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Biomedical subjects

William M Mendenhall

Publications and source records attributed to William M Mendenhall.

At least 19 recordsLinked to original sources
PubMed2007

Do pre-irradiation dental extractions reduce the risk of osteoradionecrosis of the mandible?

BACKGROUND: This study was done to determine if pre-radiotherapy (pre-RT) dental extractions reduce the risk of osteoradionecrosis (ORN). METHODS: Between 1987 and 2004, 413 patients with oropharyngeal carcinomas were treated with definitive RT at the University of Florida. Dentate patients underwent pretreatment dental evaluation. Teeth in the RT field were usually extracted if thought to have poor long-term prognosis from dental disease. The endpoint was > or = grade 2 ORN using a modified staging system. Patients were excluded for local recurrence, additional RT above the clavicles, or head and neck surgery besides neck dissection. RESULTS: ORN rates were as follows: edentulous, <1%; teeth in-field with pre-RT extractions, 15%; and teeth in-field without pre-RT extractions, 9%. Patients with poor in-field teeth and pre-RT extractions had a higher 5-year incidence of ORN than those who did not have pre-RT extractions (16% vs 6%, p = .48). Likewise, for those with in-field teeth in good condition and pre-RT extractions, the 5-year ORN incidence was higher than for those who did not undergo extractions (15% vs 2%, p = .42). Multivariate analysis revealed increased ORN risk with doses of >70 Gy, once-daily fractionation, or brachytherapy. CONCLUSION: Pre-RT extractions do not appear to reduce the risk of ORN.

Adult↗
PubMed2006

Definitive radiotherapy for head-and-neck cancer with radiographically positive retropharyngeal nodes: incomplete radiographic response does not necessarily indicate failure.

PURPOSE: Our aim was to report the control rate of radiographically positive retropharyngeal (RP) nodes with radiation therapy (RT) and to correlate posttreatment imaging with clinical outcome. METHODS AND MATERIALS: Sixteen patients treated with definitive RT for head-and-neck cancer had radiographically positive RP nodes (size >1 cm in largest axial dimension, or presence of focal enhancement, lucency, or calcification), and both pre-RT and post-RT image sets available for review. An additional 21 patients with unconfirmed radiographically positive RP nodes had post-RT imaging, which consisted of computed tomography (CT) at a median of 4 weeks after completing RT. Patients with positive post-RT RP nodes underwent observation with serial imaging. RESULTS: Of 16 patients with pre-RT and post-RT images available for review, 9 (56%) had a radiographic complete response, and of 21 patients with unconfirmed positive RP nodes with post-RT images available for review, 14 (67%) had a radiographic complete response. In all, 14 patients with incomplete response on post-RT imaging experienced control of their disease with no further therapy, and no RP node or neck failures were noted during a median follow-up of 2.8 years. Six patients with positive post-RT RP nodes had serial imaging available for review, and none demonstrated radiographic progression of disease. CONCLUSIONS: Radiographic response at 4 weeks may not accurately reflect long-term locoregional control, as RP nodes may continue to resolve over time. The highest index of suspicion should be reserved for patients with progressive changes in size, focal lucency, or focal enhancement on serial imaging after RT.

Adult↗
PubMed2006

Radiotherapy after subtotally resected or recurrent ganglioglioma.

PURPOSE: Gangliogliomas can recur after subtotal resection (STR). The role of postoperative radiation therapy (RT) is undefined. METHODS AND MATERIALS: Eight consecutive patients with low-grade gangliogliomas (n = 7) or anaplastic gangliogliomas (n = 1) were treated with RT between 1987 and 2004. Median age was 17 years. Five patients received adjuvant RT after STR at a median time of 6 weeks after surgery. Three patients received salvage RT at a median time of 17 months after surgery. The median dose of RT was 54 Gy. Control was defined as no progressive disease on serial imaging. Median follow-up was 8.8 years. RESULTS: Of the 7 patients with low-grade gangliogliomas, 3 were controlled after RT and 4 recurred locally. Recurrences were controlled with further surgery (n = 2), chemotherapy (n = 1), or re-irradiation (n = 1) (median follow-up, 9 years after salvage therapy). Patients who received adjuvant RT after STR of their low-grade gangliogliomas had an overall local control rate of 75%. All 3 patients who were treated with salvage RT had recurrences in the treated area alone (n = 2) or in the treated area with leptomeningeal spread (n = 1). The patient with an anaplastic ganglioglioma was treated with adjuvant RT, and had recurrence in the radiation field after 4 months, then died 1 month later. CONCLUSIONS: Adjuvant RT may be indicated to treat select patients with subtotally resected gangliogliomas. Salvage RT for recurrence is probably less effective for long-term control; however, patients who recur may still be candidates for effective salvage therapies in the absence of malignant transformation.

Adolescent↗
PubMed2006

Adjuvant radiotherapy for cutaneous melanoma: comparing hypofractionation to conventional fractionation.

PURPOSE: To examine locoregional control after adjuvant radiotherapy (RT) for cutaneous melanoma and compare outcomes between conventional fractionation and hypofractionation. METHODS AND MATERIALS: Between January 1980 and June 2004, 56 patients with high-risk disease were treated with adjuvant RT. Indications for RT included: recurrent disease, cervical lymph node involvement, lymph nodes >3 cm, more than three lymph nodes involved, extracapsular extension, gross residual disease, close or positive margins, or satellitosis. Hypofractionation was used in 41 patients (73%) and conventional fractionation was used in 15 patients (27%). RESULTS: The median age was 61 years (21->90). The median follow-up among living patients was 4.4 years (range, 0.6-14.4 years). The primary site was located in the head and neck in 49 patients (87%) and below the clavicles in 7 patients (13%). There were 7 in-field locoregional failures (12%), 3 out-of-field regional failures (5%), and 24 (43%) distant failures. The 5-year in-field locoregional control (ifLRC) and freedom from distant metastases (FFDM) rates were 87% and 43%, respectively. The 5-year cause-specific (CSS) and overall survival (OS) was 57% and 46%, respectively. The only factor associated with ifLRC was satellitosis (p = 0.0002). Nodal involvement was the only factor associated with FFDM (p = 0.0007), CSS (p = 0.0065), and OS (p = 0.016). Two patients (4%) who experienced severe late complications, osteoradionecrosis of the temporal bone and radiation plexopathy, and both received hypofractionation (5%). CONCLUSIONS: Although surgery and adjuvant RT provides excellent locoregional control, distant metastases remain the major cause of mortality. Hypofractionation and conventional fractionation are equally efficacious.

Adult↗
PubMed2006

American Society of Clinical Oncology clinical practice guideline for the use of larynx-preservation strategies in the treatment of laryngeal cancer.

PURPOSE: To develop a clinical practice guideline for treatment of laryngeal cancer with the intent of preserving the larynx (either the organ itself or its function). This guideline is intended for use by oncologists in the care of patients outside of clinical trials. METHODS: A multidisciplinary Expert Panel determined the clinical management questions to be addressed and reviewed the literature available through November 2005, with emphasis given to randomized controlled trials of site-specific disease. Survival, rate of larynx preservation, and toxicities were the principal outcomes assessed. The guideline underwent internal review and approval by the Panel, as well as external review by additional experts, members of the American Society of Clinical Oncology (ASCO) Health Services Committee, and the ASCO Board of Directors. RESULTS: Evidence supports the use of larynx-preservation approaches for appropriately selected patients without a compromise in survival; however, no larynx-preservation approach offers a survival advantage compared with total laryngectomy and adjuvant therapy with rehabilitation as indicated. RECOMMENDATIONS: All patients with T1 or T2 laryngeal cancer, with rare exception, should be treated initially with intent to preserve the larynx. For most patients with T3 or T4 disease without tumor invasion through cartilage into soft tissues, a larynx-preservation approach is an appropriate, standard treatment option, and concurrent chemoradiotherapy therapy is the most widely applicable approach. To ensure an optimum outcome, special expertise and a multidisciplinary team are necessary, and the team should fully discuss with the patient the advantages and disadvantages of larynx-preservation options compared with treatments that include total laryngectomy.

Clinical Trials, Phase III as Topic↗
PubMed2006

Intensity-modulated radiotherapy in the standard management of head and neck cancer: promises and pitfalls.

The purpose of this article is to review the role of intensity-modulated radiotherapy (IMRT) in the standard management of patients with head and neck cancer through a critical review of the pertinent literature. IMRT may result in a dose distribution that is more conformal than that achieved with three-dimensional conformal radiotherapy (3D CRT), allowing dose reduction to normal structures and thus decreasing toxicity and possibly enhancing locoregional control through dose escalation. Disadvantages associated with IMRT include increased risk of a marginal miss, decreased dose homogeneity, increased total body dose, and increased labor and expense. Outcomes data after IMRT are limited, and follow-up is relatively short. Locoregional control rates appear to be comparable to those achieved with 3D CRT and, depending on the location and extent of the tumor, late toxicity may be lower. Despite limited data on clinical outcomes, IMRT has been widely adopted as a standard technique in routine practice and clinical trials. The use of IMRT involves a learning curve for the practitioner and will continue to evolve, requiring continuing education and monitoring of outcomes from routine practice. Additional standards pertaining to a variety of issues, including target definitions and dose specification, need to be developed. Phase III trials will better define the role of IMRT in coming years.

Antineoplastic Agents↗
PubMed2006

Postradiotherapy neck dissection for lymph node-positive head and neck cancer: the use of computed tomography to manage the neck.

PURPOSE: To determine how to use node response on computed tomography (CT) to indicate the need for neck dissection. PATIENTS AND METHODS: Five hundred fifty patients with lymph node-positive head and neck cancer were treated between 1990 and 2002 with radiotherapy (RT) at a median dose of 74.4 Gy; 24% of these patients (n = 133) were treated with chemotherapy. Three hundred forty-one patients (62%) underwent planned post-RT neck dissection. Physical examination and contrast-enhanced CT were performed 30 days after completion of RT. CT images were reviewed in 211 patients for lymph node size (largest axial dimension) and presence of a focal abnormality (lucency, enhancement, or calcification). By correlating post-RT CT to neck dissection pathology, criteria associated with a low likelihood of residual disease were identified. A subset of patients who fit these criteria of radiographic response who did not undergo post-RT neck dissection was observed for recurrence. RESULTS: Radiographic complete response (rCR) was defined as the absence of any large (> 1.5 cm) or focally abnormal lymph node. Correlation of response with neck dissection pathology indicated a negative predictive value of 77% for complete clinical response and 94% for rCR. In 32 patients (median follow-up time, 3.2 years) with rCR who did not undergo post-RT neck dissection, the 5-year ultimate neck control rate (100%) and cause-specific survival rate (72%) were not significantly different from the rates of patients with a negative post-RT neck dissection. CONCLUSION: Patients with rCR 4 weeks after RT can be spared from a post-RT neck dissection regardless of initial node stage.

Adult↗
PubMed2006

Low-dose prophylactic craniospinal radiotherapy for intracranial germinoma.

PURPOSE: To report outcomes of patients with localized intracranial germinoma treated with low-dose craniospinal irradiation (CSI) followed by a boost to the ventricular system and primary site. METHODS AND MATERIALS: Thirty-one patients had pathologically confirmed intracranial germinoma and no spine metastases. Low-dose CSI was administered in 29 patients: usually 21 Gy of CSI, 9.0 Gy of ventricular boost, and a 19.5-Gy tumor boost, all at 1.5 Gy per fraction. Our neuroradiologist recorded three-dimensional tumor size on magnetic resonance images before, during, and after radiotherapy. RESULTS: With a median follow-up of 7.0 years, 29 of 31 patients (94%) are disease free. One failure had nongerminomatous histology; the initial diagnosis was a sampling error. Of 3 patients who did not receive CSI, 1 died. No patient developed myelopathy, visual deficits, dementia, or skeletal growth problems. In locally controlled patients, tumor response according to magnetic resonance scan was nearly complete within 6 months after radiotherapy. CONCLUSIONS: Radiotherapy alone with low-dose prophylactic CSI cures almost all patients with localized intracranial germinoma. Complications are rare when the daily dose of radiotherapy is limited to 1.5 Gy and the total CSI dose to 21 Gy. Patients without a near-complete response to radiotherapy should undergo resection to rule out a nongerminomatous element.

Adolescent↗
PubMed2006

Implications for clinical staging of metastatic cutaneous squamous carcinoma of the head and neck based on a multicenter study of treatment outcomes.

BACKGROUND: Cutaneous squamous cell carcinoma (SCC) of the head and neck is a common cancer that has the potential to metastasize to lymph nodes in the parotid gland and neck. Previous studies have highlighted limitations with the current TNM staging system for metastatic skin carcinoma. The aim of this study was to test a new staging system that may provide better discrimination between patient groups. METHODS: A retrospective multicenter study was conducted on 322 patients from three Australian and three North American institutions. All had metastatic cutaneous SCC involving the parotid gland and/or neck and all were treated for cure with a minimum followup time of 2 years. These patients were restaged using a newly proposed system that separated parotid disease (P stage) from neck disease (N stage) and included subgroups of P and N stage. Metastases involved the parotid in 260 patients (149 P1; 78 P2; 33 P3) and 43 of these had clinical neck disease also (22 N1; 21 N2). Neck metastases alone occurred in 62 patients (26 N1; 36 N2). Ninety percent of patients were treated surgically and 267 of 322 received radiotherapy. RESULTS: Neck nodes were pathologically involved in 32% of patients with parotid metastases. Disease recurred in 105 (33%) of the 322 patients, involving the parotid in 42, neck in 33, and distant sites in 30. Parotid recurrence did not vary significantly with P stage. Disease-specific survival was 74% at 5 years. Survival was significantly worse for patients with advanced P stage: 69% survival at 5 years compared with 82% for those with early P stage (P = 0.02) and for those with both parotid and neck node involvement pathologically: 61% survival compared with 79% for those with parotid disease alone (P = 0.027). Both univariate and multivariate analysis confirmed these findings. Clinical neck involvement among patients with parotid metastases did not significantly worsen survival (P = 0.1). CONCLUSIONS: This study, which included a mixed cohort of patients from six different institutions, provides further information about the clinical behavior of metastatic cutaneous SCC of the head and neck. The hypothesis that separation of parotid and neck disease in a new staging system is supported by the results. The benefit of having subgroups of P and N stage is uncertain, but it is likely to identify patients with unfavorable characteristics that may benefit from further research.

Carcinoma, Squamous Cell↗
PubMed2006

Definitive radiotherapy for squamous cell carcinoma of the base of tongue.

OBJECTIVE: To evaluate definitive radiotherapy (RT) for treatment of base of tongue cancer. METHODS: There were 333 patients with squamous cell carcinoma of the base of tongue treated with definitive RT and had follow-up from 0.2 to 26.2 years. Follow-up on living patients ranged from 1.2 to 26.2 years (median, 6.6 years). RESULTS: Local control rates at 5 years were: T1, 98%; T2, 92%; T3, 82%; and T4, 53%. The 5-year rates of local-regional control rates were: I-II, 100%; III, 82%; IVA, 87%; and IVB, 58%. The rates of absolute and cause-specific survival at 5 years were as follows: I-II, 67% and 91%; III, 66% and 77%; IVA, 67% and 84%; and IVB, 33% and 45%. Severe complications developed in 52 patients (16%). CONCLUSION: Our data and review of the pertinent literature reveal that the local-regional control rates and survival rates after RT were comparable to those after surgery, and the morbidity associated with RT was less.

Adult↗
PubMed2006

Sinonasal undifferentiated carcinoma.

PURPOSE: The purpose of this paper is to discuss the treatment and outcomes for patients with sinonasal undifferentiated carcinoma. METHODS: Review of the pertinent literature. RESULTS: Most series contain a limited number of patients treated with various combinations of surgery, radiotherapy (RT), and chemotherapy. Follow-up periods for disease-free patients are sometimes relatively short. The majority of patients present with locally advanced tumors; 10% to 30% have clinically positive regional nodes. The risk of local-regional recurrence after treatment is probably 20% to 30% or higher, depending on the extent of disease. The likelihood of distant dissemination is approximately 25% to 30% and the cure rate varies from roughly 20% to 50%. Better outcomes are observed in patients treated with craniofacial resection combined with pre- or postoperative RT alone or with adjuvant chemotherapy. This is probably due, in part, to selection bias. Patients with incompletely resectable tumors are best treated with definitive RT and adjuvant chemotherapy. CONCLUSION: The optimal treatment is craniofacial resection combined with adjuvant RT alone or with chemotherapy. The risk of relapse is relatively high and the probability of cure is modest. Patients with incompletely resectable tumors may sometimes be cured with definitive chemoradiation.

Carcinoma↗
PubMed2006

Giant cell tumor of bone.

OBJECTIVE: To discuss the treatment and outcomes for giant cell tumor (GCT) of bone. MATERIALS AND METHODS: Review of the pertinent literature. RESULTS: GCT is a rare benign bone lesion most often found in the extremities of women in the third and fourth decades of life. Surgery is the mainstay of treatment and usually consists of intralesional curettage; local control rates range from 80% to 90% after this procedure. Patients with extensive, recurrent, and/or biologically more aggressive tumors may require wide excision. A small subset of patients with incompletely resectable GCTs or with lesions that are surgically inaccessible may be treated with moderate-dose radiotherapy (45-50 Gy) and have a 65% to 80% likelihood of being locally controlled. CONCLUSION: The majority of patients with GCTs are effectively treated with intralesional curettage. Wide excision or radiotherapy is necessary to cure a relatively limited subset of patients with extensive, aggressive, and/or incompletely resectable GCTs.

Bone Neoplasms↗
PubMed2006

Lethal midline granuloma-nasal natural killer/T-cell lymphoma.

PURPOSE: The purpose of this paper is to discuss lethal midline granuloma (LMG)-nasal natural killer (NK) T-cell lymphoma (LMG-NTL). METHODS: Literature review. RESULTS: LMG is a rare entity that usually arises in the nasal cavity, exhibits a male preponderance, and has a wide age range. The majority of LMGs are LMG-NTLs. The optimal treatment of LMG-NTL is unclear and is most likely moderate-dose radiotherapy. The prognosis for patients with LMG-NTL is significantly worse than for patients with other types of head and neck non-Hodgkin lymphomas (NHL). The 5-year survival rate is approximately 20% but may be higher, depending on whether patients with less aggressive forms of NHL are included. Initial local-regional disease progression is the predominant pattern of treatment failure. Late failures after 5 years are uncommon. CONCLUSIONS: LMG-NTL is a rare nasal NK/T-cell lymphoma that can be difficult to distinguish from other benign and malignant entities. Its clinical course, however, is extremely aggressive. The patterns of failure suggest a role for more aggressive local-regional treatment, as well as more effective chemotherapy.

Diagnosis, Differential↗
PubMed2006

Definitive radiotherapy for juvenile nasopharyngeal angiofibroma.

OBJECTIVES: To update our experience with definitive radiotherapy (RT) for juvenile nasopharyngeal angiofibroma (JNA). METHODS: Twenty-two patients received definitive RT for advanced JNA between June 1975 and March 2003 and were followed from 2.0 to 30.2 years (median, 12.7 years). Total dose ranged from 30 to 36 Gy. RESULTS: Twenty of 22 patients (91%) remained locally controlled after RT; both patients who developed a local recurrence were salvaged so that the ultimate local control rate was 100%. No patient experienced a severe complication. CONCLUSION: Patients with advanced and/or recurrent JNA thought not to be amenable to complete resection with acceptable morbidity have a high likelihood of cure after RT with a low risk of complications.

Adolescent↗
PubMed2006

Aneurysmal bone cyst.

OBJECTIVES: The purpose of this article is to discuss the natural history, treatment, and outcomes for patients with aneurysmal bone cysts (ABC). METHODS: Review of the pertinent literature. RESULTS: ABCs account for 1% to 2% of all primary bone tumors, usually present in the first 2 decades of life, and exhibit a slight female preponderance. The majority of patients are treated with curettage with local control rates ranging from approximately 70% to 90%. Almost all patients with recurrences are salvaged by one or more additional operations. A small subset of patients is treated with marginal or wide excision and almost all are locally controlled. A few patients with incompletely resectable, aggressive, and/or recurrent ABCs are treated with low-dose (26-30 Gy) radiotherapy (RT) and are locally controlled in approximately 90% of cases. CONCLUSIONS: The mainstay of treatment is surgery and most patients are cured with one or more operations. A small subset of patients with incompletely resectable, aggressive, and/or recurrent ABCs may be cured with low-dose RT.

Bone Cysts, Aneurysmal↗
PubMed2006

Definitive radiotherapy for tonsillar squamous cell carcinoma.

PURPOSE: The purpose of this study is to update our experience with definitive radiotherapy (RT) for carcinoma of the tonsillar area. PATIENTS AND METHODS: There were 503 patients treated between October 1964 and May 2003 (potential follow-up for at least 2 years). Of these, 198 patients underwent a planned neck dissection and 57 patients received induction (18 patients) or concomitant (39 patients) chemotherapy. RESULTS: The 5-year local control rates were as follows: T1, 88%; T2, 84%; T3, 78%; and T4, 61%. Multivariate analysis revealed that local control was significantly influenced by T stage, primary site, and fractionation. Local control after RT for early stage cancers was higher for tonsillar fossa/posterior pillar tumors than for those arising from the anterior tonsillar pillar. The 5-year cause-specific survival rates were as follows: I, 100%; II, 86%; III, 84%; IVA, 73%; and IVB, 46%. Multivariate analysis revealed that cause-specific survival was significantly influenced by T stage, overall stage, neck dissection, race, and gender. The incidence of severe late complications was 9%. CONCLUSION: Based on our data and a review of the literature, definitive RT provides cure rates that are as good as those after surgery, and is associated with a lower rate of severe complications. Patients with lateralized tumors may be safely treated with ipsilateral field arrangements. Our limited experience with intensity modulated radiotherapy suggests that it is as efficacious as conventional RT.

Adult↗
PubMed2006

Preoperative radiotherapy alone or combined with chemotherapy followed by transanal excision for rectal adenocarcinoma.

OBJECTIVE: To evaluate the efficacy of preoperative radiotherapy (RT) and chemoradiation (CRT) followed by transanal excision (TAE) for rectal adenocarcinoma. METHODS: Thirty-two patients were treated between July 1988 and April 2004 and followed from 2 to 123 months (median, 27 months). RESULTS: The 3-year outcomes were: locoregional control, 79%; distant metastasis-free survival, 80%; cause-specific survival, 88%; and overall survival, 75%. Outcomes were better for patients with T1-T2 tumors and those who experienced a complete response to preoperative RT or CRT. Two patients (6%) had chronic RT proctitis after treatment. CONCLUSION: A select subset of patients with T2/T3 tumors will experience similar outcomes after preoperative RT or CRT and TAE compared with radical proctectomy. Reliably predictive clinicopathologic features to define this subgroup would best be elicited in the context of large prospective randomized trials, as would the optimal combination and schedule of systemic agents delivered in conjunction with preoperative RT. Patients who experience a complete response (cCR) after preoperative CRT are excellent candidates for TAE; those with less than a cCR have a less-favorable prognosis and are probably better treated with a low anterior resection or abdominal-perineal resection.

Adenocarcinoma↗