Transoral robotic surgical resection followed by randomization to low- or standard-dose IMRT in resectable p16+ locally advanced oropharynx cancer: A trial of the ECOG-ACRIN Cancer Research Group (E3311)

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Background: ECOG-ACRIN 3311 examines reduced postoperative therapy in patients with “intermediate risk” p16+ oropharynx cancer (OPC) undergoing primary transoral surgical management. We report the primary endpoint of 2-year progression free survival (PFS) for patients randomized to 50Gy vs 60Gy without chemotherapy. Methods: Between December 2013 and July 2017, 82 credentialed surgeons performed transoral resection (TOS) for 519 OPC patients (cT1-2 stage III/IV AJCC7 without matted neck nodes); post-operative management was determined by pathologically assessed risk. Among 353 eligible and treated patients, Arm A enrolled 10% (N=37) for clear margins, 0-1 nodes, no extranodal extension (ENE)), Arms B (50Gy, N=102) or C (60Gy, N=104) randomized 58%, for clear/close margins, 2-4 + nodes, or ENE ≤1mm, while Arm D (N=110, 60-66Gy plus weekly cisplatin, 40 mg/m2, positive margin with any T stage, >4 + nodes, or >1mm ENE) enrolled 31%. Arm D assignment was based on >1mm ENE (76%), > 4 nodes (27%), and/or positive margins (11%). Intermediate-risk patients were stratified by smoking history (>10 pk-yr). Of the 80 pts (15%) deemed ineligible, 28 had scans/labs not done per protocol, however treatment arm distribution for all patients mirrored that for the 353 pts eligible and treated. Results: Median follow-up was 31.8 months. 2 yr PFS for Arms A, B and C were 93.9% (90% CI=87.3%, 100%), 95.0% (90% CI=91.4%, 98.6%) and 95.9% (90% CI=92.6%, 99.3%) respectively, while Arm D was 90.5% (90% CI=85.9%, 95.3%). The regimen of TOS + low-dose radiation is considered worthy of further study, since the primary endpoint of the upper bound of the 90% CI (in the intermediate risk group) exceeding 85% was met. Of 17 progression events, 7 were locoregional. There were 10 distant recurrences: Arm A=1, Arm B=2, Arm C=4, Arm D=3. Grade III/IV treatment-related AE rates were 15%/2% during surgery, 13%/2% for Arm B and 25%/0% for Arm C. There were 2 treatment-related deaths (one surgical and one Arm D). Conclusions: Transoral resection of p16+ OPC is safe and results in good oncologic outcome, presenting a promising deintensification approach. For patients with low-risk disease, 2-yr PFS is favorable without post-operative therapy. For those with uninvolved surgical margins, <5 involved nodes, and minimal (<1mm) ENE, reduced dose postoperative RT without chemotherapy appears sufficient. Transoral surgery plus 50Gy should be compared to optimal non-surgical therapy in a phase III trial. Clinical trial information: NCT01898494 .

Extended pericranial flap and bone graft reconstruction in anterior skull base surgery

OBJECTIVES: The objectives of this study was to establish a rationale for repairing large anterior skull base defects with an extended pericranial flap and split calvarial bone graft; to define large anterior skull base defects as those spanning the anterior cranial measuring at least 3.0 × 4.0 cm; and to describe the surgical technique and compare it with alternative strategies.

STUDY DESIGN: Thirty-four patients underwent anterior craniofacial resection of anterior skull-based tumors of varying histology with reconstruction using an extended pericranial flap and split calvarial bone graft.

RESULTS: The survival of the pericranial flap and bone graft was maintained in 33 of 34 patients. There was 1 episode of postoperative cerebrospinal fluid leak, 1 episode of osteomyelitis of the bone graft and an epidural abscess, and 1 episode of asymptomatic pneumocephalus.

CONCLUSION: Split calvarial bone graft with an extended pericranial flap is an effective technique for reconstructing large anterior skull base defects.

Use of the LandmarXtrade mark Surgical Navigation System in Lateral Skull Base and Temporal Bone Surgery

Despite the widespread availability of surgical navigation devices, their use in lateral skull base and temporal bone surgery has been limited. Problems with current systems include difficulty of use and inadequate accuracy. We present a series of cases using the LandmarXtrade mark surgical navigation system as an adjunct for lateral skull base and temporal bone procedures. This infrared emitting diodes (IRED)-driven system has a post that carries the IREDs and bypasses the need to place the patient in a Mayfield head holder. This configuration allows greater mobility of the surgical field. Registration of the patient can include a combination of fiducial and anatomic landmarks that significantly increase accuracy compared to fiducial calibration alone. We introduced the use of the lateral process of the malleus as a landmark, thereby increasing accuracy within the temporal bone to a range of 0.9 to 1.5 mm. We used the system on encephaloceles, glomus tumors, meningiomas, and schwannomas, and revision surgery for chronic otitis media. It decreased operating time, allowed more effective use of "keyhole" approaches, and increased safety. As the availability and flexibility of these systems increase, their use should become the standard of care in revision temporal bone and lateral skull base procedures.

Nuclear receptor coregulators: judges, juries, and executioners of cellular regulation

In a little more than 10 years, nuclear receptor (NR) coregulators (coactivators and corepressors) have contributed to our present realization that a great level of sophistication exists in transcriptional regulation. Here, we discuss the implications of coregulators as versatile regulatory agents, influencing not only transcriptional initiation but also elongation, splicing, and translation. In addition to this, there is an increasing recognition that they also regulate a variety of biological processes outside of the nucleus. An important concept that we wish to emphasize is that coregulators are both targets and propagators of posttranslational modification (PTM) codes. This underlies a sophisticated epigenetic regulatory scheme from which a complex and dynamic mammalian phenotype emanates.

Absence of the steroid receptor coactivator-3 induces B-cell lymphoma

Steroid receptor coactivator 3 (SRC-3/ACTR/AIB-1/pCIP/RAC3/TRAM-1) is a member of the p160 family of nuclear receptor coactivators that plays an important role in mammary gland growth, development, and tumorigenesis. We show that deletion of SRC-3 gene decreases platelet and increases lymphocytes numbers, leading to the development of malignant B-cell lymphomas upon aging. The expansion of the lymphoid lineage in SRC-3(-/-) mice is cell autonomous, correlates with an induction of proliferative and antiapoptotic genes secondary to constitutive NF-kappaB activation, and can be reversed by restoration of SRC-3 expression. NF-kappaB activation is explained by the degradation of IkappaB, consequent to increases in free IkappaB kinase, which is no longer inhibited by SRC-3. These results demonstrate that SRC-3 regulates lymphopoiesis and in combination with previous studies indicate that SRC-3 has vastly diverging effects on cell proliferation depending on the cellular context, ranging from proliferative and tumorigenic (breast) to antiproliferative (lymphoid cells) effects.

Maintenance of hemostasis in transoral robotic surgery

BACKGROUND

The last decade has seen a tremendous growth in the field of robotic surgery with an increasing number of cardiac and urologic procedures performed each year. Several attributes of this technology may offer advantages to laryngeal and pharyngeal surgery in that it allows for exceptional visualization of the operative field, precise handling of soft tissues, and multiplanar transection of tissues. One potential limitation is the management of bleeding in transoral pharyngeal and laryngeal surgery, which is critical to prevent both intravascular volume loss and aspiration.

OBJECTIVES

To demonstrate methods for management of bleeding in the surgical field during transoral robotic surgery (TORS).

METHODS

We developed a canine robotic surgery model for the evaluation of the ability to control bleeding in laryngeal and pharyngeal procedures using the daVinci surgical robot (Intuitive Surgical, Inc., Sunnyvale, Calif., USA). Both large- and small-vessel hemostasis was obtained with both robotically controlled monopolar and bipolar cautery and with robotically controlled small hemoclips. Additionally, manually controlled large hemoclips were applied by an assistant surgeon viewing on a video monitor for management of large arterial vessels. Suction was performed with both flexible suction catheters controlled by the robotic arms and with manually controlled conventional suction catheters. Data were collected with still and video photography.

RESULTS

The lingual artery as well as small arteries and veins were easily controlled and there were no difficulties with maintenance of hemostasis.

CONCLUSIONS

Effective hemostasis with control of both large and small vessels can be obtained using both surgical hemoclips and electrocautery during TORS in a canine model.

Transoral robotic surgery: supraglottic laryngectomy in a canine model

OBJECTIVES/HYPOTHESIS

To develop a technique for computer enhanced robotic transoral supraglottic partial laryngectomy in the canine model.

STUDY DESIGN

Surgical procedure on the larynx in a canine model with a commercially available surgical robot.

METHODS

With use of the da Vinci Surgical Robot (Intuitive Surgical, Inc., Sunnyvale, CA), the supraglottic partial laryngectomy was performed on a mongrel dog that had been orotracheally intubated using general anesthesia. The videoscope and the 8 mm end-effectors of the robotic system were introduced through three ports, transorally. The surgical procedure was performed remotely from the robotic system console. The procedure was documented with still and video photography.

RESULTS

Supraglottic partial laryngectomy was successfully performed using the da Vinci Surgical Robot, with 8 mm instrumentation. The robotic system allowed for celerity and accuracy secondary to findings specific to the surgical approach, including excellent hemostasis, superb visualization of the operative field with expeditious identification of laryngeal submucosal soft tissue and skeletal landmarks, and multiplanar transection of tissues. In addition, the use of the robotic system also was found to have technical advantages inherent in robotic surgery, including the use of "wristed" instrumentation, tremor abolition, motion scaling, and three-dimensional vision.

CONCLUSIONS

The da Vinci Surgical Robot allowed for successful robotic transoral supraglottic partial laryngectomy in the canine model.

Splicing potentiation by growth factor signals via estrogen receptor phosphorylation

Mitogen-activated protein kinase-mediated growth factor signals are known to augment the ligand-induced transactivation function of nuclear estrogen receptor alpha (ERalpha) through phosphorylation of Ser-118 within the ERalpha N-terminal transactivation (activation function-1) domain. We identified the spliceosome component splicing factor (SF)3a p120 as a coactivator specific for human ERalpha (hERalpha) activation function-1 that physically associated with ERalpha dependent on the phosphorylation state of Ser-118. SF3a p120 potentiated hERalpha-mediated RNA splicing, and notably, the potentiation of RNA splicing by SF3a p120 depended on hER Ser-118 phosphorylation. Thus, our findings suggest a mechanism by which growth factor signaling can regulate gene expression through the modulation of RNA splicing efficiency via phosphorylation of sequence-specific activators, after association between such activators and the spliceosome.

Robotic Microlaryngeal Surgery: A Technical Feasibility Study Using the daVinci Surgical Robot and an Airway Mannequin

OBJECTIVES/HYPOTHESIS

The trend toward minimally invasive surgery has led to the development and mastery of endoscopic and laparoscopic surgical techniques. These minimally invasive approaches, which only two decades ago were either novel or experimental, are now mainstream. More recently, robot-assisted surgery has evolved as an adjunct to open and endoscopic techniques. Surgical robots are now approved by the United States Food and Drug Administration for a variety of thoracic and abdominal/pelvic surgical procedures. The purpose of this study is to demonstrate the technical feasibility of robot-assisted microlaryngeal surgery.

STUDY DESIGN

Experimental surgical manipulation of the larynx in an airway mannequin with a surgical robot.

METHODS

A variety of laryngoscopes and mouthgags, coupled with the daVinci Surgical Robot's (Intuitive Surgical, Sunnyvale, CA) 0-degree and 30-degree, two-dimensional and three-dimensional endoscopes, were utilized to optimize visualization of the larynx in an airway mannequin. Five millimeter and 8 mm microinstruments compatible with the daVinci robot were utilized to manipulate different elements of the larynx. Experiments were recorded with both still and video photography.

RESULTS

The endoscope and robotic arms of the daVinci robot are well suited to airway surgery.

CONCLUSIONS

Robot-assisted laryngeal surgery can be performed with currently available technology. The potential for fine manipulation of tissues, increased freedom of instrument movement, and endolaryngeal suturing may increase the precision of endoscopic laryngeal microsurgery and offers the potential to increase the variety of laryngeal procedures that can be performed endoscopically.

Regulation of male sexual behavior by progesterone receptor, sexual experience, and androgen

Recent studies have demonstrated that physiological doses of progesterone may facilitate the androgen-dependent display of male sexual behavior in laboratory rats and three species of lizard. We used mice with a targeted disruption of the progesterone receptor to investigate whether such interactions exist in male mice and whether they may be modified by sexual experience. We found that naive intact male progesterone receptor knockout (PRKO) mice exhibit reduced mount frequencies compared to wild-type (WT) mice. Also unlike WT mice, sexually experienced PRKO males show profound losses in many measures of sexual behavior following castration. In a second experiment, we tested whether male mice heterozygous for a null mutation at the progesterone receptor locus were responsive to testosterone and progesterone treatment. We found that heterozygous males showed a reduced response to testosterone. The data are consistent with experiments indicating that the progesterone receptor is able to facilitate male-typical sex behaviors in other species and suggest novel mechanisms underlying the interaction of androgens and experience.