Late free flap failure in head and neck reconstruction: A systematic review.

Our objectives were to review all reported cases of late flap failure in head and neck surgery and describe any relevant patterns. We conducted a systematic review of all published cases of free flap failure after postoperative day 7 in head and neck surgery from January 1990 to January 2018. Data were collected with respect to flap type, site of reconstruction, reason for failure, and time to failure. A total of 45 cases of late free flap failure in the head and neck were identified. Among the 34 cases in which the necessary data were available for analysis, 50% of late failures occurred between postoperative day 7 and 14. Common reasons for failure were abscess and vascular compromise. We conclude that most late flap failures occur in the second postoperative week. In patients with risk factors for flap failure, close monitoring for up to 14 days after surgery could detect flap compromise before the flap is lost.

Malignant Struma ovarii in a 30-year old nulliparous patient.

BACKGROUND: Struma ovarii is a rare monodermal germ cell tumor where the ovary is comprised of at least half thyroid tissue. This phenomenon may indicate an embryological origin. CASE PRESENTATION: A 30-year old nulliparous woman presented with acute right lower quadrant pain and underwent laparoscopic right salpingo-oophorectomy. The excised ovarian mass showed evidence of struma-derived papillary thyroid carcinoma. Ultrasound of the thyroid showed mild enlargement with two solid nodules. A fine needle aspirate of a thyroid nodule was positive for malignancy and a total thyroidectomy was performed. Microscopic features of the thyroid were consistent with papillary thyroid carcinoma. The two tumours were considered as synchronous independent primaries based on their histological presentation. CONCLUSIONS: We believe that aggressive surgical management followed by radioiodine therapy is best to reduce recurrence risk and optimize survival. The broad scope of interventions needed to treat malignant struma ovarii require a strong interdisciplinary team.

The Hippo component YAP localizes in the nucleus of human papilloma virus positive oropharyngeal squamous cell carcinoma.

BACKGROUND: HPV infection causes cervical cancer, mediated in part by the degradation of Scribble via the HPV E6 oncoprotein. Recently, Scribble has been shown to be an important regulator of the Hippo signaling cascade. Deregulation of the Hippo pathway induces an abnormal cellular transformation, epithelial to mesenchymal transition, which promotes oncogenic progression. Given the recent rise in oropharyngeal HPV squamous cell carcinoma we sought to determine if Hippo signaling components are implicated in oropharyngeal squamous cell carcinoma. METHODS: Molecular and cellular techniques including immunoprecipiations, Western blotting and immunocytochemistry were used to identify the key Hippo pathway effector Yes-Associated Protein (YAP)1. Oropharyngeal tissue was collected from CO2 laser resections, and probed with YAP1 antibody in tumor and pre-malignant regions of HPV positive OPSCC tissue. RESULTS: This study reveals that the Scribble binding protein Nitric Oxide Synthase 1 Adaptor Protein (NOS1AP) forms a complex with YAP. Further, the NOS1APa and NOS1APc isoforms show differential association with activated and non-activated YAP, and impact cellular proliferation. Consistent with deregulated Hippo signaling in OPSCC HPV tumors, we see a delocalization of Scribble and increased nuclear accumulation of YAP1 in an HPV-positive OPSCC. CONCLUSION: Our preliminary data indicates that NOS1AP isoforms differentially associate with YAP1, which, together with our previous findings, predicts that loss of YAP1 enhances cellular transformation. Moreover, YAP1 is highly accumulated in the nucleus of HPV-positive OPSCC, implying that Hippo signaling and possibly NOS1AP expression are de-regulated in OPSCC. Further studies will help determine if NOS1AP isoforms, Scribble and Hippo components will be useful biomarkers in OPSCC tumor biology.

Multifocal Papillary Thyroid Cancer Increases the Risk of Central Lymph Node Metastasis.

BACKGROUND: Papillary thyroid cancer (PTC) is the most common thyroid malignancy, with a strong predilection for lymph node metastasis, most commonly to the central neck compartment (level VI). Few studies have evaluated lymph node metastasis in multifocal PTC, and the role of level VI dissection in the management of PTC remains controversial. This retrospective analysis evaluated the rate of level VI lymph node positivity in multifocal PTC, as compared with unifocal disease, in order to inform surgical decision making better. METHODS: Patients with PTC who underwent total or hemi-thyroidectomy plus level VI lymph node dissection at the authors' institution between January 2008 and June 2014 were included (N=227). The number and laterality of PTC foci, lymphovascular invasion (LVI), extrathyroidal extension (ETE), and positive/total number of level VI lymph nodes were recorded. Fisher's exact test was used to determine univariate associations, and multivariate analysis was done by logistical regression. RESULTS: There was an association between the number of PTC foci and level VI node positivity (p<0.001), with an odds ratio (OR) of 2.355 in patients with three or more tumor foci (p=0.026). The OR for central neck metastasis was 1.088 with each additional focus of PTC (p=0.018). The risk of level VI node positivity in the presence of one or two foci was only 19%, with no appreciable difference between one and two foci. This risk increased in the presence of between three and nine foci (38%), and 10 or more foci (88%). Level VI node positivity was associated with ETE (p<0.001), LVI (p<0.001), and size of the largest focus (p<0.001). There was no association between level VI lymph node positivity and male sex (p=0.089), bilaterality (p=0.276), or age (p=0.076). CONCLUSIONS: There is a significant association between multifocal PTC and level VI lymph node positivity, increasing proportionally with the number of foci. These findings recognize multifocality as a sign of tumor aggressiveness, as evidenced by a higher propensity for lymph node metastasis.

Preoperative headband assessment for semi-implantable bone conduction hearing devices in conductive hearing loss: is it useful or misleading?

OBJECTIVE: To establish whether preoperative assessment using a conventional, percutaneous bone conducting implant (pBCI) processor on a headband accurately represents postoperative performance of a semi-implantable BCI (siBCI). STUDY DESIGN: Retrospective case series. SETTING: Tertiary otology unit. PATIENTS: Five patients with chronic otitis media (implanted unilaterally) and one with bilateral congenital ossicular fixation (implanted bilaterally). INTERVENTION(S): Semi-implantable bone conduction hearing implant. MAIN OUTCOME MEASURE(S): Functional hearing gain; preoperative (headband) versus postoperative (aided) speech discrimination; unaided bone conduction (BC) versus postoperative (aided) soundfield threshold. RESULTS: Significant functional gain was seen at all frequencies (one-tailed t test p G 0.01; n = 7). There was a 50 dB improvement in median speech reception threshold (SRT) from 70 dB unaided to 20 dB aided. Compared to the preoperative BC, aided siBCI thresholds were worse at 0.5 kHz, but at frequencies from 1 to 6 kHz, the siBCI closely matched the bone curve ( p G 0.01). The siBCI performed better than both pBCI processors on a headband at 3 to 4 kHz, except 1 kHz ( p G 0.01). CONCLUSIONS: BC thresholds may be a better indicator of implant performance than headband assessment. Candidacy assessment for siBCI implantation that relies on headband testing with pBCI processors should be interpreted with caution because the headband may under-represent the implanted device. This seems to be especially true at 3 kHz and above and may make it difficult for surgeons to conduct accurate informed consent discussions with patients about the realistic anticipated outcomes and benefits of the procedure.

Surgical management of primary hyperparathyroidism in Canada.

Primary hyperparathyroisim is a relatively common condition, for which the standard treatment is surgical excision of one or more of the parathyroid glands. Primary hyperparathyroidism can be due to a single adenoma or multiple gland hyperplasia. In recent decades localizing imaging has improved and there has been a shift away from multiple gland exploration toward a single gland excision. There are, however, no practice guidelines regarding an optimal approach to this condition. This study shows that there is a high degree of variation in practices across Canada and a large amount of uncertainty in the approach to primary hyperparathyroidism.

Rates of thyroid malignancy by FNA diagnostic category.

BACKGROUND: Fine needle aspiration (FNA) of thyroid nodules is a cornerstone of surgical decision making in thyroid cancer. The most widely utilized system for reporting thyroid FNA results is the Bethesda System, which includes predicted malignancy rates for each FNA category. To date there have been few studies to determine whether these predictions are widely applicable. METHODS: All thyroid FNA results at the Queen Elizabeth II Health Science Centre from 2006-2010 were included in this study. The results were tabulated by FNA category and the health records were reviewed to determine whether the patient went on to have surgery and the result of surgical histopathology. Rates of malignancy were calculated and compared to published values. RESULTS: A total of 1491 thyroid FNAs were included in the study, representing 1117 individual patients with available health records. The majority of these FNAs were Benign, but the proportion of Unsatisfactory FNAs was higher than predicted while Malignant and Suspicious for Malignancy were lower than predicted. Surgery was performed on 388 patients and 110 were positive for malignancy (28%). The malignancy rate for each FNA category was higher than predicted based on literature values. CONCLUSIONS: The proportions of FNA diagnoses and the rates of malignancy for each FNA category at our institution were not consistent with predicted values. It is important for clinicians to base their surgical recommendations on institution specific malignancy rates, not solely on literature values.

Impact of arteriogenesis in plastic surgery: choke vessel growth proceeds via arteriogenic mechanisms in the rat dorsal island skin flap.

OBJECTIVE: We examined the molecular mediators of postoperative choke-vessel growth. Our focus was the possible overlap between choke-vessel growth and arteriogenesis. METHODS: A rat perforator flap model, encompassing four vascular territories, was used. Flaps were surgically elevated, re-inset, and allowed to survive for one, three, five, or seven days. Tissue samples for Western and histological analyses were collected from the choke zone along the dorsal midline. Tissue from territories linked by the choke zone was analyzed to distinguish between global and local effects. The proteins examined included CD11b, ICAM-1, and MMP-2, three markers associated with arteriogenesis, as well as Hsp70 and vascular endothelial growth factor, markers of physiological stress and hypoxia/ischemia. RESULTS: Arteriogenesis markers, as shown by Western analysis, increased at three and five days after flap elevation, and the increase was localized by immunohistochemistry to the growing arteries and veins. The marker of physiological stress increased at Days 5 and 7. The hypoxia-ischemia marker did not increase in the choke zone. CONCLUSIONS: The growth of choke arteries and veins proceeds in an inflammatory environment that resembles arteriogenesis. Ischemia did not appear to play a role in choke-vessel changes.