According to TNM classification, which of the following is the correct clinical classification of this tumor?

(A) T2 N1 M0
(B) T3 N1 M0
(C) T3 N2 M0
(D) T4 N1 M0
(E) T4 N2 M0

The correct response is Option D.

In this patient who has a 2.5-cm squamous cell carcinoma of the lateral floor of the mouth that is adherent to the adjacent mandible, as well as a 2-cm palpable lymph node but no evidence of distant metastases, the tumor is correctly classified as T4 N1 M0. The staging of squamous cell carcinomas of the oral cavity involves three descriptors: T, N, and M. The T descriptor is based on the diameter or surface area of the primary tumor. The N descriptor describes nodal status. The M descriptor indicates distance of metastasis beyond the neck. This staging criteria allows physicians to predict patient outcomes and choose appropriate therapy based on comparisons with patients in large studies.

A TNM classification table for squamous cell carcinoma of the oral cavity is shown below.

Status of Tumor (T)
TX - Primary tumor cannot be assessed
T0 - No evidence of primary tumor
Tis - Carcinoma in situ
T1 - Tumor 2 cm or less in greatest dimension
T2 - Tumor more than 2 cm but not more than 4 cm in greatest dimension
T3 - Tumor more than 4 cm in greatest dimension
T4 (lip) - Tumor invades adjacent structures (eg, through cortical bone, inferior alveolar nerve, floor of mouth, skin of face)
T4 - (oral cavity) Tumor invades adjacent structures (eg, through cortical bone, into deep [extrinsic] muscle of tongue, maxillary sinus, skin; superficial erosion alone of bone/tooth socket by a gingival primary tumor is not sufficient to classify as T4)

Status of Lymph Nodes (N)
NX - Regional lymph nodes cannot be assessed
N0 - No regional lymph node metastasis
N1 - Metastasis in a single ipsilateral lymph node, 3 cm or less in greatest dimension
N2 - Metastasis in a single ipsilateral lymph node more than 3 cm but not more than 6 cm in greatest dimension; or in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension; or in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension
N2a - Metastasis in a single ipsilateral lymph node more than 3 cm but not more than 6 cm in greatest dimension
N2b - Metastasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension
N2c - Metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension
N3 - Metastasis in a single ipsilateral lymph node more than 6 cm in greatest dimension

Status of Metastasis (M)
MX - Distant metastasis cannot be assessed
M0 -No distant metastasis
M1 - Distant metastasis

References
1. American Joint Committee on Cancer: Manual for Staging of Cancer. 4th ed. Philadelphia, Pa: JB Lippincott Co; 1992.
2. Cooper JS, Farnan NC, Asbell SO, et al. Recursive partitioning analysis of 2105 patients treated in Radiation Therapy Oncology Group studies of head and neck cancer. Cancer. 1996;77:1905-1911.

A 31-year-old man has pain and loosening of mandibular teeth associated with a rapidly expanding mass in that region. Histologic examination of a biopsy specimen shows osteogenic sarcoma. Which of the following is the most appropriate management?

(A) External beam radiation therapy
(B) Interstitial brachytherapy
(C) Chemotherapy
(D) Radical excision
(E) Radical excision followed by chemotherapy and radiation therapy

The correct response is Option E.

Radical excision remains the recommended primary treatment method for patients with osteogenic sarcoma, which is an aggressive, rapidly expanding mass often seen in the maxilla or mandible. However, adjuvant chemotherapy and radiation therapy have also been recommended as of late; clinical randomized trials of patients with osteogenic sarcoma have shown improved disease-free survival rates following chemotherapy and radiation therapy in patients with tumors affecting either the head and neck or the extremities. In addition, combination therapy is recommended because these tumors recur frequently.

The mean age of onset of osteogenic sarcoma is age 31 years; symptoms at initial presentation include jaw pain and loosening of teeth. Risk factors include fibrous dysplasia and retinoblastoma, as well as previous exposure to ionizing radiation or colloidal thorium dioxide (Thorotrast).

In patients who undergo surgical resection alone, five-year survival rates range from 23% to 35%.

References
1. Delgado R, Maafs E, Alferian A, et al. Osteosarcoma of the jaw. Head Neck. 1994;16:246-252.
2. Mark R, Sercarz JA, Tran L, et al. Osteosarcoma of the head and neck: the UCLA experience. Arch Otolaryngol Head Neck Surg. 1991;117:761-766.

Which of the following is the most common site of minor salivary gland malignancies?

(A) Buccal mucosa
(B) Floor of the mouth
(C) Lip
(D) Palate
(E) Tongue

The correct response is Option D.

Approximately 9% of all salivary gland tumors originate within the minor salivary glands; the palate is the most common site of origin, with 50% of all minor gland tumors occurring here. In contrast, only 15% of all minor salivary gland tumors originate in the lip, 12% in the buccal mucosa, and 5% in both the tongue and floor of the mouth.

Most minor salivary gland malignancies are classified histologically as adenoid cystic carcinomas, but other types can also be seen. The tumors affecting these glands are often smooth submucosal masses that are rarely associated with pain and numbness. Rapid tumor growth, pain, and ulceration are indicators of malignancy. Appropriate management of minor salivary gland tumors includes surgical resection with adequate margins, including any involved mucosa, muscle, or bone. Radiation therapy is recommended postoperatively for management of tumors with high-grade histologic features, positive surgical margins, perineural spread, deep invasion into muscle or bone, or lymph node metastasis.

References
1. Spiro RH, Thaler HT, Hicks WF, et al. The importance of clinical staging of minor salivary gland carcinoma. Am J Surg. 1991;162:330-336.
2. Yu GY, Ma DQ. Carcinoma of the salivary gland: a clinicopathologic study of 405 cases. Semin Surg Oncol. 1987;3:240-244.

A 64-year-old man develops a chylous fistula 10 days after undergoing left total parotidectomy and radical neck dissection for management of a parotid gland malignancy with metastasis to the ipsilateral neck. In addition to initiation of a medium-chain triglyceride diet, which of the following is the most appropriate management?

(A) Repair of the thoracic duct
(B) Closed suction drainage of the neck
(C) Radiation therapy of the neck and parotid bed
(D) Mediastinal exploration with ligation of the thoracic duct
(E) Surgical exploration of the neck with interposition of a pectoralis major myocutaneous flap

The correct response is Option B.

In this patient who has a chylous fistula, the most appropriate management is initiation of a medium-chain triglyceride diet and closed suction drainage of the neck. Chylous fistulas develop as a result of injury to the thoracic duct as it enters the jugular vein at the inferior region of the left neck; this finding is seen in as many as 4% of patients who have undergone radical neck dissection on the left. A medium-chain triglyceride diet will curb the flow of chyle into the region, while closed suction drainage will remove the existing chyle, allowing for closure of the fistula. Mediastinal exploration with ligation of the thoracic duct may be considered in patients who have refractory fistulas.

Repair of the thoracic duct is generally not performed initially. Radiation therapy should only be considered after closure of the fistula. Although interposition of a pectoralis major myocutaneous flap may help to seal the fistula, it should not be considered as a first-line treatment.

References
1. Johnson JT, Myers EN. Management of complications of head and neck surgery. In: Myers EN, Suen JY, eds. Cancer of the Head and Neck. Philadelphia, Pa: WB Saunders Co; 1996:693-711.
2. Shah JP. Cervical lymph nodes. In: Shah JP, ed. Head and Neck Surgery. London, England: Mosby-Wolfe; 1996:355-392.

A 68-year-old woman has had a slowly enlarging nodule on the right upper eyelid for the past eight months. Physical examination shows a dark purple 8-mm nodule on the eyelid; ipsilateral parotid and cervical nodes can be palpated. Histologic examination of a biopsy specimen of the lesion shows uniform sheets of small oval cells within the deep epidermis and subcutaneous fat that have indistinct margins.

These findings are most consistent with

(A) basal cell carcinoma
(B) malignant melanoma
(C) Merkel cell carcinoma
(D) microcystic adnexal carcinoma
(E) squamous cell carcinoma

The correct response is Option C.

This patient has findings consistent with Merkel cell carcinoma, an extremely aggressive tumor most commonly encountered in the head and neck region of elderly women. These nodules are pink to deep purple in color and rarely ulcerate. Light microscopy will show dense sheets of oval cells with indistinct borders that invade the deep dermis, subcutaneous fat, and muscle while sparing the papillary dermis and epidermis. Some surgeons advocate the use of electron microscopy and immunohistochemistry because these lesions can be mistaken for metastatic oat cell carcinoma or poorly differentiated lymphoma. A biopsy specimen of the lesion will most likely stain positive for neuron-specific enolase.

Because 33% of affected patients will experience a local recurrence within one year of initial treatment and approximately 50% will ultimately develop nodal metastases, wide local excision with a margin of 2.5 cm to 3 cm is indicated. En bloc resection of involved nodes and postoperative radiation therapy are also recommended; chemotherapy and prophylactic nodal dissection are controversial treatment options. Long-term survival rates are poor; only 55% of patients diagnosed with Merkel cell carcinoma will survive for three years. Factors that are associated with a poor prognosis include male gender, early age at initial onset, and location of the tumor on the head, neck, or trunk.

Basal cell carcinomas are common slow growing tumors of the head and neck that can be pigmented or ulcerated. Because these tumors rarely metastasize, local excision with 5 mm margins is recommended.

Malignant melanoma is a highly aggressive tumor of brown pigmentation that often develops within an existing nevus. Exposure to ultraviolet radiation has been associated. Melanomas of the hands and feet are associated with a significantly worse prognosis than those of the arm and leg. Excision with wide margins is advocated for treatment of malignant melanoma.

Microcystic adnexal carcinomas are rare, flesh colored nodules involving the upper lip, nose, and periorbital regions in middle aged patients. Perineural invasion is almost always seen with this locally aggressive and often recurrent tumor. Ulceration and nodal metastases are rare. Appropriate management of microcystic adnexal carcinoma is Mohs' micrographic resection, including complete histologic examination of the tumor margins. Radiation therapy is ineffective.

Squamous cell carcinomas arise from the malpighian layer and have a strong association with actinic radiation. Cutaneous squamous cell carcinomas have a rough, ulcerated appearance and most frequently affect the head and neck region. The overall rate of metastasis is extremely low. Direct excision or radiation therapy are equally advocated as initial treatment. Recurrent lesions are treated with Mohs' micrographic resection.

References
1. Cook TF, Fosko SW. Unusual cutaneous malignancies. Semin Cutan Med Surg. 1998;17:114-132.
2. Hanke WC, Conner AC, Temofeew RK, et al. Merkel cell carcinoma. Arch Dermatol. 1989;125:1096-1100.
3. Mayer MH, Winton GB, Smith AC, et al. Microcystic adnexal carcinoma (sclerosing sweat duct carcinoma). Plast Reconstr Surg. 1989;84:970-975.
4. Mercer D, Brander P, Liddell K. Merkel cell carcinoma: the clinical course. Ann Plast Surg. 1990;25:136-141.
5. O'Connor WJ, Brodland DG. Merkel cell carcinoma. Dermatol Surg. 1996;22:262-267.
6. Shaw JH, Rumball E. Merkel cell tumour: clinical behaviour and treatment. Br J Surg. 1991;78:138-142.