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Christopher G Morris

Publications and source records attributed to Christopher G Morris.

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

Delayed breast cellulitis: an evolving complication of breast conservation.

PURPOSE: Delayed breast cellulitis (DBC) is characterized by the late onset of breast erythema, edema, tenderness, and warmth. This retrospective study analyzes the risk factors and clinical course of DBC. METHODS AND MATERIALS: From 1985 through 2004, 580 sequential women with 601 stage T0-2N0-1 breast cancers underwent breast conserving therapy. Cases of DBC were identified according to accepted clinical criteria: diffuse breast erythema, edema, tenderness, and warmth occurring >3 months after definitive surgery and >3 weeks after radiotherapy. Potential risk factors analyzed included patient comorbidity, operative technique, acute complications, and details of adjunctive therapy. Response to treatment and long-term outcome were analyzed to characterize the natural course of this syndrome. RESULTS: Of the 601 cases, 16%, 52%, and 32% were Stage 0, I, and II, respectively. The overall incidence of DBC was 8% (50/601). Obesity, ecchymoses, T stage, the presence and aspiration of a breast hematoma/seroma, removal of >5 axillary lymph nodes, and arm lymphedema were significantly associated with DBC. The median time to onset of DBC from the date of definitive surgery was 226 days. Ninety-two percent of DBC patients were empirically treated with antibiotics. Fourteen percent required more invasive intervention. Twenty-two percent had recurrent episodes of DBC. Ultimately, 2 patients (4%) underwent mastectomy for intractable breast pain related to DBC. CONCLUSION: Although multifactorial, we believe DBC is primarily related to a bacterial infection in the setting of impaired lymphatic drainage and may appear months after completion of radiotherapy. Invasive testing before a trial of antibiotics is generally not recommended.

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

Whole-abdomen radiotherapy for non-Hodgkin's lymphoma using twice-daily fractionation.

PURPOSE: To report the tolerability and efficacy of twice-daily whole-abdomen irradiation (WAI) for non-Hodgkin's lymphoma (NHL). METHODS AND MATERIALS: Of 123 patients treated for NHL with WAI, 37% received previous chemotherapy, 28% received WAI as part of comprehensive lymphatic irradiation (CLI), and 32% received WAI for palliation. The median dose to the whole abdomen was 25.0 Gy, followed by a median tumor boost of 9.8 Gy in 58 patients. Fractionation was 1.0 Gy once daily (54%) or 0.8 Gy twice daily (46%). Blood counts were measured weekly. RESULTS: At a median follow-up of 4.3 years, local control was 72% and overall survival was 55% at 5 years. Median time of WAI was 42 days for once-daily treatment and 32 days for twice-daily treatment. Patients receiving twice-daily WAI did not have a significantly higher rate of acute side effects (e.g., nausea, diarrhea, platelet or red blood cell toxicity). Overall, acute thrombocytopenia was the most frequent side effect of treatment; 24 of 96 patients (25%) with available hematologic data had Grade 3+ toxicity. There was no acute Grade 3 gastrointestinal toxicity and no late small bowel obstruction. Multiple regression indicated that patients with four or less involved sites and disease size < or =6 cm had improved local control and overall survival. CONCLUSIONS: Twice-daily WAI using 0.8 Gy/fraction does not appear to have any greater toxicity compared with once-daily treatment using 1 Gy/fraction. Small doses per fraction (0.8-1 Gy/fx) are effective, tolerated well in the acute setting, and associated with a low rate of late toxicity.

Abdomen↗
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

Second malignancies after prostate brachytherapy: incidence of bladder and colorectal cancers in patients with 15 years of potential follow-up.

PURPOSE: To report the incidence of second bladder and colorectal cancers after prostate brachytherapy. METHODS AND MATERIALS: This review included 125 patients treated with I-125 brachytherapy alone, and 223 patients who received supplemental external beam radiation therapy. Median follow-up was 10.5 years. Patients were followed for the development of lower genitourinary and colorectal cancers. Second malignancies arising five years after radiation therapy were defined as being potentially associated with treatment; observed rates were then compared with age-matched expected rates according to Surveillance, Epidemiology, and End Results data. RESULTS: Five years out of treatment, there were 15 patients with a second solid tumor, including bladder cancer (n = 11), colorectal cancer (n = 3), and prostatic urethra cancer (n = 1). The incidence of second malignancy was no different in patients treated with brachytherapy alone (1.6%) vs. those receiving external beam radiotherapy (5.8%, p = 0.0623). There were more observed bladder cancers compared with those expected (relative risk, 2.34, 95% confidence interval 0.96-3.72; absolute excess risk 35 cancers per 10,000 patients). Relative risk did not significantly change over increasing follow-up intervals up to 20 years after treatment. CONCLUSIONS: There may be an increased but small risk of developing a second malignancy after radiation therapy for prostate cancer. This outcome could be related to radiation carcinogenesis, but more vigilant screening and thorough workup as a result of radiation side effects and predisposing conditions (e.g., genetic and environmental factors) in many of the patients found to have second malignancies likely contributed to the higher number of observed malignancies than expected.

Adult↗
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

The impact of heterogeneity correction on dosimetric parameters that predict for radiation pneumonitis.

PURPOSE: To determine if heterogeneity correction significantly affects commonly measured dosimetric parameters predicting pulmonary toxicity in patients receiving radiation for lung cancer. METHODS AND MATERIALS: Sixty-eight patients treated for lung cancer were evaluated. The conformal treatment technique mostly employed anteroposterior/posterior-anterior fields and off-cord obliques. The percent total lung volume receiving 20 Gy or higher (V20) and mean lung dose (MLD) were correlated with the incidence of radiation pneumonitis. Parameters from both heterogeneity-corrected and heterogeneity-uncorrected plans were used to assess this risk. RESULTS: Univariate analysis revealed a significant correlation between the development of radiation pneumonitis and both V20 and MLD. A best-fit line to a plot of V20 from the homogeneous plan against the corresponding V20 heterogeneous value produced a slope of 1.00 and zero offset, indicating no difference between the two parameters. For MLD, a similarly significant correlation is seen between the heterogeneous and homogeneous parameters, indicating a 4% difference when correcting for heterogeneity. A significant correlation was also observed between the MLD and V20 parameters (p < 0.0001). CONCLUSIONS: A high degree of correlation exists between heterogeneity-corrected and heterogeneity-uncorrected dosimetric parameters for lung and the risk of developing pneumonitis. Either V20 or MLD predicts the pneumonitis risk with similar effect.

Adult↗
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

Adjuvant radiotherapy in the management of soft tissue sarcoma involving the distal extremities.

OBJECTIVE: Treating soft tissue sarcoma (STS) of the distal extremity is challenging in terms of achieving local control and avoiding complications. It is now accepted that a limb conserving approach provides equivalent survival when compared with radical amputation. METHODS: Twenty-three patients with STS involving the hand-wrist or foot-ankle complex received adjuvant radiotherapy (RT) for limb conservation and were evaluated to determine if local control, survival, and functional ability were achieved. The median patient age was 64 and median time of follow-up was 11 years. The location of the sarcoma included the hand (n = 12) or foot (n = 11). Seven patients received preoperative RT (median dose, 50.40 Gy) and 16 patients received postoperative RT (median dose, 64.80 Gy). Patients treated preoperatively and 9 treated postoperatively received hyperfractionated RT at 1.2 Gy twice-daily. Seven patients treated postoperatively received conventional daily-fractionated treatment. RESULTS: Twenty of 23 patients received RT at first presentation; 3 were treated for locally recurrent disease. The 5- and 10-year rates of local control were 91%. The 10-year rates of cause-specific and absolute survival were 96% and 91%, respectively. The 5- and 10-year rates of distant metastases-free survival were 87%. The ultimate limb-conservation rate was 91%. No patient required an amputation because of local recurrence or treatment complications. Function of the hand or foot was maintained for all of the 21 patients for whom limb-conserving treatment was achieved. CONCLUSIONS: Combined modality therapy with limb-conserving surgery and adjuvant RT achieves excellent local control (91%) and potential overall survival (91%) rates with excellent functional outcome.

Aged↗
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

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↗
PubMed2006

Hypothyroidism when the thyroid is included only in the low neck field during head and neck radiotherapy.

OBJECTIVE: The minimum dose required to electively irradiate all of part of the low neck for squamous cell carcinoma of the oropharynx is 50 Gy in 25 fractions or its radiobiological equivalent. The purpose of our study is to determine the incidence of hypothyroidism when the thyroid is treated only in the low-neck radiotherapy (RT) field to approximately 50 Gy. METHODS AND MATERIALS: 390 patients with oropharyngeal carcinoma received RT between 1990 and 2000, had no prior thyroid disease or surgery, and had RT involving the standard anterior low-neck field including the thyroid with a dose equivalent to 50 Gy at 2Gy/fx with or without a boost to a portion of the field to 60 to 70 Gy. The end point was hypothyroidism defined as thyroid stimulating hormone (TSH) above the upper limit of the normal range. RESULTS: As we did not routinely monitor TSH during this study, it was obtained in 169 of 390 patients. Median follow-up on all 390 patients was 6.1 years. The incidence of hypothyroidism was calculated for 2 groups: 169 patients with TSH data and the total population of 390 patients. For both analyses, patients were censored at last follow-up if the TSH level was normal, or if TSH was not checked. The incidence of hypothyroidism at 5 years was 31% for all 390 patients and 54% for the subset of 169 patients with TSH data. Adjuvant chemotherapy and/or planned neck dissection may be associated with a small increased risk of hypothyroidism. CONCLUSIONS: Including the thyroid in the low-neck field to 50 Gy results in hypothyroidism in 30% to 50% of patients at 5 years, suggesting that the threshold for this complication is <50 Gy.

Carcinoma, Squamous Cell↗
PubMed2006

Surgery and postoperative radiotherapy for squamous cell carcinoma of the larynx and pharynx.

OBJECTIVE: To determine the rates of local-regional control, survival, and complications for patients treated with postoperative radiation for squamous carcinomas of the larynx, hypopharynx, and oropharynx. METHODS: There were 295 patients with previously untreated squamous cell carcinomas of the larynx (n = 199), hypopharynx (n = 80), and oropharynx (n = 16) treated postoperatively with radiotherapy (RT). RESULTS: Five-year local-regional control rates according to site and pathologic American Joint Committee on Cancer (AJCC) stage were: stage III larynx, 89% versus stage IVA larynx, 85% (P = 0.33); stage III oropharynx/hypopharynx, 76% versus stage IVA oropharynx/hypopharynx, 79% (P = 0.72). Local-regional control rates steadily declined as the number of indications for administering postoperative RT increased. Five-year absolute survival rates versus pathologic AJCC stage for the entire group were: stage III 59% and stage IVA 40% (P = 0.40). CONCLUSION: Rates of local-regional control, survival, and complications support the use of postoperative radiation in selected patients. Tumor control and survival will hopefully improve further with the addition of chemotherapy to postoperative radiation.

Adult↗
PubMed2006

Definitive radiotherapy for nasopharyngeal carcinoma.

PURPOSE: We sought to report the outcomes after definitive radiotherapy (RT) for nasopharyngeal carcinoma. METHODS: Between March 1983 and November 2003, 82 patients were treated with curative intent and followed from 0.2 to 22 years (median, 5 years). Follow-up on living patients ranged from 2.8 to 22 years (median, 10.8 years). Thirty-two patients (39%) were treated once daily, 45 patients (55%) were treated with hyperfractionation, and 5 patients (6%) were treated with the concomitant boost technique. Eight patients (10%) received intensity-modulated radiotherapy. Thirty-one patients (38%) received induction (17 patients) or concomitant (14 patients) chemotherapy. Fourteen patients (17%) underwent a planned neck dissection. RESULTS: The 5-year outcomes after treatment were: local control, 78%; regional control, 90%; local-regional control, 76%; distant metastasis-free survival, 80%; cause-specific survival, 66%; and survival, 57%. The impact of T-stage, N-stage, overall stage, World Health Organization class, fractionation schedule, and adjuvant chemotherapy were evaluated in a multivariate analysis of various outcomes. Only N-stage and World Health Organization class impacted regional control. CONCLUSIONS: The likelihood of cure after RT is relatively high. Although the likelihood of cure diminished with increasing stage, none of the parameters evaluated significantly influenced outcomes aside from N-stage and WHO class.

Adolescent↗