Effects of drill speed on heat production and the rate and quality of bone formation in dental implant osteotomies. Part I: Relationship between drill speed and heat production

The amount of heat produced by dental implant osteotomy (receptor site) preparation at different speeds and the effects of heat production on the prognosis of implant treatment are controversial. In Part I of this two-part study, heat production was measured in vivo during osteotomy preparation at low (maximum 2,000 rpm), intermediate (maximum 30,000 rpm), and high (maximum 400,000 rpm) speeds in the rabbit tibia, and an inverse relationship was observed between drill speed and heat production. For the measurement of heat production (Part I), a thermocouple probe was inserted into a prepared receptor site in the anteromedial aspect of the tibial metaphysis. Temperature was recorded while an osteotomy was drilled 1 mm from the thermocouple receptor site. Distilled water was used as coolant in conjunction with all drilling, and all osteotomies were prepared by a single researcher to eliminate the variable of interoperator difference in technique. An inverse relationship was observed between drill speed and heat production. An analysis of variance indicated significant differences in heat production among the three drilling speeds (P < 0.05). The results of Part 1 of this study indicate that for the configuration and material of bur used, the high-speed range minimizes heat production.

Abstract P3-04-08: Expression of hormone-responsive genes in benign breast tissue varies with menstrual cycle phase and menopausal status

Background: The expression of many genes is known to be regulated by ambient hormone levels. In a preliminary study of random fine-needle aspirate (rFNA) samples from benign breast tissue, we found several genes that were highly correlated with the serum levels of progesterone (P4) and estradiol (E2). We now present data to further validate these genes as markers of menstrual cycle phase (MCP) and menopausal status (MPS) in benign breast tissue which may allow retrospective classification of archived breast samples with respect to MCP and MPS at the time of sampling.

Methods: 240 rFNA samples from healthy women with recorded hormonal data at the time of sampling were analyzed. We divided these subjects by menstrual cycle phase (MCP) and menopausal status (MPS): 41 early follicular: (low circulating E2 and P4); 48 mid-cycle (high E2 and low P4); 31 luteal (moderate E2 and high P4). 120 post-menopausal (low E2 and low P4). 100 ng of RNA from rFNA samples of the breast was reverse transcribed. Amplicons of interest were linearly amplified to 14 cycles for 35 genes related to hormone responsiveness. qPCR reactions were carried out using the TaqMan OpenArray (Applied Biosystems). For each gene of interest, expression levels were normalized to the average expression of GAPDH. Gene expression difference between groups were conducted using the Mann-Whitney Test. P-values from gene expression difference were adjusted via the Benjamini-Hochberg (1995) approach.

Results: The mean value of TNFSF11 expression level was 13.19 fold higher in luteal phase subjects than in post-menopausal subjects (p = 0.0003) where there was also the biggest difference of serum P4 level between groups. The expression of DIO2 and MYBPC1 was also significantly higher in luteal phase group than in the post-menopausal group (p = 0.005, p = 0.02, respectively). These 3 genes also demonstrated a higher expression pattern in luteal phase than mid-cycle and follicular phase but analysis is still ongoing. All comparisons between these groups will be presented at the meeting.

Conclusion: The expression levels of TNFSF11, DIO2 and MYBPC1 vary with MCP and MPS. These hormone-responsive genes are candidate MCP classifiers which could be applied to archived breast samples to assess whether biomarkers of breast cancer risk are stable across the menstrual cycle, since MCP and MPS variation is likely an important source of biological noise in studies of archived breast biopsy material.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-04-08.

Abstract P6-18-29: Real-world treatment patterns and clinical outcomes with palbociclib combination therapy received in US community oncology practices

Background:

The treatment landscape for women with HR+/HER2- advanced and metastatic breast cancer (A/MBC) is changing as new agents are being combined with more established treatments to achieve greater efficacy in combating resistant and unresponsive disease. The present study is designed to describe patient characteristics, treatment patterns, and clinical outcomes in a cohort of women with HR+/HER2- A/MBC treated with palbociclib plus aromatase inhibitor (P+AI) or palbociclib plus fulvestrant (P+FV) in the US community oncology setting.

Methods:

Retrospective medical record data from adult women diagnosed with HR+/HER2- A/MBC who initiated P+AI or P+FV for treatment of A/MBC on or after February 3, 2015 were collected from the Vector Oncology Data Warehouse, a network comprised of 10 community oncology practices across the US. Descriptive analyses were performed on patient characteristics, treatment patterns, and clinical outcomes. Time to event outcomes (progression-free rate (PFR) and survival rate (SR)) at 12 (PFR-12, SR-12) and 24 (PFR-24, SR-24) months for the P+AI combination as first line endocrine therapy and 12 and 18 months for the P+FV combination as treatment following prior endocrine based therapy in either the adjuvant or metastatic setting.

Results:

Among 304 patients who received palbociclib combination therapy, 281 (92.4%) received it per labeled indication. Of the 281 on-label users, the focus of reporting here, 233 (82.9%) received P+AI as their initial endocrine therapy after A/MBC diagnosis; 48 (17.1%) received P+FV after prior endocrine therapy for breast cancer. Patient mean age (SD) was 63.1 (11.4) and 68.2 (10.2) years for patients receiving P+AI and P+FV, respectively. Patients were predominantly white (74.2% for P+AI and 77.1% for P+FV patients).The initial dosing for palbociclib was 125mg/day in 85.4% (n=199) of P+AI and 79.2% (n=38) of P+FV patients. Among patients who received P+AI, PFR-12 was 69.8% and PFR-24 was 46.8% with median follow up time of 10.8 months and 36.8% of progression events. The SR-12 was 89.8% and SR-24 was 71.4%. For patients who received P+FV, PFR-12 was 43.5% and PFR-18 was 39.9% with a median follow up time of 7.6 months and 50.0% of progression events. The SR-12 was 76.3% and SR-18 was 65.0%.

Conclusions:

This study provides real-world assessment of treatment patterns and clinical outcomes of patients with HR+/ HER2- A/MBC who received palbociclib in combination with an AI or a FV in US community oncology settings. These findings demonstrate the benefit of palbociclib combination therapy in a diverse real world population.

Sponsor: Pfizer, Inc.

Citation Format: Trocio J, Lin J, Fisher MD, Hu N, Davis C, McRoy L, Walker MS, Iyer S. Real-world treatment patterns and clinical outcomes with palbociclib combination therapy received in US community oncology practices [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-29.

Prognostic factors of concurrent chemo-radiotherapy in head and neck cancers

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Background: Concurrent chemo-radiotherapy either as primary or adjuvant treatment is now the standard of care in high- risk head and neck squamous cell carcinomas. This has improved survival rates and chances of organ preservation. Advanced stage, extra- capsular extension, perineural and lympho-vascular invasion and positive surgical margins were considered as poor prognostic factors with radiotherapy alone. Herein we report the significance of these clinical and pathological factors, with concurrent chemo-radiotherapy regimens. Methods:A retrospective analysis of 54 patients with squamous cell carcinoma of head and neck who underwent either primary (21,39 %) or adjuvant (33,61%) concurrent chemoradiation at Amrita Institute of Medical Sciences, Kochi, India, during January 2004 to May 2005 and followed up to Dec 2006. 6 (11%) patients had stage III and 48 (89 %) had stage IV disease. Prognostic significance of clinical and pathological factors was evaluated. Kaplan-Meir curves for survival analysis, log rank test for univariate and Cox proportional method for multivariate analysis were employed. Results: The median follow up was 22 months. Two-year overall (OS) and disease free survival (DFS) rates were 66 % and 52 % respectively. Univariate and multivariate analysis of T stage, nodal stage, radiotherapy interruptions, completion of chemotherapy, schedule of chemotherapy (week 1,4,7 vs weekly), perineural invasion, extra-capsular extension and positive margins showed no significant difference in OS and DFS. However both univariate (p = 0.019 for OS and p = 0.012 for DFS) and multivariate analysis (p = 0.029, HR 0.16,95 %CI - 0.03 to 0.8 for OS and p = 0.017,HR 0.188,95% CI - 0.04 to 0.74 for DFS) revealed lympho-vascular invasion as a significant prognostic factor. Conclusions: Advanced stage, extra capsular invasion and positive margins were conventionally thought to be poor prognostic markers in head and neck cancer. However in our series of patients treated with concurrent chemo radiation lymphovascular invasion was the only significant poor prognostic factor. Other factors were found to be not significant.

No significant financial relationships to disclose.

Pre-onset subthreshold psychotic symptoms are associated with differential treatment delays before a first episode of psychosis: Initial evidence and implications

BACKGROUND

Help-seeking and treatment delays are increasingly critical areas of study in mental health services. The duration of untreated psychosis (DUP), or the time between illness onset and initiation of treatment, is a predictor of symptom remission and functioning for a first episode of psychosis (FEP). The World Health Organization recommends that specialized treatment for psychosis be initiated within the first three months of FEP onset. As a result, research has focused on factors that are associated with threshold-level DUP, while the experience of subthreshold psychotic symptoms (STPS) prior to a FEP may also complicate and present barriers to accessing care for young people. We therefore examine the possibility that STPS can impact DUP and its components.

METHOD

Using a follow-back cross-sectional design, we sought to describe duration of untreated illness, length of prodrome, DUP, help-seeking delay, referral delay, and number of help-seeking contacts among FEP patients who did and did not have STPS prior to psychosis onset.

RESULTS

We found that patients who experienced STPS had a longer median duration of untreated illness, prodrome length, DUP, and help-seeking delay compared to patients who did not have such symptoms. Referral delay did not differ substantially between the two groups. Importantly, treatment delays were extremely lengthy for many participants.

CONCLUSIONS

Pre-onset STPS are associated with help-seeking delays along the pathway to care even during a FEP. Examining early signs and symptoms may help to improve and tailor interventions aimed at reducing treatment delays and ultimately providing timely care when the need arises.

Differences in mannose receptor-mediated uptake of lipoarabinomannan from virulent and attenuated strains of Mycobacterium tuberculosis by human macrophages

Phagocytosis of the virulent Erdman and H37Rv strains of Mycobacterium tuberculosis, but not that of the attenuated H37Ra strain, by human macrophages is mediated by the mannose receptor (MR) in addition to complement receptors. We have recently determined that a major capsular lipoglycan, lipoarabinomannan (LAM), from the Erdman strain serves as a ligand for the MR during phagocytosis of bacteria. In this study we directly compare uptake of Erdman, H37Rv, and H37Ra LAM by human macrophages and assess the relative contribution of the MR in this process. Microspheres coated with LAM served as model phagocytic particles for studies of LAM as a capsular ligand. Uptake (37 degrees C) of LAM microspheres by monocyte-derived macrophages was greatest for Erdman LAM and intermediate for H37Rv and H37Ra LAM compared with that of buffer microspheres or microspheres coated with LAM from a nontuberculosis strain of mycobacterium (AraLAM). Inhibition of microsphere uptake in the presence of mannan or mannose-BSA was highest for Erdman LAM (75 +/- 8 and 50 +/- 7%, respectively) and H37Rv LAM (57 +/- 13 and 21 +/- 5%, respectively) relative to H37Ra LAM (36 +/- 16 and 22 +/- 11 %, respectively). Inhibition of microsphere uptake in the presence of anti-MR Ab followed a similar pattern: Erdman LAM (80 +/- 9%) > H37Rv LAM (53 +/- 1%) > H37Ra LAM (26 +/- 12%). Attachment (4 degrees C) of microspheres coated with Erdman LAM, H37Rv LAM, and H37Ra LAM was enhanced 12-, 5-, and 4-fold, respectively, compared with that of microspheres coated with AraLAM, and mannose-BSA inhibited attachment of these microspheres by 82 +/- 7, 69 +/- 8, and 12 +/- 17%. Galactose-BSA did not inhibit attachment of any LAM microsphere groups. Chromatographic analyses of mild acid hydrolysates of LAM from Erdman, H37Rv, and H37Ra all revealed the major terminal dimannosyl units. These studies demonstrate differences in the ability of LAM from different M. tuberculosis strains to mediate adherence to macrophages and to serve as ligands for the macrophage MR despite the presence of terminal dimannosyl units. Thus, these studies point toward other subtle structural alterations in LAM among strains that influence initial interactions with human phagocytes.

Association of gastroesophageal reflux (GER) with bronchial asthma

Eighty children with bronchial asthma and ten control cases underwent radionuclide gastroesophagography for the detection of gastroesophageal reflux. Thirty nine per cent asthmatic children demonstrated esophageal reflux on scintiscanning. The ten control subjects had no reflux. The presence of reflux correlated strongly with the presence of nocturnal exacerbation of symptoms. Bronchodilator therapy did not affect the prevalence of GER in asthmatic children.

Are we overtreating patients with malignant colorectal polyps? A 5-year review of the ACPGBI position statement

INTRODUCTION

In 2013, The Association of Coloproctology of Great Britain and Ireland (ACPGBI) issued a position statement regarding management of malignant polyps. We reviewed the management of endoscopically resected malignant colorectal polyps in a district general hospital to evaluate whether patients were being overtreated as per these guidelines.

METHODS

All patients who underwent a complete, non-piecemeal endoscopic removal of a malignant polyp between October 2013 and September 2018 were studied. Polyps were risk stratified for residual disease and followed up as per the ACPGBI. Patients were divided into two groups based on management after polypectomy. Primary outcome measured was the presence of residual tumour or involved lymph nodes in the resection specimen. Secondary outcomes included complications and recurrence.

RESULTS

Thirty-three patients were included: 21 in the non-operative group (NOG) and 12 in the operative group (OG). The ACPGBI risk score in the NOG varied between 1 and over 4 compared with the OG who all scored over 4. Two patients in the OG (16%) demonstrated residual disease. Five patients suffered a postoperative complication. No recurrences were noted in the OG and one in the NOG.

CONCLUSION

Our findings against a backdrop of the available literature suggest that the risk of residual disease after malignant polypectomy may not be as high as stated by the ACPGBI. As a result, there is a risk of overtreating patients and exposing them to the significant complications of surgery if careful consideration is not exercised.

Involvement of PARP and poly(ADP-ribosyl)ation in the early stages of apoptosis and DNA replication

We have focused on the roles of PARP and poly(ADP-ribosyl)ation early in apoptosis, as well as during the early stages of differentiation-linked DNA replication. In both nuclear processes, a transient burst of PAR synthesis and PARP expression occurs early, prior to internucleosomal DNA cleavage before commitment to apoptosis as well as at the round of DNA replication prior to the onset of terminal differentiation. In intact human osteosarcoma cells undergoing spontaneous apoptosis, both PARP and PAR decreased after this early peak, concomitant with the inactivation and cleavage of PARP by caspase-3 and the onset of substantial DNA and nuclear fragmentation. Whereas 3T3-L1, osteosarcoma cells, and immortalized PARP +/+ fibroblasts exhibited this early burst of PAR synthesis during Fas-mediated apoptosis, neither PARP-depleted 3T3-L1 PARP-antisense cells nor PARP -/- fibroblasts showed this response. Consequently, whereas control cells progressed into apoptosis, as indicated by induction of caspase-3-like PARP-cleavage activity, PARP-antisense cells and PARP -/- fibroblasts did not, indicating a requirement for PARP and poly(ADP-ribosyl)ation of nuclear proteins at an early reversible stage of apoptosis. In parallel experiments, a transient increase in PARP expression and activity were also noted in 3T3-L1 preadipocytes 24 h after induction of differentiation, a stage at which approximately 95% of the cells were in S-phase, but not in PARP-depleted antisense cells, which were consequently unable to complete the round of DNA replication required for differentiation. PARP, a component of the multiprotein DNA replication complex (MRC) that catalyzes viral DNA replication in vitro, poly(ADP-ribosyl)ates 15 of approximately 40 MRC proteins, including DNA pol alpha, DNA topo I, and PCNA. Depletion of endogenous PARP by antisense RNA expression in 3T3-L1 cells results in MRCs devoid of any DNA pol alpha and DNA pol delta activities. Surprisingly, there was no new expression of PCNA and DNA pol alpha, as well as the transcription factor E2F-1 in PARP-antisense cells during entry into S-phase, suggesting that PARP may play a role in the expression of these proteins, perhaps by interacting with a site in the promoters for these genes.

Abstract P6-18-33: GI toxicities in metastatic breast cancer: A comprehensive literature review

Background

Treatments for advanced or metastatic breast cancer (aBC/mBC) are associated with gastrointestinal (GI) toxicities. The objective of this study was to assess the association between GI toxicities in mBC/aBC and health-related quality of life (HRQoL) and economic burden.

Methods

We conducted a comprehensive literature search of the Cochrane Central Register of Controlled Trials (2017), NHS Economic Evaluation Database (2016), Embase (1988 – 2017 week 34), and Ovid MEDLINE (1946 to August 2017). Eligible studies evaluated an intervention/comparator treatment in adult patients (age ≥18 years) with aBC/mBC and reported a direct connection between GI toxicities (ie, diarrhea, constipation, nausea, vomiting) and HRQoL and economic evidence. All studies published from January 2000 to August 2017 were assessed for eligibility. Editorials, case reports, conference abstracts, and studies of early, locally advanced, or inflammatory BC were excluded. Abstract and title screening, and full-text screening were conducted by single reviewers. Data were extracted by a single reviewer and verified by a second. Results were synthesized narratively.

Results

Database searches identified 3,428 articles; an additional 16 articles were identified through other sources. Ninety-four studies underwent full-text review, of which 27 reported a direct connection between GI toxicities and HRQoL (n = 11) and economic burden (n = 19). Some studies reported both HRQoL and economic data.

Patients identified treatment-related adverse events (AEs), such as GI events, as an important aspect of treatment that can affect therapy choice, discontinuation, and switching. Generally, patients with mBC had lower HRQoL than other BC groups, and increasing toxicity was associated with a greater degree of HRQoL impairment. When patients were asked to rank which AEs they most wanted to avoid, only pain ranked higher than nausea and vomiting. In a willingness to pay study, women with mBC were willing to pay $3,894 (2014 USD) per year to avoid severe diarrhea and $3,211 to avoid severe nausea.

Gastrointestinal events were among the costliest class of AEs, with mean costs as high as $4,809 (2016 USD) per episode; costs increased by 24% if events were persistent or recurrent.

Conclusions

Gastrointestinal toxicities are common in patients with aBC/mBC and have significant consequences for HRQoL and system-level economic outcomes. Frequency and implications of GI effects of treatment regimens should be considered carefully during patient counseling,, prescribing and coverage decisions in metastatic breast cancer.

Citation Format: Disher T, Siddiqui M, Mitra D, Cameron C, Zhan L, Iyer S. GI toxicities in metastatic breast cancer: A comprehensive literature review [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-33.