Neuropathic pain associated with non-surgical treatment of breast cancer

Prescription of pregabalin for prevention of acute post-mastectomy pain syndrome (APMPS): a systematic review and meta-analysis of randomized controlled trials

Background

Mastectomy is generally considered the most effective treatment option for breast cancer. However, it is linked to a variety of complications that contribute to an elevated morbidity. Acute Post Mastectomy Pain Syndrome (APMPS) is 2 months or more of neuropathic pain after mastectomy. Pregabalin, a powerful central nervous system inhibitor is commonly prescribed for the relief of neuropathic pain. This study evaluates its efficacy in curing neuropathic pain and enhancing mastectomy pain management.

Methods

We conducted a comprehensive literature search comparing pregabalin with placebo using relevant syntaxes. Postoperative acute pain scores, 24-hour morphine use, dizziness, and sedation were evaluated. A P-value of less than 0.05 was considered statistically significant.

Results

Ten studies with a total of 719 patients were included. The pregabalin group exhibited significantly lower acute pain scores compared to the placebo group (standard mean difference: -0.61; 95% confidence interval: -1.02 to -0.20; P < 0.01). No statistically significant differences were observed in 24-hour morphine consumption (standardized mean difference, -2.74; 95% CI, -6.27; -0.79, P > 0.05, I 2 = 97.6%), dizziness (RR, 1.49; 95% CI, 0.82; 2.71, P > 0.05, I 2 = 1.0%) or sedation (RR, 1.38; 95% CI, 0.11; 17.84, P > 0.05, I 2 = 0.0%) between the groups. The acute pain scores showed significant heterogeneity, with an I 2 value of 78.6%.

Discussion

This meta-analysis indicates that pregabalin may be effective for managing APMPS. However, due to the heterogeneity and limitations of the included studies, the findings should be interpreted with caution. Future research should focus on larger sample sizes, incorporating potential moderating factors to more precisely determine pregabalin's role in APMPS.

Pain catastrophizing levels differentiate between common diseases with pain: HIV, fibromyalgia, complex regional pain syndrome, and breast cancer survivors

OBJECTIVES

Pain catastrophizing is a core psychological factor determining pain experience. We addressed the question of whether patients with different pain syndromes group into different pain catastrophizing phenotypes.

METHODS

A total of 727 patients with chronic pain associated with four primary syndromes: Breast cancer (BC) survivors (n = 400), fibromyalgia (FM, n = 52), complex regional pain syndrome (CRPS, n = 155), and HIV (n = 120) were first studied for differences in levels of pain catastrophizing (Pain Catastrophizing Scale, PCS) and pain intensity by analysis of variance. Subsequently, individual scores of the PCS subscales "rumination", "magnification," and "helplessness" from the pooled cohorts were submitted to multivariate k-means clustering to explore subgroups.

RESULTS

Three clusters defined by the level of catastrophizing were identified. The "low catastrophizing" cluster (n = 377) included most of the BC patients (71.0%) and the "moderate catastrophizing" cluster (n = 256) most of the FM patients (61.5%). HIV (31.9%) and CRPS (44.7%) patients were over-represented in the "high catastrophizing" cluster (n = 94) with the highest catastrophizing tendencies in all dimensions. These patients reported more helplessness than the patients in the two other clusters.

CONCLUSIONS

The primary syndrome causing the pain has an impact on self-reported pain-related catastrophizing. Helplessness is a predominant feature in HIV and CRPS patients and therefore an important target in pain rehabilitation.

Pain associated with breast cancer: etiologies and therapies

Pain associated with breast cancer is a prevalent problem that negatively affects quality of life. Breast cancer pain is not limited to the disease course itself but is also induced by current therapeutic strategies. This, combined with the increasing number of patients living with breast cancer, make pain management for breast cancer patients an increasingly important area of research. This narrative review presents a summary of pain associated with breast cancer, including pain related to the cancer disease process itself and pain associated with current therapeutic modalities including radiation, chemotherapy, immunotherapy, and surgery. Current pain management techniques, their limitations, and novel analgesic strategies are also discussed.

Postmastectomy Pain Syndrome: A Narrative Review

Postmastectomy pain syndrome is a very common disorder in breast cancer survivors. The impact on the quality of patients' lives is significantly adverse. The precise pathophysiology has not been determined as yet though various risk factors have been identified that make the patient vulnerable. Required preoperative work includes the identification and possible elimination of risk factors. Treatment is multidisciplinary involving surgical and non-surgical modalities. There is a great scope of research in this field.

Association between chronic pain and quality of life in long-term breast cancer survivors: a prospective analysis

PURPOSE

Pain is a leading cause of disability worldwide and is highly prevalent among breast cancer survivors. Pain and quality of life (QOL) are associated in breast cancer patients undergoing active treatment, but little is known about the relationship between the two in long-term survivors.

METHODS

We evaluated associations between pain information collected during a 5-year post-diagnosis follow-up survey and QOL assessed by the SF-36 during a 10-year post-diagnosis survey for 2828 participants in the Shanghai Breast Cancer Survival Study.

RESULTS

The mean overall QOL score was 78.7 for the entire study population and decreased as pain severity and frequency measured at the 5-year timepoint increased (none: 81.9, mild: 75.9, moderate/severe: 70.4, infrequent: 76.7, frequent: 72.3; P < 0.001). Significant inverse associations were found between pain and all QOL domains, including pain at 10-years post-diagnosis after multivariate adjustments. Concurrent pain was significantly and strongly associated with QOL. Most of the associations between 5-years post-diagnosis pain and QOL at 10-years post-diagnosis persisted after further adjustment for concurrent pain.

CONCLUSIONS

Pain is associated prospectively and concurrently with poor QOL among long-term breast cancer survivors. Programs to manage pain are needed to improve QOL among breast cancer survivors.

Treating Pain and Fat Necrosis after Breast Cancer Surgery with Fat Grafting: Is one Session Enough?

BACKGROUND

Chronic pain after breast cancer surgery is affecting up to 60% of patients, causing significant morbidity to patients. Lately, fat grafting has been applied as a therapy for chronic neuropathic pain.

METHODS

We report a series of eighteen patients, who were treated for pain after breast cancer surgery. Twelve patients had a breast conserving therapy, two a mastectomy and four an autologous flap-based reconstruction. While most presented with neuropathic pain, six patients had fat necrosis in their history. Most patients presented with severe pain (77%) and were treated with fat grafting sessions, performed by water-assisted liposuction.

RESULTS

All patients responded to the interventions; the median number of fat grafting sessions was 2, the median duration of the interventions was 4 months, and the median follow-up period was 56.5 months. The median pain prior to the fat grafting procedure had an intensity of 8 (range 7-9) numeric rating scale points; after the first intervention, this was reduced to 4 (range 2.3-5.8); and after the second intervention, it was down to 2 (range 0.8-3.3). Patients with pain intensities of 4-5 had a good chance of achieving analgesia after one session.

CONCLUSIONS

Fat grafting could be a new treatment modality for symptomatic fat necrosis: complete or partial suction of the necrosis and/or fat grafting around the necrosis to reduce inflammation and pain. Fat grafting proved a valuable tool, reducing pain or even achieving analgesia after breast cancer surgery presenting with a highly favorable risk-benefit ratio.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Breast reconstruction after breast cancer surgery - persistent pain and quality of life 1-8 years after breast reconstruction

OBJECTIVES

To assess the long-term outcome of breast reconstructions with special focus on chronic postsurgical pain (CPSP) in a larger cohort of breast cancer survivors.

METHODS

A cross-sectional study on 121 women with mastectomy and breast reconstruction after mean 2 years 4 months follow up. The mean time from breast reconstruction to the follow-up visit was 4 years 2 months. We studied surveys on pain (Brief Pain Inventory, BPI and Douleur Neuropathique 4, DN4), quality of life (RAND-36 health survey), sleep (insomnia severity questionnaire, ISI), mood (Beck's Depression Index, BDI; Hospital Anxiety and Depression Scale, HADS), and a detailed clinical sensory status. Patients were divided into three groups: abdominal flap (Deep inferior epigastric perforator flap, DIEP; Free transverse rectus abdominis flap, fTRAM, and Pedicled transverse rectus abdominis flap, pTRAM), dorsal flap (Latissimus dorsi flap, LD and Thoracodorsal artery perforator flap, TDAP), and other (Transverse myocutaneous gracilis flap, TMG; implant). Clinically meaningful pain was defined ≥ 4/10 on a numeric rating scale (NRS). We used patients' pain drawings to localize the pain. We assessed preoperative pain NRS from previous data.

RESULTS

106 (87.6%) of the patients did not have clinically meaningful persistent pain. We found no statistically significant difference between different reconstruction types with regards to persistent pain (p=0.40), mood (BDI-II, p=0.41 and HADS A, p=0.54) or sleep (p=0.14), respectively. Preoperative pain prior to breast reconstruction surgery correlated strongly with moderate or severe CPSP.

CONCLUSIONS

Moderate to severe CPSP intensity was present in 14% of patients. We found no significant difference in the prevalence of pain across different reconstruction types. Preoperative pain associated significantly with postoperative persistent pain.

Epidemiology and Predictive Factors for Persistent Breast Pain Following Breast-Conserving Surgery

Background

In general, breast pain is one of the most common causes for referral to breast units; treatment-related breast pain is frequently seen in clinical practice but not well addressed in the literature. While our primary objective was to identify the incidence of persistent breast pain following breast-conserving surgery and possible risk factors, our secondary aim was to assess the possibility of using a breast ultrasound scan to detect parenchymal changes that can contribute to breast pain.

Methods

We have conducted a prospective study including patients who had wide local excision for primary breast cancer treatment between January 2017 and January 2019. Patients’ demographics, including age, BMI, breast volume, and tumour characteristics, were noted. All patients had a clinical assessment and were asked standard questions about their breast pain each visit; they also had an ultrasound scan of the breast and axilla 6 and 12 months after surgery to look for parenchymal changes.

Results

A total of 239 female breast cancer patients were included in our analysis. The mean age was 43.9 years, mean weight was 72.8 kg, mean BMI was 27.4 and mean breast volume was 1173 ml. In total, 38.5% had standard wide local excision, and 61.5% had oncoplastic resection; the mean specimen weight was 74.6 grams. All patients had adjuvant whole breast radiotherapy. We found that patients with younger age, larger breast size, high BMI, oncoplastic resections, and persistent parenchymal changes are associated with an increased incidence of postoperative breast pain while the type of axillary procedure and adjuvant chemotherapy had no significant effect.

Conclusion

Persistent postoperative breast pain was noted in 33% of our patients. We have also indicated that younger patients, patients with larger breast, those with high BMI, with preoperative breast pain, who had oncoplastic resections, and patients with persistent parenchymal changes, as fat necrosis and scarring, are associated more with persistent breast pain.

Inhibition of autotaxin activity ameliorates neuropathic pain derived from lumbar spinal canal stenosis

Lumbar spinal canal stenosis (LSS) or mechanical compression of dorsal root ganglion (DRG) is one of the causes of low back pain and neuropathic pain (NP). Lysophosphatidic acid (LPA) is a potent bioactive lipid mediator that is produced mainly from lysophosphatidylcholine (LPC) via autotaxin (ATX) and is known to induce NP via LPA1 receptor signaling in mice. Recently, we demonstrated that LPC and LPA were higher in cerebrospinal fluid (CSF) of patients with LSS. Based on the possible potential efficacy of the ATX inhibitor for NP treatment, we used an NP model with compression of DRG (CD model) and investigated LPA dynamics and whether ATX inhibition could ameliorate NP symptoms, using an orally available ATX inhibitor (ONO-8430506) at a dose of 30 mg/kg. In CD model, we observed increased LPC and LPA levels in CSF, and decreased threshold of the pain which were ameliorated by oral administration of the ATX inhibitor with decreased microglia and astrocyte populations at the site of the spinal dorsal horn projecting from injured DRG. These results suggested possible efficacy of ATX inhibitor for the treatment of NP caused by spinal nerve root compression and involvement of the ATX-LPA axis in the mechanism of NP induction.

A Comprehensive Review of the Diagnosis, Treatment, and Management of Postmastectomy Pain Syndrome

PURPOSE OF REVIEW

Postmastectomy pain syndrome (PMPS) remains poorly defined, although it is applied to chronic neuropathic pain following surgical procedures of the breast, including mastectomy and lumpectomy in breast-conserving surgery. It is characterized by persistent pain affecting the anterior thorax, axilla, and/or medial upper arm following mastectomy or lumpectomy. Though the onset of pain is most likely to occur after surgery, there may also be a new onset of symptoms following adjuvant therapy, including chemotherapy or radiation therapy.

RECENT FINDINGS

The underlying pathophysiology is likely multifactorial, although exact mechanisms have yet to be elucidated. In this regard, neuralgia of the intercostobrachial nerve is currently implicated as the most common cause of PMPS. Numerous pharmacological options are available in the treatment of PMPS, including gabapentinoids, tricyclic antidepressants, selective serotonin reuptake inhibitors, NMDA receptor antagonists, and nefopam (a non-opioid, non-steroidal benzoxazocine analgesic). Minimally invasive interventional treatment including injection therapy, regional anesthesia, botulinum toxin, and neuromodulation has been demonstrated to have some beneficial effect. A comprehensive update highlighting current perspectives on the treatment of postmastectomy pain syndrome is presented with emphasis on treatments currently available and newer therapeutics currently being evaluated to alleviate this complex and multifactorial condition.

Association between cancer stigma, pain and quality of life in breast cancer

Aim

We examined the association between cancer stigma and quality of life. We further explored the role of pain intensity in this association among women with breast cancer in the first months following diagnosis.

Methods

105 women with breast cancer within 8 months of diagnosis completed self-report measures assessing cancer stigma, pain intensity and quality of life.

Results

Our findings show that stigma among breast cancer patients is associated with worse quality of life. Pain intensity partially mediated the relationship between cancer stigma and quality of life. We recruited a convenience sample of women with breast cancer, which may be subject to selection bias. The cross sectional design of the study precludes inferences regarding causality.

Conclusions

Health professionals should recognize and mitigate the impact of stigma as an important factor that is associated with impaired quality of life among patients with breast cancer. Continued attention should be paid to pain intensity and the complex relationship between stigma and pain in predicting quality of life.

Self-reported pain in breast cancer patients receiving adjuvant radiotherapy

PURPOSE

Breast cancer patients receiving radiotherapy (RT) commonly report pain, contributing to physical and emotional distress, and potentially resulting in poor quality of life. This study prospectively identified trends and risk factors in patient-reported pain associated with breast irradiation using the Edmonton Symptom Assessment Scale (ESAS) and a study-specific Skin Symptom Assessment (SSA).

METHODS

Before RT and once per week during RT, patients completed the ESAS and SSA. Upon RT completion, patients were contacted via telephone to complete both assessments weekly for 6 weeks, and a final assessment was conducted 1-3 months post-RT. Only data from patients who had completed both assessments before, at least once during, and at least once after RT were included in our analysis.

RESULTS

A total of 426 patients provided data for the analysis. Overall acute pain increased significantly at week 1-2 (p < 0.0001), week 5 (p = 0.0011), and at 1-3 months (p < 0.0001) post-RT compared with baseline, and acute breast pain increased significantly at week 1 (p < 0.001) and week 2 (p = 0.0002) post-RT compared with baseline. Previous chemotherapy (adjuvant or neoadjuvant) in mastectomy patients was associated with increased overall pain compared with mastectomy patients without previous chemotherapy (p = 0.017). Younger patients (40-49 or 50-59 years of age) reported more overall pain (p = 0.0001, p = 0.038) and breast pain (p = 0.0003, p = 0.0038) compared with patients ≥ 60 years of age.

CONCLUSIONS

Patient-reported pain associated with breast irradiation peaked 1 week after RT completion. Our findings provide support for closer monitoring of acute pain associated with breast RT in younger patients.

Association between long-term NSAID use and opioid abuse among patients with breast cancer

BACKGROUND

Improving survival rates among patients with breast cancer has been associated with an increase in the prevalence of co-morbidities like cancer-related pain. Opioids are an important component in the management of pain among these patients. However, the progression from judicious use to abuse defeats the aim of pain control. Non-steroidal anti-inflammatory drugs (NSAIDs) are recommended as the first step in cancer-related pain management. Due to their anti-inflammatory, anti-neoplastic and neuroprotective properties, NSAIDs have been shown to reduce the risk of progression of certain cancers including breast cancers. In this study, we assessed whether an association exists between long-term NSAID use and opioid abuse among breast cancer survivors. We also explored the relationship between long-term NSAID use and inpatient mortality and length of stay (LOS).

METHODS

Using ICD-9-CM codes, we identified and selected women aged 18 years and older with breast cancer from the National Inpatient Sample. Our primary predictor was a history of long-term NSAID use. Multivariable regression models were employed in assessing the association between long-term NSAID use and opioid abuse, inpatient mortality and LOS.

RESULTS

Among 170,644 women with breast cancer, 7,838 (4.6%) reported a history of long-term NSAID use. Patients with a history of long-term NSAID use had lower odds of opioid abuse (adjusted odds ratio (aOR) 0.53; 95% CI [0.32-0.88]), lower in-hospital mortality (aOR 0.52; 95% CI [0.45-0.60]) and shorter LOS (7.12 vs. 8.11 days).

DISCUSSION

Further studies are needed to understand the underlying mechanism of the association between long-term NSAID use and opioid abuse.

Factors Associated With New Persistent Opioid Usage After Lung Resection

BACKGROUND

Opioid dependence, misuse, and abuse in the United States continue to rise. Prior studies indicate an important risk factor for persistent opioid use includes elective surgical procedures, though the probability following thoracic procedures remains unknown. We analyzed the incidence and factors associated with new persistent opioid use after lung resection.

METHODS

We evaluated data from opioid-naïve cancer patients undergoing lung resection between 2010 and 2014 using insurance claims from the Truven Health MarketScan Databases. New persistent opioid usage was defined as continued opioid prescription fills between 90 and 180 days following surgery. Variables with a p value less than 0.10 by univariate analysis were included in a multivariable logistic regression performed for risk adjustment. Multivariable results were each reported with odds ratio (OR) and confidence interval (CI).

RESULTS

A total of 3,026 patients (44.8% men, 55.2% women) were identified as opioid-naïve undergoing lung resection. Mean age was 64 ± 11 years and mean postoperative length of stay was 5.2 ± 3.3 days. A total of 6.5% underwent neoadjuvant therapy, while 21.7% underwent adjuvant therapy. Among opioid-naïve patients, 14% continued to fill opioid prescriptions following lung resection. Multivariable analysis showed that age less than or equal to 64 years (OR, 1.28; 95% CI, 1.03 to 1.59; p = 0.028), male sex (OR, 1.40; 95% CI, 1.13 to 1.73; p = 0.002), postoperative length of stay (OR, 1.32; 95% CI, 1.05 to 1.65; p = 0.016), thoracotomy (OR, 1.58; 95% CI, 1.24 to 2.02; p < 0.001), and adjuvant therapy (OR, 2.19; 95% CI, 1.75 to 2.75; p < 0.001) were independent risk factors for persistent opioid usage.

CONCLUSIONS

The greatest risk factors for persistent opioid use (14%) following lung resection were adjuvant therapy and thoracotomy. Future studies should focus on reducing excess prescribing, perioperative patient education, and safe opioid disposal.

Colored body images reveal the perceived intensity and distribution of pain in women with breast cancer treated with adjuvant taxanes: a prospective multi-method study of pain experiences

Background and aims Breast cancer is the most prevalent adult cancer worldwide. A broader use of screening for early detection and adjuvant systemic therapy with chemotherapy has resulted in improved survival rates. Taxane-containing chemotherapy is one of the cornerstones of the treatment. However, taxane-containing chemotherapy may result in acute chemotherapy-induced nociceptive and neuropathic pain. Since this pain may be an additional burden for the patient both during and after taxane chemotherapy, it is important to rapidly discover and treat it. There is yet no gold standard for assessing taxane-induced pain. In the clinic, applying multiple methods for collecting information on pain may better describe the patients' pain experiences. The aim was to document the pain during and after taxane through the contribution of different methods for collecting information on taxane-induced pain. Fifty-three women scheduled for adjuvant sequential chemotherapy at doses of ≥75 mg/m2 of docetaxel and epirubicin were enrolled in the study. Methods Prospective pain assessments were done on a visual analog scale (VAS) before and during each cycle of treatment for about 5 months, and using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire's (EORTC-QLQ-C30) two pain questions at baseline, 3 months, and 12 months. Participants scoring pain on the VAS >30 and undergoing an interview also colored their pain on a body image during treatment and at 12 months. Results Surprisingly widespread, intense pain was detected using a multi-method approach. The colored body image showed pain being perceived on 51% of the body surface area during treatment, and on 18% 12 months after inclusion. In general, the pain started and peaked in intensity after the first cycle of taxane. After Cycle 3, most women reported an increase in pain on the VAS. Some women continued to report some pain even during the epirubicin cycles. The VAS scores dropped after the last chemotherapy cycle, but not to the baseline level. At baseline, 3 months and 12 months after inclusion, the women who estimated VAS >30 reported higher levels of pain on the pain questions of the EORTC-QLQ-C30. Conclusions This study contributes information on how different pain assessment tools offer different information in the assessment of pain. The colored body image brings another dimension to pain diagnostics, providing additional information on the involved body areas and the pain intensities as experienced by the women. A multi-method approach to assessing pain offers many advantages. The timing of the assessment is important to properly assess pain. Implications Pain relief needs to be included in the chemotherapy treatment, with individual assessment and treatment of pain, in the same way as is done in chemotherapy-triggered nausea. There is a time window whereby the risk of pain development is at its highest within 24-48 h after receiving taxane chemotherapy. Proper attention to pain evaluation and treatment should be in focus during this time window.

The Impact of Education and Prescribing Guidelines on Opioid Prescribing for Breast and Melanoma Procedures

BACKGROUND

Excessive opioid prescribing is common in surgical oncology, with 72% of prescribed opioids going unused after curative-intent surgery. In this study, we sought to reduce opioid prescribing after breast and melanoma procedures by designing and implementing an intervention focused on education and prescribing guidelines, and then evaluating the impact of this intervention.

METHODS

In this single-institution study, we designed and implemented an intervention targeting key factors identified in qualitative interviews. This included mandatory education for prescribers, evidence-based prescribing guidelines, and standardized patient instructions. After the intervention, interrupted time-series analysis was used to compare the mean quantity of opioid prescribed before and after the intervention (July 2016-September 2017). We also evaluated the frequency of opioid prescription refills.

RESULTS

During the study, 847 patients underwent breast or melanoma procedures and received an opioid prescription. For mastectomy or wide local excision for melanoma, the mean quantity of opioid prescribed immediately decreased by 37% after the intervention (p = 0.03), equivalent to 13 tablets of oxycodone 5 mg. For lumpectomy or breast biopsy, the mean quantity of opioid prescribed decreased by 42%, or 12 tablets of oxycodone 5 mg (p = 0.07). Furthermore, opioid prescription refills did not significantly change for mastectomy/wide local excision (13% vs. 14%, p = 0.8), or lumpectomy/breast biopsy (4% vs. 5%, p = 0.7).

CONCLUSION

Education and prescribing guidelines reduced opioid prescribing for breast and melanoma procedures without increasing the need for refills. This suggests further reductions in opioid prescribing may be possible, and provides rationale for implementing similar interventions for other procedures and practice settings.

Opioid Prescribing After Curative-Intent Surgery: A Qualitative Study Using the Theoretical Domains Framework

BACKGROUND

Excessive opioid prescribing is common after curative-intent surgery, but little is known about what factors influence prescribing behaviors among surgeons. To identify targets for intervention, we performed a qualitative study of opioid prescribing after curative-intent surgery using the Theoretical Domains Framework, a well-established implementation science method for identifying factors influencing healthcare provider behavior.

METHODS

Prior to data collection, we constructed a semi-structured interview guide to explore decision making for opioid prescribing. We then conducted interviews with surgical oncology providers at a single comprehensive cancer center. Interviews were recorded, transcribed verbatim, then independently coded by two investigators using the Theoretical Domains Framework to identify theoretical domains relevant to opioid prescribing. Relevant domains were then linked to behavior models to select targeted interventions likely to improve opioid prescribing.

RESULTS

Twenty-one subjects were interviewed from November 2016 to May 2017, including attending surgeons, resident surgeons, physician assistants, and nurses. Five theoretical domains emerged as relevant to opioid prescribing: environmental context and resources; social influences; beliefs about consequences; social/professional role and identity; and goals. Using these domains, three interventions were identified as likely to change opioid prescribing behavior: (1) enablement (deploy nurses during preoperative visits to counsel patients on opioid use); (2) environmental restructuring (provide on-screen prompts with normative data on the quantity of opioid prescribed); and (3) education (provide prescribing guidelines).

CONCLUSIONS

Key determinants of opioid prescribing behavior after curative-intent surgery include environmental and social factors. Interventions targeting these factors are likely to improve opioid prescribing in surgical oncology.

Is neuropathic pain associated with cardiac sympathovagal activity changes in patients with breast cancer?

Objective Heart rate variability (HRV) is a good indicator of the autonomic nervous system (ANS) activity. A few studies have been conducted recently and have shown a relationship between reduced HRV and conditions that lead to neuropathic pain (NP). In this study, we aimed to investigate whether NP is associated with changes in cardiac sympathovagal activity in patients with breast cancer (BC). Methods We used the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) questionnaire to evaluate NP in 70 patients with BC. The patients were subjected to a 24-h Holter ECG monitorization to determine heart rate variability (HRV). Standard deviation (SD) of the normal-to-normal RR intervals (SDNN), SD of the mean of the RR intervals (SDAAN), mean of the SD of the NN interval (SDNN Index), low-frequency component/high-frequency component ratio (LF/HF), and the mean heart rate of the patients were recorded. Results According to the LANSS questionnaire, 18 (25.7%) of the patients were classified as NP (+). The SDNN (P = 0.001), SDAAN (P = 0.003), and SDDN index (P = 0.007) were significantly lower in patients with NP than in patients without NP, whereas LF/HF ratio (P = 0.000) and mean heart rate were found to be significantly higher in patients with NP (P = 0.006). Conclusion According to our findings, NP (+) patients with BC had increased cardiac sympathetic activity, which was suggested to be associated with increased cardiovascular morbidity and mortality.

Chronic postsurgical pain following breast reconstruction: a commentary and critique

In line with other major surgeries including breast cancer surgery (BCS), recent studies suggest a striking rate of chronic postsurgical pain (CPSP) following breast reconstruction. This commentary will critically examine evidence for the degree to which the prevalence of CPSP following breast reconstruction is directly attributable to reconstructive surgery. The discussion will trace similarities and distinctions between breast reconstruction and BCS in considering the risk for CPSP, and describe recent advances in the definition of CPSP, highlighting methodological limitations in the general investigation of CPSP, which also characterize the study of CPSP more specifically for breast reconstruction outcome. A convenience sample of relevant studies examining CPSP following breast reconstruction reveals inadequate evidence to support a serious concern for reconstruction-induced CPSP and further that these studies fail to adhere to recommended methodological standards to effectively isolate surgery as the etiology of persistent pain reported by women following reconstructive surgery. Suggestions for future exploration of problematic chronic pain after breast reconstruction are considered.

Neuropathic Pain After Breast Cancer Treatment: Characterization and Risk Factors

CONTEXT

Neuropathic pain (NP) may be an important contributor to the morbidity burden of breast cancer.

OBJECTIVES

We aimed to quantify the incidence of NP in the first year after diagnosis of breast cancer and to identify its main determinants.

METHODS

We performed a prospective cohort study including 506 patients with incident breast cancer, recruited at the Portuguese Institute of Oncology of Porto, and followed for one year; patients with incident NP were additionally evaluated when this condition was diagnosed and after six months, to identify chronic NP.

RESULTS

During the first year, 156 patients were diagnosed with NP (30.8%, 95% CI 27.0-35.0). Anxiety (relative risk [RR] 1.50; 95% CI 1.06-2.13), arm symptoms (RR 1.44; 95% CI 1.02-2.05), cancer Stage III/IV (RR 2.47; 95% CI 1.66-3.66), breast-conserving surgery with axillary lymph node dissection (RR 3.13; 95% CI 1.51-6.48), mastectomy with axillary lymph node dissection (RR 2.52; 95% CI 1.25-5.11), and damaging of the intercostobrachial nerve (RR 2.05; 95% CI 1.25-3.37) were predictors of a higher risk of NP. A total of 97 patients (62.2%, 95% CI 54.4-69.4) diagnosed with NP remained symptomatic after six months.

CONCLUSION

NP and chronic NP were frequent in this population, being associated with anxiety and arm symptoms before breast cancer treatments and type of surgical management. These results highlight the need for monitoring the occurrence of this neurologic side effect of treatments and to develop strategies for reducing the morbidity burden of breast cancer.

Is chronic postsurgical pain surgery-induced? A study of persistent postoperative pain following breast reconstruction

BACKGROUND

Chronic postsurgical pain (CPSP) is a reported risk for women undergoing breast reconstruction, but it remains unclear that such persistent pain is induced by reconstructive surgery. To address this concern, this prospective cohort study examined the prevalence of and risk factors associated with CPSP among women undergoing breast reconstruction.

MATERIALS AND METHODS

Women (n = 1996) recruited for the Mastectomy Reconstruction Outcomes Consortium (MROC) Study were assessed preoperatively and at two-years postoperatively for relevant medical/.surgical variables, pain experience, body physical well-being, anxiety, depression, and reconstruction procedure type and characteristics.

RESULTS

Nearly half of the entire sample reported some level of preoperative pain. At two years there were statistically significant but not clinically meaningful increases in both pain intensity and chest/upper body discomfort but a decrease in affective pain rating. Average clinical pain severity was strikingly similar for preoperative and postoperative assessments. Preoperative levels of pain, acute postoperative pain, and (marginally) level of depression held consistent relationship at two-year follow-up with all outcome measures. Autologous flap reconstruction was associated with more severe CPSP compared to TE/I reconstruction. Older age, higher BMI, bilateral reconstruction, and adjuvant radiation and chemotherapy were associated with CPSP and chest/upper body discomfort for at least one outcome measure at two years.

CONCLUSIONS

The substantial rate of preoperative pain and comparable prevalence of preoperative and postoperative pain ratings suggest that persistent pain after breast reconstruction may not necessarily reflect surgery-induced pain. Future research will need to determine those factors that contribute to long-term pain following breast reconstruction.

New Persistent Opioid Use Among Patients With Cancer After Curative-Intent Surgery

Purpose The current epidemic of prescription opioid misuse has increased scrutiny of postoperative opioid prescribing. Some 6% to 8% of opioid-naïve patients undergoing noncancer procedures develop new persistent opioid use; however, it is unknown if a similar risk applies to patients with cancer. We sought to define the risk of new persistent opioid use after curative-intent surgery, identify risk factors, and describe changes in daily opioid dose over time after surgery. Methods Using a national data set of insurance claims, we identified patients with cancer undergoing curative-intent surgery from 2010 to 2014. We included melanoma, breast, colorectal, lung, esophageal, and hepato-pancreato-biliary/gastric cancer. Primary outcomes were new persistent opioid use (opioid-naïve patients who continued filling opioid prescriptions 90 to 180 days after surgery) and daily opioid dose (evaluated monthly during the year after surgery). Logistic regression was used to identify risk factors for new persistent opioid use. Results A total of 68,463 eligible patients underwent curative-intent surgery and filled opioid prescriptions. Among opioid-naïve patients, the risk of new persistent opioid use was 10.4% (95% CI, 10.1% to 10.7%). One year after surgery, these patients continued filling prescriptions with daily doses similar to chronic opioid users ( P = .05), equivalent to six tablets per day of 5-mg hydrocodone. Those receiving adjuvant chemotherapy had modestly higher doses ( P = .002), but patients with no chemotherapy still had doses equivalent to five tablets per day of 5-mg hydrocodone. Across different procedures, the covariate-adjusted risk of new persistent opioid use in patients receiving adjuvant chemotherapy was 15% to 21%, compared with 7% to 11% for those with no chemotherapy. Conclusion New persistent opioid use is a common iatrogenic complication in patients with cancer undergoing curative-intent surgery. This problem requires changes to prescribing guidelines and patient counseling during the surveillance and survivorship phases of care.

Optimizing post-acute care in breast cancer survivors: a rehabilitation perspective

Breast cancer (BC) is the most common malignancy and a leading cause of morbidity and mortality in women worldwide. Therapeutic advances and improved survival rates of women with BC have implications for long-term impact on disability, psychological function and quality of life (QoL), which may be amenable to rehabilitation. The focus of rehabilitation is on managing disability, reducing sequelae and symptoms, and enhancing participation and societal reintegration, to achieve the highest possible independence and the best QoL. Rehabilitation interventions should be considered early for maintaining functional capacity and reducing the risk of losing important abilities or independence and should be individualized depending on disease phase, functional deficits, personal requirements and specific goals. A number of interventions have been trialled to support rehabilitation input for women with BC, which include physical therapy, psychological interventions (psychotherapy, cognitive behavioral training) and others. Multidisciplinary rehabilitation and uni-disciplinary interventions such as physical therapy have been shown to be beneficial in reducing disability, and improving participation and QoL. There is a need for comprehensive assessment of health domains in BC patients using a standardized framework and a common language for describing the impact of disease at different levels, using the International Classification of Functioning, Disability and Health core sets. This will provide more detailed information on the needs of these patients, so more efficient and targeted rehabilitation interventions can be provided.

Neuropathic pain after breast cancer treatment and its impact on sleep quality one year after cancer diagnosis

OBJECTIVES

Data regarding the impact of breast cancer treatment-related neuropathic pain (NP) on sleep quality are scarce. Therefore, we aimed to assess the impact of breast cancer treatment-related NP on patients' sleep quality, during the first year after cancer diagnosis.

MATERIALS AND METHODS

A total of 501 breast cancer patients were followed prospectively. Incident NP was identified through systematic evaluations after treatments and one year after enrolment. NP severity was quantified using the Brief Pain Inventory severity subscale and sleep quality was evaluated through the Pittsburgh Sleep Quality Index (PSQI), at baseline and after one year. Adjusted regression coefficients (β) and 95% confidence intervals (95%CI) were used to quantify the relation between NP and the variation in the PSQI z-scores.

RESULTS

The occurrence of NP was associated with a deterioration in sleep quality during the first year of follow-up, more pronounced among those with good sleep quality (PSQI≤5) than those with poor sleep quality at baseline (PSQI>5) (β = 0.44, 95%CI: 0.11 to 0.77 versus β = 0.33, 95%CI: 0.08 to 0.59). These differences were accentuated when only the cases of NP with greater severity were considered (β = 0.86, 95%CI: 0.37 to 1.35 versus β = 0.31, 95%CI: -0.08 to 0.64). Within the PSQI components, daytime dysfunction and sleep duration were the most impaired by NP.

CONCLUSION

Our findings highlight the importance of the promotion of sleep hygiene among breast cancer patients diagnosed with NP, especially among those with good sleep quality before treatments.

Chronic pain in breast cancer survivors: comparison of psychosocial, surgical, and medical characteristics between survivors with and without pain

CONTEXT

According to the literature, 25%-60% of women treated for breast cancer, regardless of the stage, experience pain. Many risk factors have been suggested, with many possible confounding factors.

OBJECTIVES

The aim was to investigate psychosocial, surgical, and medical factors associated with chronic pain by comparing breast cancer survivors with chronic pain with survivors without chronic pain. In addition, we investigated the prevalence, intensity, and body location of chronic pain after breast cancer treatment nationwide.

METHODS

A nationwide postal survey of 1332 women who received surgery and adjuvant therapy for breast cancer in Norway two to six years before the onset of this study.

RESULTS

A total of 832 women (63%) returned the questionnaires, and 41% reported pain, of which 51% had mild, 41% moderate, and 8% severe pain. Among the women who experienced pain, 33.8% reported symptoms and signs of neuropathic pain. Young age (odds ratio [OR], 0.95; 95% CI, 0.93-0.98; P < 0.0001), axillary lymph node dissection with subsequent chemotherapy and radiotherapy (OR, 1.69; 95% CI, 1.07-2.67; P = 0.02), other illness that caused pain (OR, 2.37; 95% CI, 1.72-3.26; P < 0.0001), depression (OR, 2.07; 95% CI, 1.25-3.40; P = 0.004), and anxiety (OR, 1.83; 95% CI, 1.26-2.66; P = 0.002) were associated with chronic pain.

CONCLUSION

Young age, previous comorbidities (such as back pain, arthritis, arthrosis, and fibromyalgia), and combined treatment with axillary lymph node dissection, chemotherapy, and radiotherapy were risk factors for chronic pain. Whether depression or anxiety is a risk factor for chronic pain remains unclear.

Neurological complications of breast cancer: study protocol of a prospective cohort study

INTRODUCTION

The improvement in breast cancer survival rates, along with the expected overdiagnosis and overtreatment associated with breast cancer screening, requires a comprehensive assessment of its burden. Neurological complications can have a devastating impact on these patients; neuropathic pain and chemotherapy-induced peripheral neuropathy are among the most frequently reported. This project aims to understand the burden of neurological complications of breast cancer treatment in Northern Portugal, and their role as mediator of the impact of the treatment in different dimensions of the patients' quality of life.

METHODS AND ANALYSIS

A prospective cohort study was designed to include 500 patients with breast cancer, to be followed for 3 years. The patients were recruited at the Portuguese Oncology Institute of Porto and evaluations were planned at different stages: pretreatment, after surgery, after chemotherapy (whenever applicable) and at 1 and 3 years after enrolment. Patients diagnosed with neuropathic pain or chemotherapy-induced peripheral neuropathy (subcohorts), were also evaluated at the moment of confirmation of clinical diagnosis of the neurological complication and 6 months later. In each of the follow-up periods, a neurological examination has been performed by a neurologist. Data were collected on sociodemographic and clinical characteristics, quality of life, sleep quality, and anxiety and depression. Between January and December 2012, we recruited and conducted the baseline evaluation of 506 participants. The end of the follow-up period is scheduled for December 2015.

ETHICS AND DISSEMINATION

The study protocol was approved by the Ethics Committee of the Portuguese Oncology Institute of Porto and all patients provided written informed consent. All study procedures were developed in order to assure data protection and confidentiality. Results from this project will be disseminated in international peer-reviewed journals and presented in relevant conferences.

Persistent postsurgical pain

PURPOSE OF REVIEW

Persistent postsurgical pain (PPP) is an important cause of pain morbidity following surgery for almost any cause, but there is a greater evidence base for pain after cancer surgery. Historically, both patients and practitioners have struggled to recognize and accept this growing problem. This review will seek to highlight the awareness of this increasing epidemic and will discuss evidence base for diagnosis, risk factors and current strategies for prevention and treatment, especially after cancer surgery.

RECENT FINDINGS

Given the potential size of the problems of PPP, there is a relative paucity of recent data, especially as regards effective treatments. The review will synthesize current and existing evidence to give a balanced up-to-date view. There is a clear need for more high-quality randomized trials.

SUMMARY

An estimated 40,000 patients in the UK will develop PPP, of whom at least 5-10% will have severe pain. Lack of clear definition and lack of awareness have been barriers to diagnosis and access to treatment. Several risk factors associated with PPP have been identified and reduction of these factors may prevent its development. At present, there are large gaps in the evidence base and more large controlled trials are warranted.

A retrospective study of postmastectomy pain syndrome: incidence, characteristics, risk factors, and influence on quality of life

Objective. The underlying cause for postmastectomy pain syndrome (PMPS) and its impact on quality of life remain unclear. The objective of this study aims to determine retrospectively the prevalence of PMPS, its predicting risk factors, and its impact on quality of life. Method. In this survey, 225 women completed a battery of questionnaires. The questionnaires comprised the short form of the McGill Pain Questionnaire (SF-MPQ) exploring the characteristics and the description of the pain, and a Short Form-36 (SF-36) Health Survey evaluating quality of life. Logistic regression analyses were subsequently performed to identify risk factors for PMPS. Results. 62 women (27.6%) reported PMPS as a consequence of surgery, and the pain was generally mild, mostly localized in breast area and intermittent. The pain was mainly described as aching (62.9%). 144 women reported sensory disturbance. We found that only the younger age is the predictive factor for PMPS (P < 0.05). Compared to the patients who did not experience PMPS, those who suffered from PMPS had significantly worse scores in role limitations due to physical problems (role physical, RP), body pain (BP), general health (GH), vitality (VT), role limitations due to emotional problems (role emotional, RE), and mental health (MH) (P < 0.05). Conclusion. PMPS is a significant problem, and the possible risk factors should be further explored. Patients with PMPS have significant worse quality of life, suggesting that patients should be well informed about the likelihood of experiencing the pain, and they may be afforded greater predictability and higher perceived control to enhance their quality of life.

Development of a screening instrument for risk factors of persistent pain after breast cancer surgery

Background:

Persistent postsurgical pain can have a significant effect on the quality of life of women being treated for breast cancer. The aim of this prospective study was to develop a screening tool to identify presurgical demographic, psychological and treatment-related factors that predict persistence of significant pain in the operated area after 6 months from surgery.

Methods:

Background and self-reported questionnaire data were collected the day before surgery and combined with treatment-related data. Pain in the operated area was assessed 6 months after surgery with a questionnaire. The Bayesian model was used for the development of a screening tool.

Results:

Report of preoperative chronic pain, more than four or more previous operations, preoperative pain in the area to be operated, high body mass index, previous smoking and older age were included in the six-factor model that best predicted significant pain at the follow-up in the 489 women studied.

Conclusion:

A six-factor risk index was developed to estimate the risk of developing significant pain after breast cancer surgery. Neither treatment- nor mood-related variables were included in the model. Identification of risk factors may lead to prevention of persistent postsurgery pain. This tool could be used for target prevention to those who are at the highest risk of developing persistent postsurgery pain.

Role of sigma-1 receptors in paclitaxel-induced neuropathic pain in mice

Sigma-1 (σ(1)) receptors play a role in different types of pain and in central sensitization mechanisms; however, it is unknown whether they are involved in chemotherapy-induced neuropathic pain. We compared the ability of paclitaxel to induce cold (acetone test) and mechanical (electronic Von Frey test) allodynia in wild-type (WT) and σ(1) receptor knockout (σ(1)-KO) mice. We also tested the effect on paclitaxel-induced painful neuropathy of BD-1063 (16-64 mg/kg, subcutaneously) and S1RA (32-128 mg/kg, subcutaneously), 2 selective σ(1) receptor antagonists that bind to the σ(1) receptor with high affinity and competitively. The responses to cold and mechanical stimuli were similar in WT and σ(1)-KO mice not treated with paclitaxel; however, treatment with paclitaxel (2 mg/kg, intraperitoneally, once per day during 5 consecutive days) produced cold and mechanical allodynia and an increase in spinal cord diphosphorylated extracellular signal-regulated kinase (pERK) in WT but not in σ(1)-KO mice. The administration of BD-1063 or S1RA 30 minutes before each paclitaxel dose prevented the development of cold and mechanical allodynia in WT mice. Moreover, the acute administration of both σ(1) receptor antagonists dose dependently reversed both types of paclitaxel-induced allodynia after they had fully developed. These results suggest that σ(1) receptors play a key role in paclitaxel-induced painful neuropathy.

PERSPECTIVE

Antagonists of the σ(1) receptor may have therapeutic value for the treatment and/or prevention of paclitaxel-induced neuropathic pain. This possibility is especially interesting in the context of chemotherapy-induced neuropathy, where the onset of nerve damage is predictable and preventive treatment could be administered.

Long-term follow-up of pain and emotional characteristics of women after surgery for breast cancer

CONTEXT

Persistent pain after treatment for breast cancer (PPBCT) is a common side effect of breast cancer treatment, with prevalence as high as 50%. It is predominantly a neuropathic condition.

OBJECTIVES

The aim of this cross-sectional, questionnaire-based study was to examine the emotional characteristics of patients with PPBCT in long-term breast cancer patients. A secondary objective was to characterize the risk factors and severity of that pain.

METHODS

From March 1, 2010 to April 9, 2010, long-term follow-up patients were invited to complete a questionnaire. This recorded their surgical and demographic data and ascertained whether they had PPBCT. If the patient had pain, she completed a range of validated self-report questionnaires and questions about the nature of the pain, including a visual analogue scale.

RESULTS

One hundred eleven patients completed the questionnaire; 33 (29.7%) patients reported chronic pain at a median time of 64 months postoperatively (interquartile range 54.25). Patients with persistent pain were not significantly more anxious (t(105)=-0.369, P=0.713) or depressed (t(105)=0.713, P=0.507) than patients without pain. Patients with constant pain compared with intermittent pain were significantly more anxious (t(25)=-3.460, P=0.002). Preoperative pain conferred a fivefold increased risk of PPBCT (odds ratio [OR]=5.17, 95% confidence interval [CI]=1.79-14.97, P=0.002); chemotherapy conferred a threefold increased risk (OR=3.004, 95% CI=1.22-7.40, P=0.017).

CONCLUSION

We have shown significant numbers of patients suffer from PPBCT. At a median time of 64.5 months, women with pain are not significantly more anxious or depressed than women without pain. Preoperative pain and chemotherapy have been highlighted as risk factors.

Selecting a comparison group for 5-year oral and pharyngeal cancer survivors: two methods

BACKGROUND

To assess potential long-term consequences of cancer treatment, studies that include comparison groups are needed. These comparison groups should be selected in a way that allows the subtle long-range effects of cancer therapy to be detected and distinguishes them from the effects of aging and other risk factors. The purpose of this investigation was to test two methods of recruiting a comparison group for 5-year oral and pharyngeal cancer survivors (peer-nominated and listed sample) with emphasis on feasibility and the quality of the match.

METHODS

Participants were drawn from a pool of 5-year survivors treated at a large Southeastern hospital. A peer-nominated sample was solicited from the survivors. A listed sample matched on sex, age, and zip code was purchased. Telephone interviews were conducted by a professional call center.

RESULTS

The following represent our key findings: The quality of matching between survivors and listed sample was better than that between survivors and peer-nominated group in age and sex. The quality of matching between the two methods on other key variables did not differ except for education, with the peer method providing a better match for the survivors than the listed sample. The yield for the listed sample method was greater than for the peer-nominated method. The cost per completed interview was greater for the peer-nominated method than the listed sample.

CONCLUSION

This study not only documents the methodological challenges in selecting a comparison group for studies examining the late effects of cancer treatment among older individuals but also documents challenges in matching groups that potentially have disproportionate levels of comorbidities and at-risk health behaviors.

Chemotherapy-induced neuropathic pain and its relation to cluster symptoms in breast cancer patients treated with paclitaxel

The majority of patients with breast cancer receiving chemotherapy report multiple symptoms. Compelling evidence has shown that subgroups of patients can be clustered by the severity of symptoms. Recent studies demonstrate that chemotherapy with such substances as paclitaxel can cause neuropathic pain (CINP) and consequently neural damage.

OBJECTIVES

the present study examined the relationship between symptom clusters and CINP among 40 patients with breast cancer. The study was based on 2 sessions conducted before and during paclitaxel treatment. In each session, neuropathic pain was assessed by the DN4 Questionnaire. In the second session, the Lee Fatigue Scale, the General Sleep Disturbance Scale, and the Center for Epidemiological Studies-Depression Scale were also administered, and the worst pain intensity was assessed. Using cluster analysis, 2 symptom clusters were identified on the basis of the severity of the 4 symptoms scores. Patients in the High Cluster (37%) experienced a high level of all symptoms, whereas patients in the Low Cluster (63%) experienced a low level of all symptoms. Twenty patients (50%) were diagnosed with CINP. A subgroup of patients (23%) from the High Cluster was identified as having CINP; 35% were in the Low Cluster and free of CINP. In conclusion, there appears to be a specific subgroup of patients with hypersensitive cancer who need greater attention to symptom management. Early detection of symptoms, together with careful dose selection and assessment of early stages in the development of neuropathic pain, are essential for preventing the simultaneous occurrence of severe multiple symptoms and CINP.

Chronic Post Surgical Pain

Chronic post-surgical pain (CPSP) is a recognised adverse consequence of surgery; surgery is common, therefore the population at risk is considerable.Putative risk factors for CPSP include genetic predisposition, demographic, clinical (pain history, type of surgery, anaesthesia, acute pain severity), and psychological factors (vulnerability vs resilience).Evidence of prevention is limited: long-term benefit from pre-emptive/perioperative analgesia has not been demonstrated consistently.Large scale prospective studies with detailed pre, intra and postoperative multifactorial assessments are required to refine understanding of the aetiology and prognosis of CPSP.