Lymph node involvement by direct extension in adenoid cystic carcinoma. Absence of classic embolic lymph node metastasis

Incidence and spread pattern of lymph node metastasis from submandibular gland cancer

OBJECTIVES

To clarify the indication of neck dissection (ND) for patient with submandibular gland (SMG) cancer.

METHODS

A total of 43 patients with SMG cancer were retrospectively analyzed. Forty-one patients underwent ND: Levels I-V in 19 patients, Levels I-III in 18 patients, and Level Ib in 4 patients. The other two patients did not undergo ND, since preoperative diagnoses were benign. Postoperative radiotherapy was performed in 19 patients with positive surgical margin, high grade cancer or stage IV disease.

RESULTS

LN metastases were pathologically confirmed in all patients with cN + and 6 out of 31 patients with cN-. No patients developed regional recurrence during follow-up periods. Ultimately, LN metastases were pathologically confirmed in 17 of 27 high grade, one out of 9 intermediate grade, but not in 7 low grade.

CONCLUSIONS

Prophylactic neck dissection should be considered in T3/4 and high grade SMG cancers.

The Neuropilins and Their Ligands in Hematogenous Metastasis of Salivary Adenoid Cystic Carcinoma-An Immunohistochemical Study

PURPOSE

We investigated the expression of neuropilin-1 (NRP1), neuropilin-2 (NRP2), vascular endothelial growth factor-A (VEGF-A), semaphorin-3A (Sema-3A), and semaphorin-3F (Sema-3F) in normal salivary gland (NSG) tissue, nonmetastatic salivary adenoid cystic carcinoma (SACC), and metastatic SACC to better understand their role in intratumoral angiogenesis and hematogenous metastasis of SACC.

PATIENTS AND METHODS

The study included 60 SACC patients, equally divided between nonmetastatic SACC and metastatic SACC. We used 30 NSG samples as the control. The expression of cytokines was studied by immunohistochemistry and compared using the integrated optical density. The relationship between NRP1, NRP2, VEGF-A, and Sema-3A expression and microvessel density (MVD) was analyzed in the 3 groups.

RESULTS

In metastatic SACC, the expression levels of NRP1 and VEGF-A were significantly greater than those in nonmetastatic SACC and NSG. The expression of Sema-3A and Sema-3F was significantly lower in metastatic SACC than that in nonmetastatic SACC and NSG (P < .0001). No significant differences were found in NRP2 expression among the 3 groups (P = .43). The MVD of metastatic SACC was significantly greater than that of nonmetastatic SACC and NSG (P < .0001). However, the lymphatic vessel density of the 3 groups was not significantly different statistically. The relationship between MVD and NRP1 or VEGF-A showed a significant positive correlation (P < .0001, for both). However, a significant negative correlation was found between the MVD and Sema-3A or Sema-3F expression (P < .0001, for both).

CONCLUSIONS

Hematogenous metastasis of SACC is correlated with high expression of NRP1 and VEGF-A and low expression of Sema-3A and Sema-3F. The increased numbers of microvessels induced by VEGF-A signaling, combined with NRP1, could be one of the key reasons leading to the enhanced hematogenous metastasis in SACC.

Cervical lymph node metastasis in adenoid cystic carcinoma of the major salivary glands

Objective:

To verify the prevalence of cervical lymph node metastasis in adenoid cystic carcinoma of major salivary glands, and to establish recommendations for elective neck treatment.

Methods:

A search was conducted of the US National Library of Medicine database. Appropriate articles were selected from the abstracts, and the original publications were obtained to extract data.

Results:

Among 483 cases of major salivary gland adenoid cystic carcinoma, a total of 90 (18.6 per cent) had cervical metastasis. The prevalence of positive nodes from adenoid cystic carcinoma was 14.5 per cent for parotid gland, 22.5 per cent for submandibular gland and 24.7 per cent for sublingual gland. Cervical lymph node metastasis occurred more frequently in patients with primary tumour stage T3–4 adenoid cystic carcinoma, and was usually located in levels II and III in the neck.

Conclusion:

Adenoid cystic carcinoma of the major salivary glands is associated with a significant prevalence of cervical node metastasis, and elective neck treatment is indicated for T3 and T4 primary tumours, as well as tumours with other histological risk factors.

A rare case of lacrimal adenoid cystic carcinoma with large hepatic and multiple pulmonary metastases with successful surgical treatment

INTRODUCTION

Adenoid cystic carcinoma (ACC) of the lacrimal gland is rare but with high recurrence rates and late metastases. They occasionally metastasise via haematogenous spread to lungs, brain and bone. Liver is a rare site of metastasis and is usually present with disseminated disease.

PRESENTATION OF CASE

A 42 year old lady, a known case of adenoid cystic carcinoma of the lacrimal gland who had been operated 4 years ago for the same followed by chemotherapy and radiotherapy. She was detected with large hepatic and bilateral multiple pulmonary metastases. A right hepatectomy was done. After six months when her general condition improved we did a staged pulmonary metastatectomy. Histology confirmed the diagnosis. She is presently doing well with no recurrence since 18 months.

DISCUSSION

Usually asymptomatic, the commonest symptom is pain. It is a locally invasive disease with a poor prognosis if detected late. Surgery is the only proven therapy. Isolated hepatic metastases being managed surgically has been reported. However, extensive, staged, surgical resection of hepatic and pulmonary metastases has not been reported.

CONCLUSION

Lacrimal ACC is an aggressive tumour with known late metastases with the liver being affected seldomly. Our case highlights that even disseminated metastases to the liver and the lungs from lacrimal ACC can be managed surgically with a good outcome. To our knowledge, no such report with distant metastases to the liver and the lung along with their successful surgical management has been reported.

Adenoid cystic carcinoma of the minor salivary glands: a retrospective series of 29 cases and review of the literature

OBJECTIVE

Approximately 78% of minor salivary gland tumors are malignant, of which adenoid cystic carcinoma (ACC) represents 15% in our series. ACC is an uncommon tumor characterized by slow growth and a high potential for recurrence. This series of 29 consecutive patients examines clincopathologic features, management, and survival outcomes.

MATERIALS AND METHODS

This study is a retrospective chart review of 29 patients with ACC of the minor salivary glands in a period of 23 years (1989 and 2012).

RESULTS

The mean age was 61.2 years (16-89 years), with no gender predilection. The majority occurred in the palate/maxilla (66%) and initial presentation was stage IV. Mean follow-up was 42.6 months. Recurrence rate was 10% local, 14% distant over the observation period.

CONCLUSIONS

The palate/maxilla is the preferred location for occurrence, and initial presentation at stage IV is common. Postoperative radiation remains a common strategy to prevent local recurrence in lesions with adverse features.

Extradural Spinal Metastasis of Adenoid Cystic Carcinoma (ACC): A Case Report

Adenoid cystic carcinoma (ACC) is a rare malignant tumour of the major salivary glands. It accounts for 10-15% of all salivary gland tumours and 1% of all head and neck tumours. Surgical resection followed by radiation is the choice of treatment for ACC. However, late loco-regional recurrence and metastasis is often seen emphasizing the importance of long-term follow-up. We report an unusual case of extradural metastasis of ACC in the dorsal spine. The primary submandibular gland tumour was resected 11 y back. A recurrence had been detected two years prior to the occurrence of spinal metastasis. Surgical decompression was done which was followed by palliative radiotherapy. Patient is symptomatically better, ambulant and on regular follow-up.

Adenoid cystic carcinoma: An unusual presentation

The adenoid cystic carcinoma is a relatively rare epithelial tumor of the major and minor salivary glands, accounting for about 1% of all malignant tumor of the oral and maxillofacial regions. Peak incidence occurs between the 5^th and 6^th decades of life. The clinical and pathological findings typical of this tumor include slow growth, peri-neural invasion, multiple local recurrences and distant metastasis. Herein, we report a case of adenoid cystic carcinoma of oropharynx with unusual clinical presentation. The diagnosis of this case and importance of cytology in diagnosing such cases is discussed.

Adenoid cystic carcinoma of palate: A case report and review of literature

Adenoid cystic carcinoma is an uncommon, slow growing malignant salivary gland tumor that is characterized by wide local infiltration, perineural spread, propensity to local recurrence and distant metastasis. In this paper, the authors present a case of adenoid cystic carcinoma affecting the palate and involving the maxillary sinus in a 60-year-old male patient along with a brief review of literature.

Adenoid cystic carcinoma - Clinical presentation and cytological diagnosis

Adenoid cystic carcinoma is a tumor arising from the minor salivary glands, the palate being the commonest site. It accounts for about 1% of all head and neck malignancies. We report a case with the typical presentation of a palatal growth with extensive intra-cranial invasion. The diagnosis of this case and a brief review of literature is discussed. Final diagnosis of this case was made from cytological reports. The dry smears stained with MGG were found to be definitely superior to the alcohol fixed slides stained with papanicolaou. The aim here is to highlight the importance of cytology in the diagnosis of such tumors.

Salivary gland adenoid cystic carcinoma with cervical lymph node metastasis: a preliminary study of 62 cases

Adenoid cystic carcinoma (ACC) is an infrequent malignant neoplasm that originates most commonly in the major and minor salivary glands of the head and neck region. This study provides new information on head and neck ACC with cervical lymph node metastasis. Of 616 patients who underwent primary tumour resection from 1995 to 2008 in the authors' hospital, 62 cases with cervical lymph node metastasis were analyzed. The general incidence of cervical lymph node metastasis in ACC was approximately 10%. The base of tongue, mobile tongue and mouth floor were the most frequent sites of lymph nodes metastasis, with incidences of 19.2%, 17.6% and 15.3%, respectively. Most cases occurred via a classic 'tunnel-style' metastasis and the level Ib and II regions were the most frequently involved. Primary site and lymphovascular invasion were significantly associated with lymph node metastasis. High patient mortality was significantly correlated with lymph node positive cases. The tongue-mouth floor complex has a high propensity for cervical lymph node metastasis, which occurs through a classic 'tunnel-style' metastasis. Peritumoral lymphovascular invasion could be taken as strong predictor for lymph node metastasis, which ultimately leads to poor prognosis of ACC patient. Selective neck dissection should be considered in such cases.

Management of adenoid cystic carcinoma of the breast: a Rare Cancer Network study

BACKGROUND

Mammary adenoid cystic carcinoma (ACC) is a rare breast cancer. The aim of this retrospective study was to assess prognostic factors and patterns of failure, as well as the role of radiation therapy (RT), in ACC.

METHODS

Between January 1980 and December 2007, 61 women with breast ACC were treated at participating centers of the Rare Cancer Network. Surgery consisted of lumpectomy in 41 patients and mastectomy in 20 patients. There were 51(84%) stage pN0 and 10 stage cN0 (16%) patients. Postoperative RT was administered to 40 patients (35 after lumpectomy, 5 after mastectomy).

RESULTS

With a median follow-up of 79 months (range, 6-285), 5-year overall and disease-free survival rates were 94% (95% confidence interval [CI], 88%-100%) and 82% (95% CI, 71%-93%), respectively. The 5-year locoregional control (LRC) rate was 95% (95% CI, 89%-100%). Axillary lymph node dissection or sentinel node biopsy was performed in 84% of cases. All patients had stage pN0 disease. In univariate analysis, survival was not influenced by the type of surgery or the use of postoperative RT. The 5-year LRC rate was 100% in the mastectomy group versus 93% (95% CI, 83%-100%) in the breast-conserving surgery group, respectively (p = 0.16). For the breast-conserving surgery group, the use of RT significantly correlated with LRC (p = 0.03); the 5-year LRC rates were 95% (95% CI, 86%-100%) for the RT group versus 83% (95% CI, 54%-100%) for the group receiving no RT. No local failures occurred in patients with positive margins, all of whom received postoperative RT.

CONCLUSION

Breast-conserving surgery is the treatment of choice for patients with ACC breast cancer. Axillary lymph node dissection or sentinel node biopsy might not be recommended. Postoperative RT should be proposed in the case of breast-conserving surgery.

Simultaneous pleomorphic adenoma of the left parotid gland and adenoid cystic carcinoma of the contralateral sublingual salivary gland: a case report

INTRODUCTION

Sublingual salivary gland neoplasms are extremely rare, accounting for only 0.3-1% of all epithelial salivary gland tumors. Most of the sublingual tumors are malignant, adenoid cystic carcinoma (ACC) and mucoepidermoid carcinoma (MEC) being the most common histological types. The coexistence of two salivary gland tumors located in different major salivary glands is uncommon.

CASE REPORT

A rare case of two simultaneous tumors of the major salivary glands, one in the sublingual and the other in the contralateral parotid gland in a female patient is reported.

DISCUSSION

The diagnostic procedure followed, and the management of the patient, is outlined in the paper.

Chemokine receptors in head and neck cancer: association with metastatic spread and regulation during chemotherapy

Head and neck carcinomas are histologically and clinically heterogeneous. While squamous cell carcinomas (SCC) are characterized by lymphogenous spread, adenoid cystic carcinomas (ACC) disseminate preferentially hematogenously. To study cellular and molecular mechanisms of organ-specific metastasis, we used SCC and ACC cell lines and tumor tissues, obtained from patients with primary or metastatic disease. Comprehensive analysis at the mRNA and protein level of human chemokine receptors showed that SCC and ACC cells exhibited distinct and nonrandom expression profiles for these receptors. SCC predominantly expressed receptors for chemokines homeostatically expressed in lymph nodes, including CC chemokine receptor (CCR) 7 and CXC chemokine receptor (CXCR)5. No difference in expression of chemokine receptors was seen in primary SCC and corresponding lymph node metastases. In contrast to SCC, ACC cells primarily expressed CXCR4. In chemotaxis assays, ACC cells were responsive to CXCL12, the ligand for CXCR4. Exposure of ACC cells to cisplatin resulted in upregulation of CXCR4 on the cell surface, which was repressed by the transcriptional inhibitor, alpha-amanitin. Treatment of ACC cells with CXCL12 resulted in the activation of Akt and ERK1/2 pathways. Furthermore, CXCL12 suppressed the rate of apoptosis induced by cisplatin in ACC cells, suggesting that signaling via CXCR4 may be part of a tumor cell survival program. Discrimination of the chemokine receptor profile in SCC and ACC in vitro and in tissues provided insights into their distinct biologic and clinical characteristics as well as indications that chemokine receptors might serve as future therapeutic targets in these malignancies.

Distant metastases of adenoid cystic carcinoma of the salivary glands and the value of diagnostic examinations during follow-up

BACKGROUND

Adenoid cystic carcinoma (ACC) accounts for approximately 10% of all neoplasms of the salivary glands. Late distant metastases and local recurrences are responsible for a rather low long-term survival rate.

AIM

To study the metastasizing pattern of ACC of the salivary glands in 51 patients.

METHOD

Fifty-one patients with an ACC in the intraoral/sublingual salivary glands (n = 30), parotid gland (n = 8), submandibular gland (n = 2), maxillary sinus (n = 6), and nasal cavity (n = 5) have been studied. The male-female ratio was 1:1, the mean age was 54.3 (range, 19-81) years. In 30 cases treatment consisted of surgery and radiotherapy. In 13 cases surgery alone was carried out. The average follow-up time was 117.8 (range, 1-171) months.

RESULTS

In 28 cases (54.9%) distant metastases occurred, and in 3 patients (5.8%) regional lymph node metastases occurred. In 12 of the 28 patients with distant metastases (42.8%), only the lungs were involved, whereas in 5 of the 28 patients (17.8%), the distant metastases occurred in other organs (eg, bones and brain). In 11 of the 28 patients (39.2%) metastases were found both in the lungs and other organs. Twenty-four of the 51 patients (47.0%) died because of their tumor. The average time between the occurrence of lung metastases and death was 32.3 months and between the occurrence of metastases elsewhere and death 20.6 months.

CONCLUSION

Distant metastases of ACC of the salivary glands occur most often in the lungs. Although these lung metastases are the first to occur, these patients die later than patients with distant metastases in other organs. The value of annual chest films or other tests for the presence of distant metastases during follow-up after surgical removal of an ACC seems rather questionable.

Adenoid cystic carcinoma of the maxillary antrum

PURPOSE

To investigate characteristic clinical features and outcome for patients with adenoid cystic carcinoma (ACC) of the maxillary antrum.

PATIENTS AND METHODS

Twenty-two patients with ACC of the maxillary antrum were initially treated with surgery alone (3 patients), radiation alone (9 patients), or a combination of surgery and radiation (10 patients). Salvage treatment for initial failure was individualized. Patterns of failure, survival, and prognostic factors were retrospectively analyzed.

RESULTS

The most frequent site of failure was local recurrence at the primary site (72.7%). All patients treated with either surgery alone or radiation alone experienced one or more local recurrences, whereas patients who received planned combined surgery and radiation had a much lower local recurrence rate (40%). Neck node failure (4.6%) was an uncommon event, whereas distant metastases were clinically documented in seven patients (32%). Most of the treatment failures appeared within 5 years, but treatment failures after 5 years were not uncommon. The overall survival and disease-free survival rates at 10 years were 37.6% and 13.6%, respectively. Clinicopathological factors, such as location of primary tumor, tumor stage, and histological grade were of no value in predicting a favorable survival. The significant prognostic factors influencing 10-year survival were the pathological finding of perineural invasion and the initial mode of treatment.

CONCLUSION

ACC of the maxillary antrum represented a unique natural history characterized by a more aggressive tumor behavior and an unfavorable prognosis. Combined surgery and radiotherapy is recommended for optimal local control and survival.

Metastatic Adenoid Cystic Carcinoma of Salivary Glands: Case Reports and Review of the Literature

BACKGROUND: Adenoid cystic carcinoma is an uncommon tumor of the salivary gland. Little has been published on the chemotherapy of this neoplasm. METHODS: The literature on this disease is reviewed, and data from seven unpublished cases are presented. RESULTS: Four patients received cyclophosphamide. One responded, and another had pain relief. The literature review did not identify any single drug or combination that might be regarded as the treatment of choice. CONCLUSIONS: Systematic, multi-institutional studies are required to determine appropriate systemic treatment for metastatic adenoid cystic carcinoma of salivary gland origin.

Adenoid cystic carcinoma of the sublingual gland--an unusual presentation

A case of adenoid cystic carcinoma of the sublingual salivary gland presenting as recurrent submandibular salivary gland swelling is described. The obstructive symptoms were due to involvement of the ipsilateral submandibular duct by the tumour. A review of the literature suggests that this is the first such case to be reported. The importance of intra-oral examination when investigating swellings of the neck is emphasised.

Prognostic factors for adenoid cystic carcinoma of the head and neck: a retrospective evaluation of 96 cases

Cases of adenoid cystic carcinomas of the salivary (n = 90) and lacrimal glands (n = 6) from the years 1965-1980 were evaluated retrospectively with regard to clinical, epidemiologic and histomorphologic parameters, and in 52 cases, nuclear DNA content was assessed using a single cell scanning cytophotometry procedure in order to determine prognostic factors. Clinical courses were poor with a high incidence of recurrences, hematogenous metastases and deaths from tumor. Histology was related to prognosis, glandular tumors showing a better prognosis than solid ones. Tumor size greater than 4 cm was correlated with an unfavorable clinical course in all cases. Cytophotometry yielded various types of histograms (7 diploid, 10 proliferative, 14 triploid, 19 atypical, 2 tetraploid). Significant correlations were found as to the time of survival, tumors with diploid histograms showing the longest intervals and those with atypical ones the shortest. Although the prognosis of adenoid cystic carcinoma remains poor, cytophotometry can offer additional prognostic information in the individual case.

Adenoid cystic carcinoma of the salivary glands: clinicopathological survey of 51 patients

A clinicopathological study of 51 cases of adenoid cystic carcinoma in the head and neck region seen over a period of 20 years is presented. The correlation between various histological features and their impact on the results is attempted. Longterm results with respect to loco-regional recurrences, distant metastases and survival with various modalities of therapy are presented. Although this is a small series, radical surgery in keeping with the aim of avoiding undue mutilation, thus preserving the quality of life, followed by a full course of radiotherapy has been the mainstay of treatment and the results here presented justify this approach.

The adenoid cystic carcinoma. Special aspects of its growth and therapy

In spite of its rare incidence the adenoid cystic carcinoma must be treated with respect because of its hidden malignant character. In 5 out of 21 patients recurrences occurred much longer than 5 years after the first operation. The extension of this tumour along branches of the trigeminal nerve could be well demonstrated in 7 of our patients where we were able to produce histological proof or radiographic evidence. The theory of tumour growth along the "tissue of least resistance" is illustrated by a special case report. As for the therapy, ultra-radical surgery has proved to be the most effective so far, whereas radio- or chemotherapy were only useful as palliative measures.

Adenoid cystic carcinoma presenting as a mass in the neck

Three of a personal series of 82 patients with adenoid cystic carcinoma presented with a node in the neck. Two of these patients had no discoverable primary tumour. One of the latter died rapidly, and might have had an undisclosed primary tumour in the lung. The other remains well 3 years after radical neck dissection, and it is possible that he had a tumour arising in an aberrant cervical salivary rest.

Adenoid cystic carcinoma of the major and minor salivary glands. A clinicopathological study of 17 cases

Local recurrence and distant metastasis were studied in relation to treatment modality and histological findings in 17 patients with adenoid cystic carcinoma of the major and minor salivary glands. Fifteen patients underwent surgical resection with or without postoperative irradiation and the others were treated by irradiation alone. Local recurrence developed in nine patients (52.9%), mostly within two years of the treatment. Incomplete removal was the major reason for the failure to control the primary lesion. Postoperative irradiation was of value in preventing recurrence in patients who demonstrated microscopic residual disease at the surgical margins, whereas it was not effective if gross residual tumour was recognized. Direct surgical intervention on the tumour tissue could have been the possible cause for the distant metastasis that developed in 10 (58.8%) of the 17 patients. Surgical excision with a wider safety margin than the visibly affected area, followed by postoperative irradiation and chemotherapy was essential to obtain a better prognosis.

Lymph node metastases in adenoid cystic carcinoma

The clinical characteristics of 76 patients with adenoid cystic carcinoma seen during a 22-year period are described. Lymph node metastases at presentation or later occurred almost exclusively in men, and the five-year rate of "node-free" survival was 62 per cent for men and 95 per cent for women. Node metastases were more common in poorly differentiated tumors, but site and stage of the primary disease did not affect the metastatic rate. Surgery scarcely improved the rate of survival of patients with nodal metastases. The authors were unable to confirm previous observations that embolic nodal metastases at a distance from the primary tumor do not occur.

Intracranial perineural metastasis of adenoid cystic carcinoma of head and neck

Three cases of intracranial perineural metastasis from adenoid cystic carcinoma of the head and neck are presented. The metastases presented more than 1 year (14 months to 5.5 years) after the primary tumor had been successfully treated without any evidence of local recurrence. Computed tomography of the intracranial metastasis demonstrated well-demarcated, hyperdense, enhancing extraaxial masses indistinguishable from meningioma. An intracranial extraaxial mass lesion with the appearance of a meningioma in a patient with known adenoid cystic carcinoma of the head and neck, regardless of the presence or absence of local recurrence, should be considered as metastasis until proved otherwise.

Reflections on the management of adenoid cystic carcinoma of the nasal cavity and paranasal sinuses

Adenoid cystic carcinoma of the nasal cavity and paranasal sinuses has a unique natural history. It has a propensity for frequent local recurrence and early perineural and hematogenous spread. These factors, together with a complex anatomic situation, make adequate oncologic surgery extremely difficult. The incidence of local recurrence is lower in those patients receiving more radical primary surgery, but the choice between conservative and radical management may not alter prognosis. Indeed, it is doubtful if any patients are cured of this disease.

Lymph node metastases in adenoid cystic carcinoma of the submaxillary gland

The incidence of neck metastases in adenoid cystic carcinoma of the head and neck is considered low and reported incidence range from 0 to 18%. If tumors of the submaxillary gland are considered separately, the incidence of neck metastases reported ranges from 0 to 100%, with a pooled incidence of 34%, significantly higher (P less than 0.001) than that reported for the parotid gland, which ranges from 0 to 21% with a pooled incidence of 10%. It may be suggested that the high incidence of neck metastases in adenoid cystic carcinoma of the submaxillary gland is due, in some cases, to direct extention of the tumor from the gland to the adjacent nodes or from infiltrated surrounding soft tissues rather than by a classic embolic metastasis. In our series of 10 cases, 4 cases showed lymph node metastases. In 3 of these, slides of the radical neck dissection were available for review and showed direct extension of the tumor from surrounding involved soft tissues, although the possibility of embolic metastasis could not be excluded. In the 3 patients with neck metastases at the time of initial diagnosis, distant metastases also developed early in the course of the disease.

Adenoid cystic carcinoma: biologic behavior in 38 patients

This study presents the clinical and pathologic data on 38 patients with adenoid cystic carcinoma. Most of the tumors arose from the major salivary glands or the mucus glands of the upper respiratory tract and oral cavity. The typical biological behavior of these tumors was slow but aggressive local growth despite all therapy, followed by eventual death from local disease and/or metastases. Twenty-eight of the patients have died, 22 from adenoic cystic carcinoma, 3 from postoperative complications, and 3 from intercurrent disease. Of the 10 living patients, 4 have active disease, 2 have no evidence of disease 14 years after diagnosis, and 4 have no evidence of disease but follow-up is less than 5 years. We compared various microscopic features of the tumors, including histologic grading, with prognosis but did not demonstrate a correlation in this small series.

The pathology of head and neck tumors: salivary glands, part 4

Adenoid cystic carcinomas and adenocarcinomas of salivary tissues are more plentiful in minor than in major salivary glands. In the latter, they comprise no more than 10% of tumors. In both sites, however, their clinical course is characterized by local aggressiveness, recurrences, and a relatively torpid and protracted course, eventually leading to death. The clinicopathologic aspects of these two lesions form the major part of this report. Their behavior is contrasted with that of the two other lesions presented: heterotopic salivary tissue, which is seldom the site of neoplasia; and necrotizing sialometaplasia, a self-limited disorder that simulates malignancy both clinically and histopathologically.