FDG-PET/CT-guided intensity modulated head and neck radiotherapy: a pilot investigation

BACKGROUND: 2-deoxy-2[(18)F]fluoro-D-glucose-positron emission tomography (FDG-PET) imaging can be registered with CT images and can potentially improve neck staging sensitivity and specificity in patients with head and neck squamous cell cancer. The intent of this study was to examine the use of registered FDG-PET/CT imaging to guide head and neck intensity modulated radiotherapy (IMRT) planning. METHODS: Twenty patients with squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx underwent FDG-PET and contrast-enhanced CT imaging of the head and neck before neck dissection surgery. Combined FDG-PET/CT images were created by use of a nonrigid image registration algorithm. All IMRT plans were theoretical and were not used for treatment. We prescribed 66 Gy in 30 fractions to FDG-avid CT abnormalities and nodal zones directly involved with disease, without prophylactic coverage of uninvolved neck levels. Matched CT-guided IMRT plans designed according to the specifications of Radiation Therapy Oncology Group (RTOG) H-0022 were available for comparison. We investigated the feasibility of FDG-PET/CT-directed IMRT dose escalation in five patients with FDG-avid disease located away from critical normal structures. After 66 Gy, FDG-avid disease with 0.5-cm margins was boosted in 220 cGy increments until dose-limiting criteria were reached. RESULTS: Elimination of prophylactic coverage to FDG-PET/CT-negative neck levels markedly reduced mean dose (Dmean) to the contralateral parotid gland (p < .001) and Dmean to the laryngeal cartilage (p = .001). No FDG-PET/CT-directed plan missed pathologically verified nodal disease. During the dose escalation exercise, we successfully increased the dose to 95% of the planning target volume (PTV95%) to a mean of 7490 cGy (range, 7153-8098 cGy). CONCLUSIONS: We demonstrate early proof of the principle that FDG-PET/CT-guided IMRT planning can selectively target and intensify treatment of head and neck disease while reducing critical normal tissue doses. Routine clinical use of such planning should not be engaged until the accuracy of FDG-PET/CT is fully validated. Future directions, including refinement of treatment to gross disease and radiologically uninvolved neck nodal levels, are discussed.     

Rapid superselective high-dose cisplatin infusion with concomitant radiotherapy for advanced head and neck cancer

PURPOSE: The purpose of this study was to evaluate the efficacy of rapid superselective high-dose cisplatin infusion with concomitant radiotherapy for previously untreated patients with advanced head and neck cancer. METHODS: Forty-three patients for whom surgery was contraindicated or who rejected radical surgery were given superselective intra-arterial infusions of cisplatin (100-120 mg/m2/week) with simultaneous intravenous infusion of thiosulfate to neutralize cisplatin toxicity and conventional extra-beam radiotherapy (65 Gy/26 f/6.5 weeks). RESULTS: Thirty-nine patients had stage IV disease, and the remaining four had stage III disease. During the median follow-up period of 21 months, the 3-year locoregional progression-free rates of all patients (n = 43) and patients with unresectable disease (n = 24) were 68.9% and 56.4%, respectively. In addition, the 3-year overall survival of all patients and patients with unresectable disease was 54.0% and 39.6%, respectively. Thirty-five patients (81.4%) experienced nonhematologic grade III to IV toxicity, including mucositis (n = 16), nausea/vomiting (n = 8), and neurologic signs (n = 2). No patient died as a result of treatment toxicity. There are 29 surviving patients without evidence of disease, all of whom are able to have oral intake without feeding-tube support. CONCLUSIONS: We confirmed the efficacy of superselective arterial infusion and concomitant radiotherapy, which can concentrate the attack of supradose cisplatin on locoregional disease. Even patients with unresectable disease can be cured. Further studies are needed to establish the indications, long-term outcome, and possible late side effects of this treatment.     

Histopathologic validation of the sentinel node concept in oral and oropharyngeal squamous cell carcinoma

BACKGROUND: In patients with head and neck squamous cell carcinoma (HNSCC), the presence of lymph node metastases is the most important prognosticator. Sentinel node (SN) biopsy has been shown to be an accurate staging technique for patients with breast cancer and melanoma and might also be suited for patients with HNSCC. This study was undertaken to determine whether the SN concept holds true for HNSCC and could be exploited for SN biopsy. METHODS: In 22 patients with T2 to T4 N0 oral or oropharyngeal squamous cell carcinoma (SCC) who were scheduled to undergo combined primary tumor excision and elective unilateral (n = 17) or bilateral (n = 5) neck dissection, SN identification was performed the day before surgery by use of lymphoscintigraphy after peritumoral injections of 99mTc-labeled colloidal albumin. After the neck dissection specimens were removed, all SNs, all other radioactive lymph nodes, and all nonradioactive lymph nodes were retrieved for histopathologic analysis, including serial sectioning at 250-microm intervals and immunohistochemical analysis (IHC). RESULTS: Overall, in 21 (78%) of 27 neck sides, an SN was identified by scintigraphy. Of the six neck sides in which SNs were not identified by scintigraphy, four were from three patients who underwent bilateral neck dissection. In another patient treated by bilateral neck dissection, the SN identified by scintigraphy could not be found in the specimen. In the remaining 20 neck dissection specimens, 23 SNs and 30 additional radioactive lymph nodes could be found. At histologic examination of the 20 neck specimens in which the SN was found, at least one SN was tumor positive in eight cases. In one neck specimen, a metastasis was detected in a nonradioactive lymph node, whereas the SN was tumor free, also at serial sectioning and IHC. In the remaining 11 neck sides in which the SN was tumor negative, none of the other radioactive (n = 13) and none of the nonradioactive (n = 279) lymph nodes contained tumor at histopathologic analysis, including serial sectioning and IHC. The sensitivity of the SN procedure for predicting lymph node metastases, therefore, was 89% (eight of nine neck specimens) when an SN was identified by scintigraphy and found in the specimen. The overall accuracy of the SN procedure for predicting the presence or absence of lymph node metastases in the neck was 95% (19 of 20 neck specimens). CONCLUSIONS: Our study seems to validate the SN hypothesis for oral and oropharyngeal cancer. The role of SN biopsy in the management of the N0 neck in such patients has yet to be established through prospective trials. SN identification (and thus biopsy) does not seem to be reliable in patients with tumors located in or close to the midline.     

Comparison of the Radiation Therapy Oncology Group recursive partitioning classification and Union Internationale Contre le Cancer TNM classification for patients with head and neck carcinoma

BACKGROUND: Prognostic models need to be tested in external validation studies to assess generalizability. Recursive partitioning analysis (RPA), a prognostic system based on the creation of a classification tree, has been proposed as a classification method in patients with head and neck carcinoma. The aim of this study was to compare the RPA and Union Internationale Contre le Cancer (UICC) TNM classification systems in patients with head and neck carcinoma treated consecutively in a single center. METHODS: A total of 2166 patients with carcinomas of the oral cavity, oropharynx, hypopharynx, and larynx was classified according to both the RPA and the TNM classification systems, and the results were compared. The endpoints considered were observed survival and survival free of locoregional tumor. The two methods of classification were evaluated objectively by use of measures of intrastage homogeneity (hazard consistency), interstage heterogeneity (hazard discrimination), predictive power (outcome prediction), and patient distribution between stages (balance). RESULTS: When the endpoint considered was observed survival, there were no clinically relevant differences between the two classifications. However, when the endpoint was locoregional control, the RPA system was sensitive to the type of treatment used, and it was not generalizable. CONCLUSIONS: To evaluate generalizability, new classification proposals need external validation studies that objectively measure the quality of the model. The performance of the RPA system was not reproducible in our cohort of patients when the endpoint evaluated was locoregional control.     

Prevalence of lymph nodes in the apex of level V: a plea against the necessity to dissect the apex of level V in mucosal head and neck cancer

BACKGROUND: We assessed the prevalence of histologically proven normal or invaded lymph nodes in the apex of level V. METHODS: Seventy neck dissections were performed in 41 patients with mucosal head and neck squamous cell carcinoma (SCC). Fifty-one neck dissections were performed in 30 previously untreated patients (group 1); 19 neck dissections were carried out in 11 patients previously irradiated (group 2). RESULTS: Pathologic analysis was unable to identify any lymph node in 70% of the apex specimens. In group 1, no lymph nodes were detected in 63%, whereas one or more noninvaded lymph nodes were present in 37%; in group 2, no lymph nodes were identified in 89%, whereas one or more normal lymph nodes were found in 11% (p = .03). Metastatic lymph nodes were never identified. CONCLUSIONS: The prevalence of lymph nodes in the apex was 30%. No invaded lymph nodes were identified. In addition to anatomic evidence, these results suggest that dissection of the apex is not necessary in mucosal head and neck SCC.     

带股方肌蒂骨瓣移植术治疗股骨头缺血性坏死一例

报道用带股方肌蒂骨瓣移植术成功地治疗一例11岁儿童左股骨头缺血性坏死,复习了手术方法;对本术式的适应症和并发症及有关血供进行了讨论。     

A method of head restraint in unanaesthetized cats by using frontal sinus

Two stainless steel bolts were implanted and fixed parallel in the frontal sinus of cats with dental acrylic and screws. When unanaesthetized, the head was fixed to a frame by securing the bolts to an acrylic plate. This arrangement provides a quick, rigid and safe fixation of the head without any signs of discomfort.