222
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
MAY, 1976
Management of Parotid Neoplasms EARL BELLE SMITH, M.D., F. A. C.S., Director of Surgical Education & Research, St. Francis General Hospital, Pittsburgh, Pennsylvania
DAROTID neoplasms present
a
unique
management problem1-'3 in that the majority are benign. The recurrence rate can be high if management is not appropriate. Sacrifice of the facial nerve results in a deformity which demands adequate treatment and fear of facial nerve injury may lead to inadequate cancer surgery and a high recurrence rate. The objectives of this study are to review general principles of parotid gland surgery and make a comparative analysis of our experiences at St. Francis General Hospital with other series. ANATOMY
Although anatomical relationships of the facial nerve to the parotid gland are common knowledge, the following points should be emphasized: 1) the facial nerve leaves the skull through the stylomastoid foramen anterior to the mastoid process of the temporal bone and enters the parotid gland; 2) the facial nerve divides into temporofacial and cervicofacial trunks from which terminal branches arise; and 3) the parotid gland is arbitrarily divided into superficial and deep lobes by the facial nerve and its branches. PATHOLOGY
The following classification is generally accepted to outline the behavior of parotid neoplasms and their management. Seventy-five per cent of parotid neoplasms are benign and are classified as: 1) mixed tumor; 2) Warthin's tumor; 3) mucoepidermoid tumor; 4) oncocytoma; 5) benign lymphoma; and 6) papillary cystadenoma. Benign mixed tumor is the most common benign neoplasm. The mixed tumor and mucoepidermoid tumor show distinct tendencies
for recurrence following surgery. Twenty-five percent of all parotid neoplasms are malignant. The malignant parotid tumors are subdivided into low and high grade. Low grade neoplasms are characterized by a prolonged clinical course, progressive local growth and regional distant metastases. These neoplasms are as follows: 1) malignant mixed tumor; 2) mucoepidermoid carcinoma; 3) adenocystic carcinoma; and 4) acinar cell carcinoma. The adenocystic carcinoma invades the seventh nerve early and spreads along the course of lymphatics. High grade tumors are characterized by a short clinical course, rapid local infiltration, early regional and distant metastases. The squamous cell and undifferentiated varieties fall into this category. PREOPERATIVE EVALUATION
Clinical Diagnosis. The clinical diagnosis of parotid neoplasm is not always simple. It is often confused with cervical and facial lymph nodes and cysts. Generally, it is a firm, mobile and painless lump in front of the ear, below the ear lobe or just behind the angle of the mandible. Benign tumors are generally firm, slow growing, mobile and well-defined. Malignant tumors are hard in consistency with a rapid growth rate, fixity to adjacent structures and facial paralysis. Histological Diagnosis. The true nature of parotid neoplasm can be ascertained only by histological examination. The best biopsy technique is excisional biopsy. Needle biopsy has little place in diagnosis of parotid neoplasm. It often results in seeding of the tumor. In addition, the amount of tissue obtained is inadequate for pathological analysis.
Vol. 68, No. 3
Parotid Neoplasms TREATMENT
223
Various modalities of treatment are radiotherapy and surgery. Radiotherapy has not been established as definitive primary therapy. It is used as adjuvant therapy. Surgical treatment of parotid neoplasms is indicated because of their resistance to radiotherapy. The objectives of parotid gland tumor surgery are to completely remove the neoplasms and preserve the branches of the facial nerve.
as it passes in front of the facial vein and 1.5 cm lateral to mastoid process. In the peripheral method, the peripheral branches of the facial nerve are identified anterior to the parotid gland and traced to the trunk of the facial nerve. Dissection between parotid gland and facial nerve should be blunt and diathermy should not be used. Superficial lobectomy is performed by blunt dissection and frozen section is obtained.
Table 1. AGE INCIDENCE OF PATIENTS WITH
Table 3. TYPES OF PAROTID NEOPLASMS
PAROTID NEOPLASMS Type of Neoplasm Age
No. of Patients
Percentage
7 14 1
32 65 3
22
100
17-40 yr. 40-60 yr. Above 60 yr. Totals
Technique. Basically, the technique of parotid surgery is the same whether the tumor is benign or malignant. Wide excisional biopsy, i.e., superficial lobectomy, is recommended in all patients for tissue diagnosis. Endotracheal anesthesia is utilized exclusively and the facial nerve should not be paralyzed by administration of muscle relaxants or injection of xylocaine. Draping should be done to include the entire face to the midline. This permits observation of facial muscular twitching. The neck should be prepped if neck dissection is contemplated.
Number
Benign Mixed Tumor Warthin's Tumor Lymphoma Adenocarcinoma Acinar Cell Carcinoma
15 3 2 1
If the tumor is benign and confined to the superficial lobe (80%), superficial lobectomy is an adequate procedure in most cases. However, if the tumor is located in the deep lobe (20%), total parotidectomy is performed. The facial nerve is preserved in all cases of benign tumor. For malignant low grade neoplasms, total parotidectomy, with preservation of facial nerve, is an ideal procedure. However, many authorities consider superficial parotidectomy adequate. HowTable 4. COMPARISON OF ST. FRANCIS GENERAL HOSPITAL S SERIES WITH OTHERS
Table 2. PRESENTING SYMPTOMS Total St. Francis S. Arena Series D. Hamilton Series
Total Mass Pain
Facial Paralysis
All All All
None
22 83 30
3 3 None
4 (all carcinoma) None
Incision. Adequate exposure is obtained by a "Y" or "S" shaped preauricular or cervical incision and anterior flaps are constructed to expose the entire surface of the parotid gland. The greater auricular nerve is identified and preserved and the facial nerve is identified by the truncal or peripheral method. In the truncal method, the parotid gland is dissected from the sternocleidomastoid muscle and the facial nerve is identified
St. Francis Hosp. Behar Series Gaisford Series H. H. Belding Series S. Arena Series
22 710 400 98 83
Benign % No.
Malignant % No.
20 548 295 72 68
2 162 105 26 15
90 70 74 73 78
9 23 26 27 22
ever, for malignant high grade neoplasms, total parotidectomy with enblock dissection of facial nerve is generally advocated in most cases. Enblock radical neck dissection is performed if cervical metastases are present. MATERIALS AND METHODS
The following is a clinical study of 22 patients treated for parotid neoplasms at St.
224
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
Francis General Hospital from 1969 to 1974. All charts were analyzed for age, sex, duration of symptoms, pathology, type of treatment and outcome. CLINICAL FEATURES
Age. The age incidence is given in Table 1.
MAY, 1976
Francis General Hospital generally agree with national experiences. However, no high grade parotid malignant tumors were treated at this hospital. This is probably incidental or reflects the referral patterns. Primary reconstruction of the facial nerve is advocated by most authorities. One patient with facial paralysis did not have primary facial nerve reconstruction.
Sex. Parotid neoplasms showed no predilection for sex in this study. Presenting Symptoms. The most common presenting symptom was a mass in front of or beneath the external ear. Pain was noted in only three patients (all benign). Facial nerve paralysis was not found preoperatively in any of our patients. The duration of symptoms varied from four weeks to five years (Table 2). Pathology. The tissue diagnosis of the 22 patients is shown in Tables 3, 4 and 5.
Seventy-five per cent of parotid neoplasms are benign. Sixty-five per cent of benign neoplasms are benign mixed tumors. Superficial parotidectomy for excision biopsy is advocated. The facial nerve should be sacrificed only when infiltrated by malignant neoplasms with immediate reconstruction, when possible.
Table 5. BENIGN MIXED TUMORS
1. ARENA, S. and J. A. STRAKA. Review of Parotid Tumors. Trans. Pa. Acad. Opthalmol.
COMPARED WITH OTHER SERIES
St. Francis Hosp. Behar Series Gaisford Series H. H. Belding Series S. Arena Series J. Garas
Total
No.
S
22 710 400
15 495 201 63 39 50
68 70 50 73 48 48
98
83 157
Seventy-five per cent of parotid neoplasms are benign while 25% are malignant. Sixtyfive percent of benign neoplasms are benign mixed tumors. TREATMENT
Benign Tumor. Twenty patients with benign parotid neoplasm had superficial parotidectomy. The facial nerve was sacrificed in one patient and reconstructed at the time of surgery. However, the facial nerve was sacrified in one patient without primary reconstructive procedures. Malignant Tumor. The facial nerve was sacrificed in one of the two patients with parotid gland carcinoma. COMMENT
The results of parotid surgery at St.
SUMMARY
LITERATURE CITED
Otolaryngol., 24:61-8, 1971. 2. BURKHARDT, B. R. Treatment of Parotid Tumor. Amer. Surg., 33:202-6, 1967. 3. BEAHRS, 0. H. Management of the Facial Nerve in Parotid Gland Surgery. Amer. J. Surg., 124:473-6, 1972. 4. BEAHRS, 0. H. Surgical Management of Parotid Lesion. Arch. Surg., 80:890-904, 1960. 5. BARDWILL, J. M. Tumors of the Parotid Gland, Review of Seven hundred-sixty Cases. Amer. J. Surg., 114:498-502, 1967. 6. BELDING, H. H. and D. E. PAGE. Parotid Tumors. Fifteen Year Review of 98 Cases. Amer. Surg., 32:735-8, Oct., 1966. 7. GAISFORD, J. C. Salivary Gland Tumors and Miscellaneous Associated Problems: Diagnosis, Pathology and Treatment. Plast. & Reconstruct. Surg., 19:458, 1957. 8. GAISFORD, J. C. Parotid Tumors. Plast. & Reconstruct. Surg., 43:504-10, 1969. 9. GAISFORD, J. C. Surgical Pathology and Its Relationship to the Management of Head and Neck Tumors. Plast. & Reconstruct. Surg., 36:185-90, 1965. 10. HANNA, D. C. Tumors of the Deep Lobe of the Parotid Gland. Amer. J. Surg., 116:524-7, 1968. 11. HANNA, D. C. Parotid Gland Tumor, Diagnosis and Treatment. Amer. J. Surg., 104:737-40, 1962. 12. LATHROP, F. K. Neoplasia of the Parotid Gland: Surgical Management. Minn. Med., 50:999-1002, 1967. 13. WARD, N. 0. Facial Paralysis: Before and After Parotid Surgery. Amer. Surg., 34:817-24, 1968.
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
MAY, 1976
Management of Parotid Neoplasms EARL BELLE SMITH, M.D., F. A. C.S., Director of Surgical Education & Research, St. Francis General Hospital, Pittsburgh, Pennsylvania
DAROTID neoplasms present
a
unique
management problem1-'3 in that the majority are benign. The recurrence rate can be high if management is not appropriate. Sacrifice of the facial nerve results in a deformity which demands adequate treatment and fear of facial nerve injury may lead to inadequate cancer surgery and a high recurrence rate. The objectives of this study are to review general principles of parotid gland surgery and make a comparative analysis of our experiences at St. Francis General Hospital with other series. ANATOMY
Although anatomical relationships of the facial nerve to the parotid gland are common knowledge, the following points should be emphasized: 1) the facial nerve leaves the skull through the stylomastoid foramen anterior to the mastoid process of the temporal bone and enters the parotid gland; 2) the facial nerve divides into temporofacial and cervicofacial trunks from which terminal branches arise; and 3) the parotid gland is arbitrarily divided into superficial and deep lobes by the facial nerve and its branches. PATHOLOGY
The following classification is generally accepted to outline the behavior of parotid neoplasms and their management. Seventy-five per cent of parotid neoplasms are benign and are classified as: 1) mixed tumor; 2) Warthin's tumor; 3) mucoepidermoid tumor; 4) oncocytoma; 5) benign lymphoma; and 6) papillary cystadenoma. Benign mixed tumor is the most common benign neoplasm. The mixed tumor and mucoepidermoid tumor show distinct tendencies
for recurrence following surgery. Twenty-five percent of all parotid neoplasms are malignant. The malignant parotid tumors are subdivided into low and high grade. Low grade neoplasms are characterized by a prolonged clinical course, progressive local growth and regional distant metastases. These neoplasms are as follows: 1) malignant mixed tumor; 2) mucoepidermoid carcinoma; 3) adenocystic carcinoma; and 4) acinar cell carcinoma. The adenocystic carcinoma invades the seventh nerve early and spreads along the course of lymphatics. High grade tumors are characterized by a short clinical course, rapid local infiltration, early regional and distant metastases. The squamous cell and undifferentiated varieties fall into this category. PREOPERATIVE EVALUATION
Clinical Diagnosis. The clinical diagnosis of parotid neoplasm is not always simple. It is often confused with cervical and facial lymph nodes and cysts. Generally, it is a firm, mobile and painless lump in front of the ear, below the ear lobe or just behind the angle of the mandible. Benign tumors are generally firm, slow growing, mobile and well-defined. Malignant tumors are hard in consistency with a rapid growth rate, fixity to adjacent structures and facial paralysis. Histological Diagnosis. The true nature of parotid neoplasm can be ascertained only by histological examination. The best biopsy technique is excisional biopsy. Needle biopsy has little place in diagnosis of parotid neoplasm. It often results in seeding of the tumor. In addition, the amount of tissue obtained is inadequate for pathological analysis.
Vol. 68, No. 3
Parotid Neoplasms TREATMENT
223
Various modalities of treatment are radiotherapy and surgery. Radiotherapy has not been established as definitive primary therapy. It is used as adjuvant therapy. Surgical treatment of parotid neoplasms is indicated because of their resistance to radiotherapy. The objectives of parotid gland tumor surgery are to completely remove the neoplasms and preserve the branches of the facial nerve.
as it passes in front of the facial vein and 1.5 cm lateral to mastoid process. In the peripheral method, the peripheral branches of the facial nerve are identified anterior to the parotid gland and traced to the trunk of the facial nerve. Dissection between parotid gland and facial nerve should be blunt and diathermy should not be used. Superficial lobectomy is performed by blunt dissection and frozen section is obtained.
Table 1. AGE INCIDENCE OF PATIENTS WITH
Table 3. TYPES OF PAROTID NEOPLASMS
PAROTID NEOPLASMS Type of Neoplasm Age
No. of Patients
Percentage
7 14 1
32 65 3
22
100
17-40 yr. 40-60 yr. Above 60 yr. Totals
Technique. Basically, the technique of parotid surgery is the same whether the tumor is benign or malignant. Wide excisional biopsy, i.e., superficial lobectomy, is recommended in all patients for tissue diagnosis. Endotracheal anesthesia is utilized exclusively and the facial nerve should not be paralyzed by administration of muscle relaxants or injection of xylocaine. Draping should be done to include the entire face to the midline. This permits observation of facial muscular twitching. The neck should be prepped if neck dissection is contemplated.
Number
Benign Mixed Tumor Warthin's Tumor Lymphoma Adenocarcinoma Acinar Cell Carcinoma
15 3 2 1
If the tumor is benign and confined to the superficial lobe (80%), superficial lobectomy is an adequate procedure in most cases. However, if the tumor is located in the deep lobe (20%), total parotidectomy is performed. The facial nerve is preserved in all cases of benign tumor. For malignant low grade neoplasms, total parotidectomy, with preservation of facial nerve, is an ideal procedure. However, many authorities consider superficial parotidectomy adequate. HowTable 4. COMPARISON OF ST. FRANCIS GENERAL HOSPITAL S SERIES WITH OTHERS
Table 2. PRESENTING SYMPTOMS Total St. Francis S. Arena Series D. Hamilton Series
Total Mass Pain
Facial Paralysis
All All All
None
22 83 30
3 3 None
4 (all carcinoma) None
Incision. Adequate exposure is obtained by a "Y" or "S" shaped preauricular or cervical incision and anterior flaps are constructed to expose the entire surface of the parotid gland. The greater auricular nerve is identified and preserved and the facial nerve is identified by the truncal or peripheral method. In the truncal method, the parotid gland is dissected from the sternocleidomastoid muscle and the facial nerve is identified
St. Francis Hosp. Behar Series Gaisford Series H. H. Belding Series S. Arena Series
22 710 400 98 83
Benign % No.
Malignant % No.
20 548 295 72 68
2 162 105 26 15
90 70 74 73 78
9 23 26 27 22
ever, for malignant high grade neoplasms, total parotidectomy with enblock dissection of facial nerve is generally advocated in most cases. Enblock radical neck dissection is performed if cervical metastases are present. MATERIALS AND METHODS
The following is a clinical study of 22 patients treated for parotid neoplasms at St.
224
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
Francis General Hospital from 1969 to 1974. All charts were analyzed for age, sex, duration of symptoms, pathology, type of treatment and outcome. CLINICAL FEATURES
Age. The age incidence is given in Table 1.
MAY, 1976
Francis General Hospital generally agree with national experiences. However, no high grade parotid malignant tumors were treated at this hospital. This is probably incidental or reflects the referral patterns. Primary reconstruction of the facial nerve is advocated by most authorities. One patient with facial paralysis did not have primary facial nerve reconstruction.
Sex. Parotid neoplasms showed no predilection for sex in this study. Presenting Symptoms. The most common presenting symptom was a mass in front of or beneath the external ear. Pain was noted in only three patients (all benign). Facial nerve paralysis was not found preoperatively in any of our patients. The duration of symptoms varied from four weeks to five years (Table 2). Pathology. The tissue diagnosis of the 22 patients is shown in Tables 3, 4 and 5.
Seventy-five per cent of parotid neoplasms are benign. Sixty-five per cent of benign neoplasms are benign mixed tumors. Superficial parotidectomy for excision biopsy is advocated. The facial nerve should be sacrificed only when infiltrated by malignant neoplasms with immediate reconstruction, when possible.
Table 5. BENIGN MIXED TUMORS
1. ARENA, S. and J. A. STRAKA. Review of Parotid Tumors. Trans. Pa. Acad. Opthalmol.
COMPARED WITH OTHER SERIES
St. Francis Hosp. Behar Series Gaisford Series H. H. Belding Series S. Arena Series J. Garas
Total
No.
S
22 710 400
15 495 201 63 39 50
68 70 50 73 48 48
98
83 157
Seventy-five per cent of parotid neoplasms are benign while 25% are malignant. Sixtyfive percent of benign neoplasms are benign mixed tumors. TREATMENT
Benign Tumor. Twenty patients with benign parotid neoplasm had superficial parotidectomy. The facial nerve was sacrificed in one patient and reconstructed at the time of surgery. However, the facial nerve was sacrified in one patient without primary reconstructive procedures. Malignant Tumor. The facial nerve was sacrificed in one of the two patients with parotid gland carcinoma. COMMENT
The results of parotid surgery at St.
SUMMARY
LITERATURE CITED
Otolaryngol., 24:61-8, 1971. 2. BURKHARDT, B. R. Treatment of Parotid Tumor. Amer. Surg., 33:202-6, 1967. 3. BEAHRS, 0. H. Management of the Facial Nerve in Parotid Gland Surgery. Amer. J. Surg., 124:473-6, 1972. 4. BEAHRS, 0. H. Surgical Management of Parotid Lesion. Arch. Surg., 80:890-904, 1960. 5. BARDWILL, J. M. Tumors of the Parotid Gland, Review of Seven hundred-sixty Cases. Amer. J. Surg., 114:498-502, 1967. 6. BELDING, H. H. and D. E. PAGE. Parotid Tumors. Fifteen Year Review of 98 Cases. Amer. Surg., 32:735-8, Oct., 1966. 7. GAISFORD, J. C. Salivary Gland Tumors and Miscellaneous Associated Problems: Diagnosis, Pathology and Treatment. Plast. & Reconstruct. Surg., 19:458, 1957. 8. GAISFORD, J. C. Parotid Tumors. Plast. & Reconstruct. Surg., 43:504-10, 1969. 9. GAISFORD, J. C. Surgical Pathology and Its Relationship to the Management of Head and Neck Tumors. Plast. & Reconstruct. Surg., 36:185-90, 1965. 10. HANNA, D. C. Tumors of the Deep Lobe of the Parotid Gland. Amer. J. Surg., 116:524-7, 1968. 11. HANNA, D. C. Parotid Gland Tumor, Diagnosis and Treatment. Amer. J. Surg., 104:737-40, 1962. 12. LATHROP, F. K. Neoplasia of the Parotid Gland: Surgical Management. Minn. Med., 50:999-1002, 1967. 13. WARD, N. 0. Facial Paralysis: Before and After Parotid Surgery. Amer. Surg., 34:817-24, 1968.
