Ear

Þ Other than skin cancers, tumors that present in the ear are rare. Þ Tumors that can arise along tympanic nerve or along blood vessels in the neck are considered a benign, highly vascular tumor such as: glomus jugulare or carotid body tumor. || One of the most common causes of ear cancer is exposure to the sun, with fair-skinned people being at higher risk. Additionally, temporal bone tumors are usually caused by a skin cancer that spreads to the bone. Ear cancers can also result from metastasis from another site altogether, and chronic skin infections have also been known to be a cause.1 || If the external canal is the area in question, oftentimes oozing drainage, pain, and pruritis are signs or symptoms.2 Pruritis is known as a sensation that causes the desire to itch.4 If the ear cancer is squamous cell, basal cell, or melanoma of the skin, the skin becomes indicative of the cancer with changes including lesions that appear as red patches for squamous cell carcinoma, pearly white or waxy for basal cell carcinoma, or brown or black lesions if it’s melanoma. 5 The ears continual exposure to the sun make them highly sensitive for the development of skin cancers. ||
 * **Epidemiolgy:** || Becky
 * **Etiology:** || Adam
 * **Signs & Symptoms:** || Megan
 * **Diagnostic Procedures:** || Kevin T

The two most common histology’s seen in cancer of the ear are basal cell carcinoma and squamous cell carcinoma.1 Basal cell carcinoma is most common in the external ear, whereas squamous cell carcinoma makes up approximately 85% of tumors involving the auditory canal, middle ear, and mastoid area. || Since the ear is relatively small with smaller structures within, there are only a few different sites for lymph node drainage.  Image showing the different locations of the ear lymph drainage.2 || The external ear is affected by a variety of skin cancers: squamous cell carcinomas and basal cell carcinomas. Of the two, squamous cell carcinoma is more likely to spread to surrounding tissues. These tumor cells can grow into the temporal bone and cause a variety of problems such as hearing and dizziness. Malignant melanoma is also a type of cancer that can affect the outer ear. Unfortunately, this type of cancer is very aggressive. The pattern of metastases of melanoma is unpredictable and can affect virtually any organ of the body.¹
 * Magnetic resonance imaging (MRI) can provide delineation of soft-tissue tumor margins, muscle infiltration, intracranial extension, and vessel encasement.1
 * Computed tomography to determine operability of tumor
 * Diagnosis is established by biopsy ||
 * **Histology:** || Erin
 * **Lymph node drainage:** || Spencer
 * Tragus and Auricle – The lymphatic vessels of these structures drain into the superficial parotid lymph nodes.1
 * Middle Ear and Mastoid Antrum – The lymphatic’s of these structures pass into the parotid nodes and the upper deep cervical lymph nodes.1
 * Inner Ear and Eustachian Tubes – There is no lymph drainage for this portion of the ear.1
 * **Metastatic spread:** || Pablo



Acoustic neuromas are benign tumors that grow in the inner ear. Although they do not metastasize, if they are allowed to grow they can then press on the vestibular cochlear nerve and cause severe pain.¹ || __Grade__ GX--Grade cannot be assessed(Undetermined grade) G1--Well-differentiated (Low grade) G2--Moderately differentiated (Intermediate grade) G3--Poorly differentiated (High grade) G4--Undifferentiated (High grade) ||||  ||
 * **Grading:** || Becky   --Tumor grading is used to classify the abnormal cells under the microscope.  **The American Joint Commission on Cancer recommends the following guidelines for grading tumors.** 1

Currently, there is no staging system for cancers of the ear. However, there has been a proposed system that is as follows:2
 * **Staging:** || Adam

T1 - Tumor limited to the EAC without bony erosion or evidence of soft-tissue involvement. T2 - Tumor with limited EAC bone erosion (not full thickness) or limited (<0.5cm) soft-tissue involvement. T3 - Tumor eroding osseous EAC (full thickness) with limited (<0.5cm) soft-tissue involvement, or tumor involving the middle ear and/or mastoid. T4 - Tumor eroding the chochlea, petrous apex, medial wall of the middle ear, carotid canal, jugular foramen, or dura, or with extensive soft-tissue involvement (>0.5cm), such as involvement of the TMJ or styloid process, or evidence of facial paresis.

N status Involvement of lymph nodes is a poor prognostic finding and automatically places the patient in an advanced stage (i.e. stage III (T1N1) or stage IV (T2, T3, and T4, N1) disease).

M status Distant metastasis indicates a very poor prognosis and immediately places the patient in the stage IV category. || Both necrosis of the cartilage of the external auditory canal and osteoradionecrosis of the temporal bone are anticipated side effects of radiation therapy.2 If 60-65 Gy is administered to the ear than a 4-10% chance of bone necrosis can be expected, and the risk increases with the increase of tumor size larger than 4cm.2 ||
 * **Radiation side effects:** || Megan
 * **Prognosis:** || Kevin Tsai


 * Large lesions involving the middle ear and lesions with extension into the temporal bone are most difficult to treat
 * 7th nerve palsy associated with middle ear tumor indicates poor local control ||
 * **Treatments:** || Erin The two most common treatment options are surgery and radiation therapy.1

__ Radiation Therapy __
 * Early stage cancer can be treated using electron beams or orthovoltage1
 * Interstitial irradiation (Ir-192) can also be used for lesions >4cm
 * Tumors involving the pinna (external ear) –
 * Electron beams or orthovoltage
 * Small, superficial lesion should have ~1cm margin
 * More extensive, large lesions should have ~2-3cm margin (SEE FIGURE)
 * 180-200cGy per fraction to prevent cartilage necrosis
 * Total dose of 65Gy over 6.5 weeks to achieve adequate tumor control




 * Large lesions of the external auditory canal –
 * Can be treated with radiation alone or combined with surgery1
 * Treatment fields should include the entire ear & temporal bone with ~3cm margin
 * Volume treated should also include the ipsilateral preauricular, postauricular, and subdigastric lymph nodes


 * Extremely advanced, unresectable tumors –
 * Treated with high energy (16-20MeV) electron beam therapy, either alone or mixed with photons (4-6MV). Wedged pair may also be used1
 * Total dose of 60-70Gy over 6-7 weeks

Most patients receiving radiation therapy treatment can be immobilized using an aquaplast mask.

__ Surgery __ Tissue dose associated with 5% injury rate within 5 years.3 - Ear - Eye - Cornea: 5000cGy – Blindness - Lens: 500cGy – Blindness - Brain: 5000-6000cGy – Infarction/Necrosis - Salivary Gland: 5000cGy – Xerostomia - Spinal Cord: 4500cGy – Infarction/Necrosis - Oral Cavity: 6000cGy – Ulceration || <span style="color: #ff0300; font-family: Arial,Helvetica,sans-serif;">1. Chao, K, Perez, C, Brady, L. Radiation Oncology Management Decisions. 3rd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2002. <span style="color: #ff0300; font-family: Arial,Helvetica,sans-serif;">2. Lymph Node Neck Pain. Pain Neck Web Site. http://www.painneck.com/lymph-nodes. Accessed June 4, 2013. <span style="color: #ff0300; font-family: Arial,Helvetica,sans-serif;">3. Hand C, Kim S, Waldow S. Overview of Radiobiology. In: Washington C, Leaver D, eds. Principles and Practice of Radiation Therapy. 2nd ed. St Louis, MO: Mosby-Elsevier; 2004:55-84. <span style="color: #ff0300; font-family: Arial,Helvetica,sans-serif;"> 1. Tumor Grade. Medicine Net.com Web site. []. 2010. Accessed June 4, 2013.
 * Surgery is recommended if a lesion has invaded cartilage of the ear or extends medially into the auditory canal1
 * For tumors involving the middle ear or temporal bone, mastoidectomy or lateral, subtotal, or total temporal bone resection may be done
 * Prophylactic neck dissection - recommended for lesions >4cm or for those with cartilage invasion because of the increased risk of nodal spread
 * Local Excision – with 1cm margin between the lesion & the tympanic membrane for lesions of the outer part of the auditory canal (as long as there is no radiographic evidence of invasion of the mastoid)
 * Partial temporal bone resection – may be necessary when the tumor involves the bony auditory canal & impinges the tympanic membrane (but does not involve the middle ear or mastoid
 * Radical surgery & post-operative radiation can be used for more advanced lesions of the external auditory canal & lesions in the middle ear and mastoid. ||
 * **TD 5/5:** || <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif;">Spencer
 * <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif;">Middle: 5000cGy – Serous Otitis
 * <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif;">Vestibular: 6000cGy – Meniere Syndrome
 * <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif;">Retina: 5500cGy – Blindness
 * **References:** || <span style="color: #0040ff; font-family: Arial,Helvetica,sans-serif;">Pablo

1. Ear and Temporal Bone Cancer. Cedars-Sinai Web Site. http://www.cedars-sinai.edu/Patients/Health-Conditions/Ear-and-Temporal-Bone-Cancer.aspx. Accessed June 6, 2013. 2. Chao KS, Perez CA, Brady LW. Radiation Oncology Management Decisions. 3rd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2011.

1. Gunderson LL, Tepper JE. Clinical Radiation Oncology. 2nd ed. Philadelphia, PA. 2007. 2. Chao KS, Perez CA, Brady LW. Radiation Oncology Management Decisions. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2002:187 4. Wikipedia. Itch. Last modified May 20, 2013. []. Accessed June 5, 2013. 5. Livestrong website. Types of Skin Cancer and Pre-Cancer Cells Found on the Ear. March 28, 2011.[]. Accessed June 5, 2013. 1. Chao KS, Perez CA, Brady LW. Radiation Oncology Management Decisions. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2002:183-187.

1. Chao KS, Perez CA, Brady LW. Radiation Oncology Management Decisions. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2002:183-187. || Back to Week 2