Squamous cell carcinoma of unknown primary of the head and neck: Favorable prognostic factors comparable to those in oropharyngeal cancer.

BACKGROUND: Treatment for squamous cell carcinoma (SCC) of unknown primary consists of radiotherapy (RT) +/- chemotherapy or neck dissection +/- adjuvant RT/chemoradiotherapy (CRT). We compared these strategies and identified prognostic factors. METHODS: From 1993 to 2015, 75 patients with SCC of unknown primary had RT-based or surgery-based treatment. Primary endpoints were overall survival (OS) and disease-free survival (DFS). Event-time distributions were estimated using the Kaplan-Meier method. RESULTS: Five-year OS and DFS for RT-based and surgery-based treatments were similar (OS 73% vs 68%, respectively; DFS 65% vs 64%, respectively). Among 38 patients with p16 data, 76% were p16 positive and showed improved 5-year DFS (90% vs 33%; P = .001) and OS (96% vs 33%; P < .001). Smoking history ≤10 pack-years conferred better 5-year DFS (88% vs 49%; P < .001) and OS (91% vs 59%; P < .001). CONCLUSION: RT-based and surgery-based treatments produced similar outcomes. Patients with p16-positive disease with ≤10 pack-years of smoking history and limited nodal stage constitute a "low-risk" group in SCC of unknown primary similar to that in oropharyngeal cancer.

Oral human papillomavirus infection in men who have sex with men with anal squamous intraepithelial lesions.

BACKGROUND: Little is known about the association between oral and anogenital human papillomavirus (HPV) infections. METHODS: Oral and anal samples from 66 men who have sex with men with a history of HPV-related anogenital squamous intraepithelial lesions were analyzed using polymerase chain reaction (PCR), and typed for 38 HPV types. RESULTS: Prevalence of oral HPV infection was 30%, versus 82% for anal infection. Prevalence of oral and anal high-risk HPV infection was 11% and 64%, respectively. Concurrent oral-anal any-type HPV infection was found in 26% of participants, whereas concordant type-specific HPV prevalence was 5%. In multivariate analysis, number of partners from whom the participant received oral-penile sex and number of partners on whom the participant performed oral-penile sex were associated with oral HPV infection. CONCLUSION: Oral HPV prevalence in this cohort is high, however, concordant type-specific oral-anal HPV infection was rare. Increased risk of oral HPV infection was associated with oral-penile sex. © 2015 Wiley Periodicals, Inc. Head Neck 38: E399-E405, 2016.

A spheroid weighted-axis converter of vestibular schwannoma size: maximum diameter and cisternal volume.

OBJECTIVES: To evaluate spheroid models of vestibular schwannoma (VS) size for bidirectional conversion of maximum diameter in the cistern and 3-dimensional volume. STUDY DESIGN: Methodological study. SETTING: Academic tertiary referral center. SUBJECTS AND METHODS: Magnetic resonance imaging studies from 91 patients with VS from 2003 to 2011 were analyzed. Linear measurements defining meatal and cisternal components were extracted. Geometrically based conformal models of tumor volume were compared with measured tumor volume using a semiautomated computerized tracing method. Models were inverted to predict maximum axial cisternal length at the level of the internal auditory canal (IAC). RESULTS: A spheroid-weighted axis converter (SWC) of VS size was identified by minimizing input measurement parameters while maximizing output prediction performance. Computation steps of tumor volumes were (1) meatal-measure tumor lengths along the IAC and at the porus acusticus and take the average of a cone and cylinder and (2) cisternal-measure maximum tumor length in the axial IAC plane, use the median major:minor axis ratio of 1.26:1 to estimate minor axis length, take the geometric mean of axial dimensions to estimate axis length in the coronal plane, and apply input lengths to a spheroid. Performance error of this SWC had interquartile ranges of 33% for volume and 2 to 3 mm for maximum cisternal length. CONCLUSION: Reporting variability of VS tumor size has made it difficult to reconcile outcomes studies. We propose an accessible tool for bidirectional conversion of volumetric and linear indices of tumor size to unlock potential for meta-analyses of disparate data sets.

Computed tomography and magnetic resonance imaging characteristics of acute invasive fungal sinusitis.

OBJECTIVE: To determine radiographic findings on computed tomography (CT) and magnetic resonance imaging (MRI) predictive of acute fulminant invasive fungal sinusitis (AFIFS) in an immunocompromised patient population. DESIGN: Retrospective case-control study. SETTING: Tertiary referral hospital. PATIENTS: Cases were 17 immunocompromised patients with confirmed AFIFS after surgical debridement or biopsy. Controls were 6 immunocompromised patients histopathologically negative for AFIFS after surgical debridement or biopsy. MAIN OUTCOME MEASURES: Computed tomographic and MRI scans were independently reviewed by 2 neuroradiologists to identify imaging characteristics predictive of AFIFS. Operative reports and histopathologic, microbiologic, and survival data were reviewed. RESULTS: No significant differences with regard to baseline characteristics between the 2 groups were identified. There was moderate or substantial agreement (κ = 0.40-0.77) between the 2 radiologists for all imaging parameters except MRI loss of contrast enhancement (κ = 0.16). Magnetic resonance imaging was more sensitive than CT for the diagnosis of AFIFS (sensitivity 85% and 86% for both reviewers compared with 57% and 69%). Extrasinus invasion with MRI was the most sensitive individual parameter (87% and 100%). Magnetic resonance imaging and CT had similar specificities, and perisinus invasion was the most specific individual parameter (83% and 83% for MRI compared with 81% and 83% for CT). The positive predictive values were high for both imaging modalities (93% and 94% for MRI compared with 89% and 93% for CT). The negative predictive values were lower for both modalities and varied more between reviewers (71% and 100% for MRI compared with 45% and 67% for CT). CONCLUSIONS: Magnetic resonance imaging is more sensitive for detecting early changes of AFIFS than CT. Both imaging modalities have similar specificities. Perisinus invasion with MRI was the most sensitive and specific single parameter evaluated.

Vascular malformation masquerading as sialolithiasis and parotid obstruction: a case report and review of the literature.

INTRODUCTION: Salivary gland obstruction caused by sialolithiasis or duct stricture is one of the more common causes of non-infectious unilateral facial selling. Vascular malformations of the head and neck are less common but may present with intermittent facial swelling. Phleboliths can be found in venous malformations of nearly all adult patients and are a key diagnostic imaging finding. The clinical and radiographic appearance of phleboliths may resemble sialolithiasis, making the diagnosis more difficult. We present a case of intermittent unilateral facial swelling cause by a venous malformation involving the buccal space where the phleboliths were initially misdiagnosed as parotid sialolithiasis. STUDY DESIGN: Illustrative case report and literature review. METHODS: A 48 year-old woman presented to our office with 9 months of intermittent left facial swelling. On bimanual examination, multiple small firm nodules were palpated in the left cheek. A computed tomography (CT) scan demonstrated multiple oval-shaped radiopaque lesions in the buccal space, initially interpreted as sialoliths. Magnetic resonance imaging (MRI) was obtained, confirming the diagnosis of venous malformation with phleboliths. Sialendoscopy revealed a normal appearing parotid duct system without stricture or sialolithiasis. Ultrasound revealed a buccal space vascular lesion surrounding the distal Stensen's duct. RESULTS: Currently, the patient is being observed and is clinically stable. Illustrative CT scan and MRI images are presented. A literature review shows that vascular malformations mimicking salivary gland obstruction are rare. CONCLUSIONS: While unilateral facial swelling is commonly due to parotid sialoliths or parotid duct stenosis, other less common causes including vascular malformation should be considered. Phleboliths and sialoliths may appear similar on ono-contrast CT scan. Ultrasound, MRI, and sialendoscopy may be helpful in determining the etiology.

Ambulation in simulated fractional gravity using lower body positive pressure: cardiovascular safety and gait analyses.

The purpose of this study is to assess cardiovascular responses to lower body positive pressure (LBPP) and to examine the effects of LBPP unloading on gait mechanics during treadmill ambulation. We hypothesized that LBPP allows comfortable unloading of the body with minimal impact on the cardiovascular system and gait parameters. Fifteen healthy male and female subjects (22-55 yr) volunteered for the study. Nine underwent noninvasive cardiovascular studies while standing and ambulating upright in LBPP, and six completed a gait analysis protocol. During stance, heart rate decreased significantly from 83 +/- 3 beats/min in ambient pressure to 73 +/- 3 beats/min at 50 mmHg LBPP (P < 0.05). During ambulation in LBPP at 3 mph (1.34 m/s), heart rate decreased significantly from 99 +/- 4 beats/min in ambient pressure to 84 +/- 2 beats/min at 50 mmHg LBPP (P < 0.009). Blood pressure, brain oxygenation, blood flow velocity through the middle cerebral artery, and head skin microvascular blood flow did not change significantly with LBPP. As allowed by LBPP, ambulating at 60 and 20% body weight decreased ground reaction force (P < 0.05), whereas knee and ankle sagittal ranges of motion remained unaffected. In conclusion, ambulating in LBPP has no adverse impact on the systemic and head cardiovascular parameters while producing significant unweighting and minimal alterations in gait kinematics. Therefore, ambulating within LBPP is potentially a new and safe rehabilitation tool for patients to reduce loads on lower body musculoskeletal structures while preserving gait mechanics.

Space exercise and Earth benefits.

The detrimental impact of long duration space flight on physiological systems necessitates the development of exercise countermeasures to protect work capabilities in gravity fields of Earth, Moon and Mars. The respective rates of physiological deconditioning for different organ systems during space flight has been described as a result of data collected during and after missions on the Space Shuttle, International Space Station, Mir, and bed rest studies on Earth. An integrated countermeasure that simulates the body's hydrostatic pressure gradient, provides mechanical stress to the bones and muscles, and stimulates the neurovestibular system may be critical for maintaining health and well being of crew during long-duration space travel, such as a mission to Mars. Here we review the results of our studies to date of an integrated exercise countermeasure for space flight, lower body negative pressure (LBNP) treadmill exercise, and potential benefits of its application to athletic training on Earth. Additionally, we review the benefits of Lower Body Positive Pressure (LBPP) exercise for rehabilitation of postoperative patients. Presented first are preliminary data from a 30-day bed rest study evaluating the efficacy of LBNP exercise as an integrated exercise countermeasure for the deconditioning effects of microgravity. Next, we review upright LBNP exercise as a training modality for athletes by evaluating effects on the cardiovascular system and gait mechanics. Finally, LBPP exercise as a rehabilitation device is examined with reference to gait mechanics and safety in two groups of postoperative patients.

Lower body positive-pressure exercise after knee surgery.

Lower body positive pressure allows unloading of the lower extremities during exercise in a pressurized treadmill chamber. This study assessed the preliminary feasibility of lower body positive pressure exercise as a rehabilitation technique by examining its effects on gait mechanics and pain, postoperatively. Fifteen patients who had arthroscopic meniscectomy or anterior cruciate ligament reconstruction participated in this study. Patients exercised for 5 minutes at 2.0 mph under three body weight conditions (normal body weight, 60% body weight, and 20% body weight) in random order. Bilateral ground reaction force, electromyographs, and dynamic knee range of motion were collected, and pain was assessed using a visual analog scale. Ground reaction forces for surgically treated and contralateral extremities were reduced 42% and 79% from normal body weight conditions when ambulating at 60% and 20% body weight, respectively. After meniscectomy, ambulatory knee range of motion decreased only at 20% body weight (37 degrees), compared with normal body weight conditions (49 degrees). Peak electromyographic activity of the biceps was maintained at all body weight conditions, whereas that of the vastus medialis was reduced at 20% body weight. Pain relief was significant with lower body positive pressure ambulation after anterior cruciate ligament reconstruction. This study showed that lower body positive pressure exercise is effective at reducing ground reaction forces, while safely facilitating gait postoperatively.

Ischemic-preconditioning does not prevent neuromuscular dysfunction after ischemia-reperfusion injury.

The primary purpose of this study was to evaluate ischemic-preconditioning (IPC) as a means of improving tolerance to ischemia-reperfusion (IR) stress on neuromuscular function. A secondary objective was to isolate the area of injury within the neuromuscular unit responsible for contractile dysfunction after IR injury. Twenty-eight male rabbits were randomly assigned to four groups (sham, IPC only, sustained ischemia only, IPC and sustained ischemia). The IPC protocol consisted of three cycles of 10 min of tourniquet-induced ischemia (125 mmHg) followed by 10 min of reperfusion. Sustained ischemia was induced by 350 mmHg external compression for 2 h. Peak tetanic tension of the tibialis anterior (TA) muscle was evaluated 48 h after the tourniquet protocol by both peroneal nerve and direct muscle stimulation, with and without pharmacologic neuromuscular junction blockade. Animals subjected to combined IPC and sustained ischemia had an equivalent loss of contractile force to those undergoing sustained ischemia alone. Two hours of tourniquet-induced ischemia resulted in marked dysfunction of the TA neuromuscular unit when evaluated by peroneal nerve stimulation (p < 0.0001). Isolation of the TA muscle from the peroneal nerve with direct muscle stimulation and neuromuscular junction blockade preserved muscle function after 3 h of ischemia. In our model, these results clearly demonstrate that IPC provides no significant protective effect from IR injury to either nerve or muscle function in our model. In addition, nerve or neuromuscular junction injury, rather than muscle damage, is identified as primarily responsible for IR-related muscle dysfunction.

Intramuscular and blood pressures in legs positioned in the hemilithotomy position : clarification of risk factors for well-leg acute compartment syndrome.

BACKGROUND: Acute compartment syndrome has been widely reported in legs positioned in the lithotomy position for prolonged general surgical, urologic, and gynecologic procedures. The orthopaedic literature also contains reports of this complication in legs positioned on a fracture table in the hemilithotomy position. The purpose of this study was to identify the risk factors for development of acute compartment syndrome resulting from this type of leg positioning. METHODS: Eight healthy volunteers were positioned on a fracture table. Intramuscular pressures were continuously measured with a slit catheter in all four compartments of the left leg with the subject supine, in the hemilithotomy position with the calf supported, and in the hemilithotomy position with the heel supported but the calf free. Blood pressure was measured intermittently with use of automated pressure cuffs. RESULTS: Changing from the supine to the calf-supported position significantly increased the intramuscular pressure in the anterior compartment (from 11.6 to 19.4 mm Hg) and in the lateral compartment (from 13.0 to 25.8 mm Hg). Changing from the calf-supported to the heel-supported position significantly decreased intramuscular pressure in the anterior, lateral, and posterior compartments (to 2.8, 3.4, and 1.9 mm Hg, respectively). The mean diastolic blood pressure in the ankle averaged 63.9 mm Hg in the supine position, which significantly decreased to 34.6 mm Hg in the calf-supported position. Changing to the heel-supported position had no significant effect on the diastolic blood pressure in the ankle (mean, 32.8 mm Hg). The mean difference between intramuscular pressure and diastolic blood pressure in the supine position was approximately 50 mm Hg in each of the four compartments. This mean difference significantly decreased to <20 mm Hg in the calf-supported position and then, when the leg was moved into the heel-supported position, significantly increased to approximately 30 mm Hg in all compartments. CONCLUSIONS: The combination of increased intramuscular pressure due to external compression from the calf support and decreased perfusion pressure due to the elevated position causes a significant decrease in the difference between the diastolic blood pressure and the intramuscular pressure when the leg is placed in the hemilithotomy position in a well-leg holder on a fracture table. Combined with a prolonged surgical time, this position may cause an acute compartment syndrome of the well leg. Leaving the calf free, instead of using a standard well-leg holder, increases the difference between the diastolic blood pressure and the intramuscular pressure and may decrease the risk of acute compartment syndrome.