancer Control (UICC) approved a system of staging of cancer called TNM system. This method depends on the size of the original tumor T, the lymph nodes involvement N and the extent of metastasis M (Cancer.org, 2014). This method explains T= TUMOR N= LYMPH NODE M= METASTASIS TX = no tumor NX=cannot be evaluated MX= cannot be evaluated T0 = no primary tumor N0=no lymph node invlovement M1 = no metastsis T is = carcinoma in situ N1, N2, N3 = different stages of lymph node invloment M 2= metastasis occured T1, T2, T3, T4 = depends on tumor size and spread In its 7th edition, 2009 the AJCC and UICC explain the staging with respect to vocal cord cancer which is based on the prognosis of the tumor (T). (Sciencedirect.com, 2014). Stages Features Tis Localized carcinoma i.e., carcinoma in situ T1 T 1a T 1b Limited to vocal cords only , vocal cords mobile Of only one fold Of two folds T 2 Extension of tumor to subglottis or supra glottis level Vocal cords may or may not mobile T 3 Fixation of vocal cords. T 4 Invasion of thyroid cartilage Invasion of paravertebral space. The patient described in the particular case is having T1 cancer due to the involvement of only one sided vocal cords. He is diagnosed to be N0 because no lymph node involvement is found on examination. ONCOLOGICAL MANAGEMENT OF THE DISEASE: Cancer treatment is always been a point of great interests for the medical professionals around the world. Different treatment methods are available for the different types of cancers and for the different stages of cancers. Similarly, for the treatment of squamous cell carcinoma a variety of treatment strategies are now available. A patient can be offeredwith a wide range of treatment methodologies which may depend upon his health, age, stage of the cancer, extent of metastasis or the patient’s economical background. But in all the cases the ultimate goal of treatment is the preservation of the organ and organ’s function. (JENCKEL and KNECHT, 2013) The treatment methodologies employed are the use of surgical techniques or the utilization of the conservative methods (radiotherapy, chemotherapy, targeted molecular therapy). In past, the gold standard for the advanced laryngeal cancer was laryngectomy but now the approach has changed. Now more emphasis is given to increase the quality of life of the patient. This can be done by preserving the organ and most importantly by preserving the function of the organ. First of all we will discuss the surgical treatment of the patient suffering with squamous cell carcinoma of the vocal cords. In past total laryngectomy was the only option for treating a laryngeal cancer but this cause permanent tracheostoma and damage to the function of vocal cords. So the modern techniques do not consider it a good option and never goes for it unless laryngectomy remains the only option. But in some situations the use of laryngectomy is mandatory. According to Silver et al, laryngectomy is still an important method in each perspective i.e. as an initial treatment or as a salvage treatment methodology. There is conditions e.g. unreliable patient, patient in an undeveloped country, or a patient in an area where multimodality treatment and follow up may not be available. While in some instances the patients himself is not willing for the lengthy trial of chemo radiation and follow up. On the other hand the issue of cost effectiveness is also of importance. Sometimes cost is the only responsible factor when the decision for laryngectomy is made. Total laryngectomy is the method of choice in the recurrent laryngeal cancer cases, when the patient is not responsive to the chemotherapy, when chemotherapy cannot be employed due to the co morbidities. The second surgical method employed is the partial laryngectomy. It is an open transcutaneous technique and is used when the larynx cannot be overviewed using a laryngoscope. It can be used for the treatment of early and advanced laryngeal cancer (Tong & Au et al., 2012). It is not used frequently for the treatment of untreated early stage cancer but it can be used for the salvage surgery especially when the chemo therapy and radio therapy did not work. Another method is vertical partial laryngectomy. It is the pioneer of the surgeries that accounts for organ preservation. This type of surgical treatment caries a lot of importance and it is called as the vertical partial laryngectomy because a vertical incision is made in the endolarynx. Other surgical methods involved are supraglottic laryngectomy and Supracricoid partial laryngectomy, Transoral laser surgery which are having benefits in particular situations. (JENCKEL and KNECHT, 2013) European Laryngological Society provides classification of the cordectomy , a surgical technique most commonly employing the use of CO2 laser. It is mostly indicted T 1s, T 1a, T 1b or T 2. (Sciencedirect.com, 2014). The methods other than surgery (conservative treatment) include radiotherapy, concurrent chemo-radiotherapy and induction chemotherapy and target therapy. High energy x-rays, gamma rays or particles are used as radiation therapy to kill cancer cells. Radiation therapy can be employed at various stages in treatment of laryngeal cancer. It can be used in patient whose health is not good for surgery, it can be used for the patient whose surgery is already performed but there are small areas of cancer or can be used for the treatment of early stage laryngeal or hypolaryngeal cancer. It can also be used to relieve the symptoms associated with cancer like pain, trouble swallowing etc Two common types of radiation therapy includes; external beam radiation therapy and three dimensional conformal radiotherapy (3D-CRT). The former is similar to X-ray but the beam is of high intensity. 3D-CRT utilizes MRI to accurately map the tumor and then the target area is exposed to radiation from different angles. One of the latest techniques is the Intensity modulated radiation therapy (IMRT). This technique is step ahead to three dimensional therapies. It utilizes the machine which is controlled by a computer that guide the machine to move around the patient as the radiation is made to fall over the target area. In addition the intensity of the beam can also be controlled to limit the dose that is reaching to the target as well as to the nearby organs (Cancer.org, 2014). The use of radiotherapy is of advantage in patients having small tumors of larynx. The primary goals like maintenance of the organ function and the achievement of the local control is achieved especially in case of early glottis tumors (T 1a). This effect is more prevalent in the patients with preserved vocal cord function. The advanced laryngeal cancers can also be treated with radiotherapy but there are no studies that compare the non surgical treatment (radiotherapy etc) with the surgical treatment strategies for the advanced cancers(Levendag & Teguh et al., 2011). Studies have shown that concurrent chemo- radiotherapy and induction chemotherapy are superior to the sequential therapy or radiotherapy alone when applied to stage III or stage IV cancer(Barrett & Dobbs et al., 2009). Epidermal growth factor receptors (EGFR) are the integral component of the cell epithelium and their concentration are found to be very high in the squamous cell carcinomas, especially of neck and head region. Various types of molecules are designed which aim to inhibit these proteins and this type of approach is called target therapy. These may include monoclonal antibiotics like cetuximab and anti- sense oligonucleotides. (JENCKEL and KNECHT, 2013). When the comparison between radiation therapy and endoscopic surgery is made then these are almost same in local control, laryngeal protection and survival in case of T1 vocal fold cancer. But radiation therapy has additional advantages of better vocal quality and laser cordectomy has additional advantages of short hospital stay, lower cost and anatomopathological control. (Sciencedirect.com, 2014). In this particular case, patient’s vocal cord cancer is diagnosed for the first time and the cancer has not spread and is not undergone metastasis. He is thus a suitable candidate for radiotherapy. RADIOTHERAPY: (PRETREATMENT PREPERATION AND LOCALIZATION) Careful planning is performed before radiotherapy. The planning involves the investigation of how much radiation does the patient need and exactly at which area of his body. The particular area of the body which is exposed to the radiations is called as the radiation field. The radiations are made to fall over the radiation field at different angles. This allows the radiations to meet at a particular point which is the area receiving maximum dose of the radiations. This maximum dose of radiations is referred to as target volume of the radiation. The planning focuses on the point that during the procedure the surrounding healthy cells shall receive the minimum radiation dose and thus are less affected. Certain radiographic techniques are used now a day’s which made the radiations to fall according to the shape of the tumor. These may include conformal or intensity modulated radiotherapy. Certain other techniques are targeting the moving tumor such as due to breathing e.g. stereotactic radiotherapy. Before the actual radiotherapy a clinical oncologist may perform CT SCAN, MRI SCAN, or X-ray scan in order to obtain maximum knowledge about the tumor of the patient. This enables him to determine the correct dose of the radiation in order to prevent the healthy cells(Gelletti & Freni, et al., 2012). During planning the patient is made to lie on quite a hard couch. The patients are asked to remain still so that his body position can be accurately recorded. This helps the radiographer to make sure that during the treatment procedure the person would lay in the accurate position. Once the radiotherapy is planned, pin point ink marks are placed on the body to indicate the area receiving the radiotherapy. When the radiotherapy of the head and neck area is performed as in the following case of squamous cell carcinoma of vocal cords then the patient is asked to wear a mould or a shell to keep him still during the whole procedure. (Cancer, 2014) DOSE LIMITING STRUCTURES: (IN TREATMENT VOLUME AND THEIR DOSES) In case of the T 1 and small T 2 glottic tumors, radiation therapy is indicated. Different types of techniques are adopted for different types of tumors. In case of the tumors that are limited to the glottis area the radiation is focusing on the target volume and involve the use of 5 x 5 cm or 6 x 6 cm opposing parallel fields. In case of the supraglottic tumors the radiations also made to fall on the lymph node areas II, III and IV(Czecior & Orecka, 2012). Similarly, in case of subglottic tumors the lymph nodes VI a and b are also involved. The dose of the radiation depends on the stage of tumor and is usually ranges from 60 to 70 Gy. 66 Gy for T is and T1 tumors 70 Gy for T2 tumors In case of the lymph nodes areas 50 Gy is the recommended dose in prophylactic radiotherapy and 60-70 Gy in case of the clinically invaded areas. (Sciencedirect.com, 2014). It has been found that the use of radiation to treat head and neck cancer (laryngeal cancer constitutes major % of head and neck cancer) can cause severe side effects. These side effects may include dysphagia and aspiration along with many others. But these can be minimized by using the IMRT techniques. According to (Redjournal.org, 2014), the utilization of IMRT technique can lower the incidence or severity of these side effects by sparing the structures which lie near to them like pharyngeal constrictors. DISEASE SIDE EFFECTS AND DAILY MANAGEMENT: The most important impact of vocal cord cancer on quality of life of a patient is the disturbance of his voice. Patients with vocal cord cancer not only presents with impaired voice but even after treatment the problem persist in one way or the other(Koulouslias & Zygogianni, et al.,2013). Thus the patient should learn about how to talk without putting stress on his vocal cords. Consultation with a voice therapist is recommended. One of the important considerations is avoiding the key factors that can cause irritation to the area e.g. the acid reflux, smoking cessation and decreased consumption of alcohol, caffeine, fatty foods etc. If a person is using inhalational corticosteroids for treating asthma or others as in the following case the patient is suffering with COPD then it can help in preventing vocal cord muscle weakness. But for this purpose the device used should be able to carry the medicine droplets to the target area and thus preventing their settlement in throat, trachea and small areas of upper respiratory tract causing further side effects.  (Drugs.com, 2014) REFRENCES: Barrett, A., Dobbs, J., & Roques, T. (2009). Practical Radiotherapy Planning Fourth Edition. CRC Press. London: Hodder and Arnold. Cancer, R. 2014. Risks and causes of laryngeal cancer : Cancer Research UK : CancerHelp UK. 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