Extent of neck dissection for patients with clinical N1 oral cancer.

BACKGROUND: No clear consensus has been reached on the indication of supraomohyoid neck dissection (SOHND) for clinically positive lymph-node metastasis. PATIENTS: Consecutive 100 patients with previously untreated oral cancer treated at Kobe University Hospital were included in this study. All patients were clinically staged as anyTN1M0 and underwent radical dissection of the primary site and level I-V neck dissection as the initial treatment. RESULTS: None of the 100 patients had pathological lymph-node metastasis (pLN) to level V. pLN to level IV was observed in two patients with tongue cancer in whom clinical lymph-node metastasis was preoperatively observed at level II. CONCLUSIONS: Level V may be excluded in the neck dissection for patients with N1 oral cancers. Level IV dissection should be considered in the patient with tongue cancer and clinical lymph-node metastasis at level II.

Long-Term Effects on Volume Change in Musculocutaneous Flaps after Head and Neck Reconstruction.

OBJECTIVE: Musculocutaneous flap reconstruction surgery is one of the standard procedures following head and neck cancer resection. However, no previous studies have classified flaps in terms of muscle and fat or examined them after long-term follow-up. The purpose of this study was to estimate the fat and muscle volume changes in musculocutaneous flaps during long-term follow-up. METHODS: We conducted a retrospective analysis of 35 patients after musculocutaneous flap reconstruction. The total, fat, and muscle volumes of the musculocutaneous flaps were measured using 3-dimensional images. Changes in flap volumes over time (1 month, 1 year [POY1], and 5 years [POY5] postoperatively) were assessed. Flap persistence was calculated using flap volumes at 1 month after reconstruction for reference. RESULTS: Flap persistence at POY5 was 42.0% in total, 64.1% in fat, and 25.4% in muscle. Muscle persistence was significantly decreased (p < 0.0001). In a multiple regression analysis, decreased body mass index (BMI) of ≥ 5% influenced fat persistence less than muscle persistence at POY1; however, there was no significant difference at POY5. Postoperative radiation therapy was associated with a significant decrease in total flap persistence at POY1 (p = 0.046) and POY5 (p = 0.0097). Muscle persistence significantly decreased at POY5 (p = 0.0108). Age significantly influenced muscle volume at POY1 (p = 0.0072). CONCLUSION: Reconstruction flaps are well-preserved with high fat-to-muscle ratios. Recommendations for weight maintenance are necessary for patients less than 2 years after surgery due to the influence of BMI on fat persistence. Radiation therapy is necessary for some patients based on their disease state. Intensity-modulated radiation therapy can be offered to reduce scattering irradiation to normal tissues.

The maximum standardized uptake value increment calculated by dual-time-point 18F-fluorodeoxyglucose positron emission tomography predicts survival in patients with oral tongue squamous cell carcinoma.

The aim of this study was to investigate the prognostic value of dual-time-point (DTP) 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) imaging in primary oral tongue squamous cell carcinoma (OTSCC). The study included 52 patients who underwent preoperative 18F-FDG PET scans at two time points, namely 1 h and 2 h after injection. The following PET parameters were calculated: maximum standardized uptake value (SUVmax) for both time points (SUV early, SUV delayed); retention index (RI); and SUVmax increment (ΔSUVmax). Receiver operating characteristic (ROC) curve analysis was performed to define the optimal cutoff point for these parameters. Overall survival was calculated using the Kaplan-Meier method. Prognostic factors for patients with OTSCC were evaluated using the univariate log-rank test and a multivariate Cox proportional hazards model. ROC analysis revealed that the area under the curve was higher and more accurate for ΔSUVmax than for the other parameters. Additionally, patients with a ΔSUVmax ≥0.9 had significantly worse survival outcomes (28.9% vs 92.6%; p < 0.01). Univariate analysis showed that prognosis was significantly correlated with clinical T stage, local recurrence, perineural invasion, vascular invasion, and PET parameters (p < 0.05 for all). Multivariate analysis showed that local recurrence (hazard ratio = 3.60; p = 0.02) and ΔSUVmax (hazard ratio = 8.43; p < 0.01) were independent prognostic factors. ΔSUVmax determined using DTP 18F-FDG PET may be an additional prognostic factor in OTSCC patients.

FDG-PET/contrast-enhanced CT as a post-treatment tool in head and neck squamous cell carcinoma: comparison with FDG-PET/non-contrast-enhanced CT and contrast-enhanced CT.

OBJECTIVE: To evaluate the accuracy of PET/CT using (18)F-fluorodeoxyglucose (FDG) with IV contrast for suspected recurrent head and neck squamous cell carcinoma (HNSCC). METHODS: One hundred and seventy patients previously treated for HNSCC underwent PET/CT, consisting of non-contrast-enhanced and contrast-enhanced CT, to investigate suspected recurrence. Diagnostic performance of PET/contrast-enhanced CT (PET/ceCT), PET/non-contrast-enhanced CT (PET/ncCT) and contrast-enhanced CT (ceCT) for local or regional recurrence, distant metastasis, overall recurrence and second primary cancer was evaluated. The reference standard included histopathology, treatment change and imaging follow-up. RESULTS: The patient-based areas under the receiver operating characteristic curves (AUC) for ceCT, PET/ncCT and PET/ceCT were 0.82, 0.96 and 0.98 for local recurrence, 0.73, 0.86 and 0.86 for regional recurrence, 0.86, 0.91 and 0.92 for distant metastasis, 0.72, 0.86 and 0.87 for overall recurrence, and 0.86, 0.89 and 0.91 for a second primary cancer. Both PET/ceCT and PET/ncCT statistically showed larger AUC than ceCT for recurrence, and the difference between PET/ceCT and PET/ncCT for local recurrence reached a significant level (p = 0.039). The accuracy of PET/ceCT for diagnosing overall recurrence was high, irrespective of the time interval after the last treatment (83.3-94.1 %). CONCLUSION: FDG-PET/CT was a more accurate HNSCC restaging tool than ceCT. The added value of ceCT at FDG-PET/CT is minimal. KEY POINTS: • FDG-PET/CT is a more accurate post-treatment surveillance tool than ceCT for HNSCC. • FDG-PET/ceCT was useful, irrespective of the time interval after the last treatment. • FDG-PET/ceCT showed high negative predictive value and limited positive predictive value. • The added value of ceCT at FDG-PET/CT is minimal and likely not clinically relevant.

Incidence of Venous Thromboembolism After Oral Oncologic Surgery With Simultaneous Reconstruction.

PURPOSE: Patients with oral cancer who undergo resection with simultaneous reconstruction are presumed to be at high risk for developing venous thromboembolism (VTE) according to current criteria. The primary purpose of this retrospective study was to report the incidence of VTE after oral cancer surgery requiring primary reconstruction and to identify the potential risk factors for VTE in this population. MATERIALS AND METHODS: This retrospective study evaluated 133 consecutive patients who had undergone oral cancer resection with simultaneous reconstruction from April 2007 through December 2014. Bilateral lower-extremity venous duplex ultrasonography (VDUS) was routinely performed 2 days after surgery. Pulmonary embolism was confirmed with computed tomography. The Caprini risk score (CRS) was obtained for each patient. Patients with and without VTE were compared using the χ2 test and Student t test with some variables. Univariate predictors associated with VTE were entered into a multivariate logistic regression analysis. A P value less than .05 was regarded as indicating statistical significance. RESULTS: The incidence of VTE after oral oncologic surgery with simultaneous reconstruction was 26.3% (35 of 133 patients): deep vein thrombosis (DVT) and pulmonary embolism occurred in 2.3% (3 of 133) and DVT alone was found in 24.0% (32 of 133). Multivariate logistic regression analysis showed that only a high CRS was statistically relevant to VTE occurrence. CONCLUSIONS: Because a high incidence of VTE was found after major oral and maxillofacial surgery, lower-extremity VDUS should be undertaken in patients who undergo oral cancer surgery with simultaneous reconstruction, especially those with a high CRS.

Does salivary duct repositioning prevent complications after tumor resection or salivary gland surgery?

PURPOSE: Tissue that is resected for the treatment of oral tumors often includes salivary gland ducts. At their institution, the authors conserve and transfer as much of the salivary duct as possible during these procedures to avoid obstructive complications. Differentiating these obstructive complications from a metastatic node can be challenging and can confound subsequent oncologic management. This study compared and examined the effectiveness of salivary duct repositioning in decreasing the incidence of obstructive complications. MATERIALS AND METHODS: Cases of oromandibular disease treated with salivary duct resection at Kobe University Graduate School of Medicine from 2008 to 2013 were retrospectively analyzed. Thirty-two cases (25 patients) of Wharton duct resection and 31 cases (31 patients) of Stensen duct resection were included. The incidence of complications after salivary duct repositioning, duct ligation, and retention of the sublingual gland around the Wharton duct was compared. RESULTS: Wharton ducts were repositioned in 30 cases and ligated in 2 cases. Complications, including oral swelling at the Wharton duct, were observed in 5 cases of repositioning and 2 cases of ligation. Stensen ducts were repositioned in 9 cases and ligated in 22 cases. The only complication reported was a single case of salivary fistula after ligation. CONCLUSIONS: Salivary duct repositioning is performed to prevent blockage of physiologic salivary discharge. Complications were more frequently associated with Wharton ducts than with Stensen ducts because of the unique physiologic and anatomic characteristics of the Wharton duct. Repositioning of the salivary duct is a suitable method for preventing complications associated with the Wharton duct.

What Is the Appropriate Antibiotic Administration During Tooth Extractions in Patients Receiving High-Dose Denosumab?

PURPOSE: Medication-related osteonecrosis of the jaw (MRONJ) occasionally occurs following tooth extractions in cancer patients receiving denosumab (Dmab). However, there are currently no established guidelines for perioperative antibiotic administration during tooth extraction in these patients. The primary objective was to develop guidelines for the dose and frequency of antibiotics during tooth extraction by investigating the correlation between the current status of antibiotic administration and the development of MRONJ. METHODS: This study included 68 cancer patients receiving high-dose Dmab who had tooth extractions between 2012 and 2022 at 10 hospitals. The relationship between the way of perioperative antibiotic administration and the development of MRONJ was analyzed. A P-value < .05 was considered significant. RESULTS: There was considerable variability across hospitals and surgeons regarding the type, dosage, and duration of antibiotic administration. Amoxicillin (AMPC) was the most commonly used antibiotic. Focusing exclusively on teeth extracted under AMPC administration, MRONJ developed in 21 out of 123 teeth (17.0%). No significant relationship was found between the development of MRONJ and the dosage or duration of perioperative AMPC administration. CONCLUSION: Perioperative antibiotic administration alone may not be sufficient to prevent MRONJ. Therefore, a single preoperative dose is likely adequate for effective and appropriate AMPC administration.　.

Oral squamous cell carcinoma with multiple neck metastases--cases with more than ten pathologically positive lymph nodes in the unilateral side.

PURPOSE: The purpose of this study is to know an outcome of the treatment for oral squamous cell carcinoma having more than 10 unilateral pathologically positive lymph nodes (pN)s. PATIENTS AND METHODS: We reviewed 212 primary cases of oral squamous cell carcinoma that visited our hospital from January 1999 to December 2011 and underwent resection of the primary tumor with neck dissection. The patients were classified into 3 categories of pN0, pN1-9, and pN ≥ 10 cases, and an outcome of pN ≥ 10 was studied specifically in comparison with the other categories. RESULTS: Of the patients studied, 103 cases (48.6%) were pN0, 103 cases (48.6%) were pN1-9, and 6 cases (2.8%) were pN ≥ 10. The pN ≥ 10 group, which had positive nodes of 10 to 30 on the ipsilateral side, was predominantly male and had no cases of well-differentiated squamous cell carcinoma. Extracapsular spread (ECS) was found in all pN ≥ 10 cases, and postoperative distant metastasis occurred in cases with ECS, which was localized in levels higher than III. The proportion of distant metastasis was 0% (0 cases) in pN0, 8.7% (9 cases) in pN1-9, and 66.7% (4 cases) in pN10. Overall survival rate in pN ≥ 10 was 20.8%, whereas it was 89.0% in pN0, and 34.9% in pN1-9. CONCLUSION: Oral squamous cell carcinoma having multiple neck metastases (pN ≥ 10) had a poor prognosis because the proportion of distant metastasis was higher in comparison with the other groups of pN0 and pN1-9.

Aortic Rupture due to Co-localization of Aortic Intimal Myofibroblastic Sarcoma and Urothelial Carcinoma: A Unique Case Report.

We herein report a unique case of aortic rupture due to co-localization of aortic intimal myofibroblastic sarcoma (IMFS) and urothelial carcinoma (UC). A 76-year-old man who was being followed up after surgery for UC 5 years earlier developed aortic rupture and underwent emergency surgery. Intraoperatively, a tumorous mass on the luminal side of the aortic arch was found near the rupture. A histopathological analysis of the mass revealed aortic IMFS. Furthermore, co-localization of IMFS and UC cells was found near the rupture. The fragility of the aortic wall due to co-localization of IMFS and UC was believed to contribute to the aortic rupture.

Effect of size difference between hemiglossectomy and reconstruction flap on oral functions: A retrospective cohort study.

BACKGROUND AND OBJECTIVE: Forearm free flaps are used after hemiglossectomy. However, no investigation has been performed on whether oral functions are better preserved when sizes of the resection and reconstruction flap are exact matches, or whether the size of the resection should be changed. We aimed to retrospectively examine whether size differences between the resection and reconstruction flap affect speech and swallowing functions postoperatively, and to determine whether there are more favorable flap size ratios. METHODS: This is a retrospective cohort study of patients undergoing hemiglossectomy using a forearm free flap between 2006 and 2016 at Kobe University Hospital, Japan. The effect of size difference between the resection and reconstruction flap on maintained oral function was assessed. Speech and swallowing functions were assessed, and their correlation with the ratio of the flap size to that of the resected area was determined. With these data, distribution maps of the relationship between the functional level and reconstructed dimension ratio were prepared. The more suitable reconstructed dimension ratio was examined and evaluated. The Fisher exact test, Kruskal-Wallis test, and Scheffe test were used in statistical analyses. RESULTS: Eighty-eight patients underwent hemiglossectomy using a forearm free flap during a 10-year period. Of these cases, 66 patients were included in this study, while 22 were excluded. The ratio of the area of the reconstruction flap to that of the resection site was 0.59-2.79 (median: 1.61). Sixty patients had flaps greater than the resection area, whereas 6 had smaller flaps. Significant differences were found in speech intelligibility and swallowing function when the reconstructed dimension ratio was categorized as follows: ≤1.3, 1.3-1.8, and ≥1.8. CONCLUSION: Our findings suggest that postoperative deterioration of oral functions after hemiglossectomy could be reduced if reconstruction is performed using a forearm free flap with a surface area 1.3 to 1.8 times greater than that of the resection area.

Computed Tomographic Evaluation of Posttreatment Soft-Tissue Changes by Using a Lymphedema Scoring System in Patients with Oral Cancer.

BACKGROUND: This study aimed to evaluate posttreatment soft-tissue changes in patients with oral cancer with computed tomography (CT). To accomplish that purpose, a scoring system was established, referring to the criteria of lower leg lymphedema (LE). METHODS AND RESULTS: One hundred and six necks in 95 patients who underwent oral oncologic surgery with neck dissection (ND) were analyzed retrospectively using routine follow-up CT images. A two-point scoring system to evaluate soft-tissue changes (so-called "LE score") was established as follows: Necks with a "honeycombing" appearance were assigned 1 point. Necks with "taller than wide" fat lobules were assigned 1 point. Necks with neither appearance were assigned 0 points. Comparisons between patients with LE score ≥1 and LE score = 0 at 6 months postoperatively were performed using the Fisher exact test for discrete variables and the Mann-Whitney U test for continuous variables. Univariate predictors associated with posttreatment changes (i.e., LE score ≥1 at 6 months postoperatively) were entered into a multivariate logistic regression analysis. Values of p < 0.05 were considered to indicate statistical significance. The occurrence of the posttreatment soft-tissue changes was 32%. Multivariate logistic regression analysis showed that postoperative radiation therapy (RT) and bilateral ND were potential risk factors of posttreatment soft-tissue changes on CT images. CONCLUSIONS: Sequential evaluation of "honeycombing" and the "taller than wide" appearances on routine follow-up CT revealed the persistence of posttreatment soft-tissue changes in patients who underwent oral cancer treatment, and those potential risk factors were postoperative RT and bilateral ND.

Single-stage reconstruction for buccal mucosa tumor resection including the labial commissure using a facial artery musculomucosal flap and a vermilion advancement flap.

Resection of buccal mucosa tumors may occasionally involve the labial angle and peripheral skin. Reconstruction is required when the resection involves more than one-third of the lip. We describe a single-stage reconstruction using a facial artery musculomucosal (FAMM) flap and a vermilion advancement flap after buccal mucosa resection including the labial angle. A 62-year-old woman with carcinoma in situ of the buccal mucosa underwent tumor resection. The resection included the right labial angle and peripheral skin. The resection did not lead to a massive lip defect, but a wide defect resulted on the mucosal side. The defect on the mucosal side was reconstructed using a FAMM flap, while the vermilion defect was covered using a vermilion advancement flap. Reconstruction performed using the FAMM flap and vermilion advancement flap produced aesthetically and functionally satisfactory outcomes.

Prognosis of oral squamous cell carcinoma patients with level IV/V metastasis: An observational study.

PURPOSE: The objectives of this study were to retrospectively describe the characteristics and outcomes of patients with oral squamous cell carcinoma (OSCC) with level IV/V metastases, and to evaluate the multivariate relationships among potential risk factors for metastasis and prognosis. MATERIALS AND METHODS: We evaluated 291 patients (178 men and 113 women; mean age, 65.9 ± 13.5 years). Clinicopathological data, time of development of level IV/V metastases, and clinical course were investigated. RESULTS: Twenty-three patients (7.9%) developed level IV/V metastases. The 3-year overall survival rates when level IV/V metastasis first developed were 27.3% upon initial treatment, 57.1% when metachronous neck metastasis developed, and 40.0% when the tumor recurred. Oral tongue tumor subsite, high N staging, neck dissection when metachronous neck metastasis developed, as well as recurrence were independent risk factors for level IV/V metastasis. CONCLUSION: We demonstrate here the multivariate relationships among the risk factors indicated above for level IV/V metastasis and their prognostic significance for patients with OSCC. Oral tongue tumors, high N staging, and neck dissection upon the occurrence of metachronous neck metastasis or recurrence were risk factors for level IV/V metastasis and positive extracapsular spread, presence of multiple lymph metastases, and moderate or poor differentiation were poor prognostic factors.

Upregulated Expression of Transient Receptor Potential Cation Channel Subfamily V Receptors in Mucosae of Patients with Oral Squamous Cell Carcinoma and Patients with a History of Alcohol Consumption or Smoking.

OBJECTIVES: Transient receptor potential cation channel (subfamily V, members 1-4) (TRPV1-4) are expressed in skin and neurons and activated by external stimuli in normal mucosae of all oral cavity sites. The oral cavity is exposed to various stimuli, including temperature, mechanical stimuli, chemical substances, and changes in pH, and, notably, the risk factors for oncogenic transformation in oral squamous epithelium are the same as the external stimuli received by TRPV1-4 receptors. Hence, we examined the relationship between oral squamous cell carcinoma (SCC) and TRPV1-4 expression. MATERIALS AND METHODS: Oral SCC patients (n = 37) who underwent surgical resection were included in this study. We investigated the expression of TRPV1-4 by immunohistochemical staining and quantification of TRPV1-4 mRNA in human oral mucosa. In addition, we compared the TRPV1-4 levels in mucosa from patients with SCC to those in normal oral mucosa. RESULTS: The receptors were expressed in oral mucosa at all sites (tongue, buccal mucosa, gingiva, and oral floor) and the expression was stronger in epithelia from patients with SCC than in normal epithelia. Furthermore, alcohol consumption and tobacco use were strongly associated with the occurrence of oral cancer and were found to have a remarkable influence on TRPV1-4 receptor expression in normal oral mucosa. In particular, patients with a history of alcohol consumption demonstrated significantly higher expression levels. CONCLUSION: Various external stimuli may influence the behavior of cancer cells. Overexpression of TRPV1-4 is likely to be a factor in enhanced sensitivity to external stimuli. These findings could contribute to the establishment of novel strategies for cancer therapy or prevention.

Retrospective study of treatment outcomes after postoperative chemoradiotherapy in Japanese oral squamous cell carcinoma patients with risk factors of recurrence.

BACKGROUND: The purpose of this study was to investigate the feasibility of postoperative concomitant chemoradiotherapy (CRT) with cisplatin (CDDP), and compare the prognosis in 3 groups-without postoperative therapy (S-only), with radiotherapy (RT) alone (S+RT), and with CRT (S+CRT)-in oral squamous cell carcinoma (OSCC) patients at high risk of recurrence. METHODS: Clinicopathologic data and treatment modality were investigated. Endpoints evaluated were locoregional control (LRC), relapse-free survival, overall survival (OS), and type of recurrence. RESULTS: The S+CRT group was associated with a better LRC rate than the S-only (P < .001) and S+RT groups (P = .044). However, there was no significant difference in OS rates between the S+RT and S+CRT groups. CONCLUSION: The addition of concomitant CDDP to postoperative RT improved LRC. However, there may be no benefit from the addition of concomitant CDDP to postoperative RT for improvement of distant metastasis and OS rates in OSCC patients.

Induced Pluripotent-stem-cell Related Genes Contribute to De-differentiation in Oral Squamous Cell Carcinoma.

BACKGROUND/AIM: Cancer stem cells are suspected to contribute to malignancy in tumors. Hypoxia affects cell differentiation and induces stem-cell-like characteristics in malignancies. Induced pluripotency was demonstrated in mouse fibroblasts by reprogramming with four transcriptional factors: Oct3/4, Sox2, c-Myc, and Klf4. Conversely, oncogenic transformations frequently express transcriptional factors and Nanog. Therefore, cancer cells present some similarities with induced pluripotent stem (iPS) cells. MATERIALS AND METHODS: We investigated the expression of iPS-related genes in vitro and in clinical samples to identify their relationships with hypoxia and tumorigenesis. RESULTS: Oral squamous cell carcinoma (SCC) cells were used to show that expression levels of Oct3/4, Sox2, and Nanog were significantly increased in hypoxic condition in vitro and in moderately- and poorly-differentiated samples. CONCLUSION: We propose that Oct3/4, Sox2 and Nanog are associated with tumor hypoxia characterized in oral SCC and that these factors may also contribute to the undifferentiated potency observed in oral SCC clinically.

Decreased mitochondrial copy numbers in oral squamous cell carcinoma.

BACKGROUND: Mitochondrial dysfunction and altered respiration have long been suspected to affect the development and progression of cancer. Although quantitative changes in mitochondrial DNA (mtDNA) have been reported in head and neck squamous cell carcinoma (SCC), differences in mtDNA copy numbers between normal and cancerous tissues from same patients have not been assessed. METHODS: We compared mtDNA copy numbers and expressions of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) and mitochondrial transcription factor A (TFAM) between normal mucous membrane and cancerous tissues resected from 35 patients with oral SCC, using TaqMan quantitative real-time polymerase chain reaction (PCR) and immunohistochemical staining. RESULTS: We found mtDNA copy numbers and expressions of PGC-1α and TFAM were decreased in cancerous tissues compared with normal tissues from the same patients. CONCLUSION: The PGC-1α-TFAM mitochondrial pathway may be associated with malignant potential in human oral SCC, and could be an attractive therapeutic target. © 2016 Wiley Periodicals, Inc. Head Neck 38:1170-1175, 2016.

Cause and occurrence timing of osteoradionecrosis of the jaw: a retrospective study focusing on prophylactic tooth extraction.

PURPOSE: This retrospective study aimed to analyze the relationship between tooth extraction and osteoradionecrosis (ORN) occurrence. The irradiation field, dose, and time interval between radiotherapy (RT) and ORN were reviewed. We also discuss appropriate guidelines for prophylactic tooth extraction. METHODS: A total of 33 patients treated for grade ≥2 (clinical) ORN in our department from 2002 to 2014 were enrolled. The following epidemiological data were retrospectively gathered: age, sex, histological diagnosis, primary tumor sites, radiation dose, chemotherapy, site of ORN, relationship between tooth extraction and ORN occurrence, and time interval between tooth extraction and the initiation or end of RT. RESULTS: Twenty-one percent of ORN cases resulted from tooth extraction. The most common site of ORN (82 %) was the mandibular molar region. About half of ORN cases (49 %) occurred within 2 years after RT. All patients who received tooth extraction after RT developed ORN (100 %) independently of time interval between tooth extraction and the end of RT (median interval, 37.5 months; range, 27-120 months). In contrast, only 50 % of patients who received tooth extraction before RT developed ORN. There may have been an association between the irradiation field and the site of ORN development CONCLUSIONS: ORN occurrence due to tooth extraction was 21 %. Occurrence timing of ORN did not depend on time interval between tooth extraction and the end of RT. The irradiation field is certainly related to the site of ORN; therefore, prophylactic tooth extraction should be performed in consideration of the proposed radiation field and dose.

Comparison between primary closure and skin grafts of the free fibula osteocutaneous flap donor site.

PURPOSE: This study aimed to compare the size of skin paddles, the postoperative course, and donor site complications between primary closure and skin grafts of the free fibula flap donor site. METHODS: Thirty-five consecutive patients were enrolled. Medical records were retrospectively reviewed for risk factors for delayed healing, size of skin paddles, time to resumption of gait with a mobility aid and self-ambulation, early donor site morbidity, and late donor site complaints. RESULTS: The harvested skin paddles were significantly wider in the skin graft group than in the primary closure group (P = 0.02), with no difference in length (P = 0.1). The difference in time to resuming gait with a mobility aid was also significant (P = 0.01), but not the time to self-ambulation (P = 0.9). Two early donor site morbidities (5.7 %) and 12 late donor site complaints (34.3 %) were found. No significant difference in the incidence of early donor site morbidity was observed between two groups. Occurrence of late donor site complaints was not affected by any risk factors. CONCLUSIONS: The width of the harvested skin paddle, but not the length, is one of factors involved in donor site closure. Resumption of gait with a mobility aid, but not self-ambulation, may be delayed in skin graft patients.