Explainable Machine Learning Model to Preoperatively Predict Postoperative Complications in Inpatients With Cancer Undergoing Major Operations.

PURPOSE: Preoperative prediction of postoperative complications (PCs) in inpatients with cancer is challenging. We developed an explainable machine learning (ML) model to predict PCs in a heterogenous population of inpatients with cancer undergoing same-hospitalization major operations. METHODS: Consecutive inpatients who underwent same-hospitalization operations from December 2017 to June 2021 at a single institution were retrospectively reviewed. The ML model was developed and tested using electronic health record (EHR) data to predict 30-day PCs for patients with Clavien-Dindo grade 3 or higher (CD 3+) per the CD classification system. Model performance was assessed using area under the receiver operating characteristic curve (AUROC), area under the precision recall curve (AUPRC), and calibration plots. Model explanation was performed using the Shapley additive explanations (SHAP) method at cohort and individual operation levels. RESULTS: A total of 988 operations in 827 inpatients were included. The ML model was trained using 788 operations and tested using a holdout set of 200 operations. The CD 3+ complication rates were 28.6% and 27.5% in the training and holdout test sets, respectively. Training and holdout test sets' model performance in predicting CD 3+ complications yielded an AUROC of 0.77 and 0.73 and an AUPRC of 0.56 and 0.52, respectively. Calibration plots demonstrated good reliability. The SHAP method identified features and the contributions of the features to the risk of PCs. CONCLUSION: We trained and tested an explainable ML model to predict the risk of developing PCs in patients with cancer. Using patient-specific EHR data, the ML model accurately discriminated the risk of developing CD 3+ complications and displayed top features at the individual operation and cohort level.

Outcomes of rectal cancer patients who refuse surgery after incomplete clinical response to neoadjuvant therapy.

BACKGROUND AND OBJECTIVES: Total mesorectal excision (TME) remains the standard of care for patients with rectal cancer who have an incomplete response to total neoadjuvant therapy (TNT). A minority of patients will refuse curative intent resection. The aim of this study is to examine the outcomes for these patients. METHODS: A retrospective cohort study of stage 1-3 rectal adenocarcinoma patients who underwent neoadjuvant chemoradiation therapy or TNT at a single institution. Patients either underwent TME, watch-and-wait protocol, or if they refused TME, were counseled and watched (RCW). Clinical outcomes and resource utilization were examined in each group. RESULTS: One hundred seventy-one patients (Male 59%) were included with a median surveillance of 43 months. Twenty-nine patients (17%) refused TME and had shortened overall survival (OS). Twelve patients who refused TME converted to a complete clinical response (cCR) on subsequent staging with a prolonged OS. 92% of these patients had a near cCR at initial staging endoscopy. Increased physician visits and testing was utilized in RCW and WW groups. CONCLUSION: A significant portion of patients convert to cCR and have prolonged OS. Lengthening the time to declare cCR may be considered in select patients, such as those with a near cCR at initial endoscopic staging.

Inositol for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis to Inform the 2023 Update of the International Evidence-based PCOS Guidelines.

CONTEXT: Insulin resistance is common in women with polycystic ovary syndrome (PCOS). Inositol may have insulin sensitizing effects; however, its efficacy in the management of PCOS remains indeterminate. OBJECTIVE: To inform the 2023 international evidence-based guidelines in PCOS, this systematic review and meta-analysis evaluated the efficacy of inositol, alone or in combination with other therapies, in the management of PCOS. DATA SOURCES: Medline, PsycInfo, EMBASE, All EBM, and CINAHL from inception until August 2022. STUDY SELECTION: Thirty trials (n = 2230; 1093 intervention, 1137 control), with 19 pooled in meta-analyses were included. DATA EXTRACTION: Data were extracted for hormonal, metabolic, lipids, psychological, anthropometric, reproductive outcomes, and adverse effects by 1 reviewer, independently verified by a second. DATA SYNTHESIS: Thirteen comparisons were assessed, with 3 in meta-analyses. Evidence suggests benefits for myo-inositol or D-chiro-inositol (DCI) for some metabolic measures and potential benefits from DCI for ovulation, but inositol may have no effect on other outcomes. Metformin may improve waist-hip ratio and hirsutism compared to inositol, but there is likely no difference for reproductive outcomes, and the evidence is very uncertain for body mass indexI. Myo-inositol likely causes fewer gastrointestinal adverse events compared with metformin; however, these are typically mild and self-limited. CONCLUSION: The evidence supporting the use of inositol in the management of PCOS is limited and inconclusive. Clinicians and their patients should consider the uncertainty of the evidence together with individual values and preferences when engaging in shared decision-making regarding the use of inositol for PCOS.

Time and Motion Studies to assess surgical productivity in cataract theatre lists within the National Health Service: Immediate Sequential Bilateral Cataract Surgery versus Delayed Sequential Bilateral Cataract Surgery.

BACKGROUND: To compare productivity of National Health Service cataract lists performing unilateral cataract (UC) surgery vs Immediate Sequential Bilateral Cataract Surgery (ISBCS). METHODS: Five 4-hour lists with ISBCS cases and five with UC were observed using time and motion studies (TMS). Individual tasks and timings of each staff member in theatre was recorded by two observers. All operations were performed by consultant surgeons under local anaesthesia (LA). RESULTS: Median number of eyes operated per 4-hour list was 8 (range 6-8) in the ISBCS group and 5 (5-7) in the UC group (p = 0.028). Mean total theatre time (defined as time between the entry of the first patient and the exit of the last patient from theatre) was 177.12 (SD 73.62) minutes in the ISBCS group and 139.16 (SD 47.73) minutes in the UC group (p = 0.36). Mean time to complete two consecutive unilateral cataract surgery operations was 48.71 minutes compared to 42.23 minutes for a single ISBCS case (13.30% time saved). Based on our collected TMS data, a possible 5 consecutive ISBCS cases and 1 UC (total 11 cataract surgeries) could be performed during a four-hour theatre session, with a theatre utilisation quotient of 97.20%, contrasting to nine consecutive UC, with a theatre utilisation quotient of 90.40%. DISCUSSION: Performing consecutive ISBCS cases under LA on routine cataract surgery lists can increase surgical efficiency. TMS are a useful way to investigate surgical productivity and test theoretical models for efficiency improvements.

Combined Liver and Colon Resection of Synchronous Colorectal Liver Metastases at a Quaternary Center.

INTRODUCTION: Existing literature on the safety of combined liver and colorectal resections for synchronous colorectal liver metastases is mixed. Using a retrospective review of our institutional data, we aimed to show that combined colorectal and liver resections for synchronous metastases is both feasible and safe in a quaternary center. METHODS: A retrospective review of combined resections for synchronous colorectal liver metastases at a quaternary referral center from 2015 to 2020 was completed. Clinicopathologic and perioperative data was collected. Univariate and multivariable analyses were performed to identify risk factors for major postoperative complications. RESULTS: One hundred one patients were identified, with 35 undergoing major liver resections ( ≥ 3 segments) and 66 undergoing minor liver resections. The vast majority of patients (94%) received neoadjuvant therapy. There was no difference in postoperative major complications (Clavien-Dindo grade 3+) between major and minor liver resections (23.9% versus 12.1%, P = 0.16). On univariate analysis, Albumin-Bilirubin (ALBI) score >1 (P < 0.05) was predictive of major complication. However, on multivariable regression analysis, no factor was associated with significantly increased odds of major complication. CONCLUSIONS: This work demonstrates that with thoughtful patient selection, combined resection for synchronous colorectal liver metastases can be safely performed at a quaternary referral center.

Long-term pelvic fracture and overall mortality risk after pelvic cancer and pelvic radiation.

BACKGROUND: The association of pelvic radiation with pelvic fracture risk has not been examined in prospective cohort settings with comprehensive fracture risk assessment, cancer-free comparison populations, and long-term follow-up. Our objective is to better characterize pelvic fracture and overall mortality risks in postmenopausal women participating in the Women's Health Initiative. METHODS: A total of 135 743 Women's Health Initiative participants aged 50 to 79 years enrolled from 40 US clinical centers from 1993 to 1998 who had entry Fracture Risk Assessment Tool scores were eligible. Outcomes included pelvic cancer diagnosis, pelvic fracture occurrence, and mortality. Cox proportional hazards regression models were used to examine associations of pelvic cancer and pelvic radiation with pelvic fracture and mortality risk. RESULTS: After 17.7 years (median) follow-up, 4451 pelvic cancers, 10 139 pelvic fractures, and 33 040 deaths occurred. In multivariable analyses, women with incident pelvic cancer, compared with women who remained pelvic cancer free, had higher pelvic fracture risk (hazard ratio [HR] = 1.26, 95% confidence interval [CI] = 1.11 to 1.43) and higher overall mortality risk (HR = 2.91, 95% CI = 2.77 to 3.05). Women with pelvic cancer treated with pelvic radiation, compared with women with pelvic cancer not treated with pelvic radiation, had higher pelvic fracture risk (HR = 1.98, 95% CI = 1.41 to 2.78) and higher overall mortality after pelvic cancer (HR = 1.32, 95% CI = 1.15 to 1.52). CONCLUSIONS: Postmenopausal women with pelvic cancer, especially those receiving pelvic radiation, are at higher pelvic fracture risk and higher overall mortality risk. As therapeutic advances have reduced cancer mortality, attention to and interventions for pelvic fracture prevention may be important in pelvic cancer survivors.

Tumor extent impacts survival benefit in minimally invasive colectomy for T4 colon cancer: A propensity matched national cohort analysis.

BACKGROUND: T4 colon cancers have been underrepresented in randomized trials comparing minimally invasive colectomy (MC) versus open colectomy (OC). Retrospective studies suggest improved survival with MC versus OC, but have not addressed the impact of tumor extent. METHODS: Using the National Cancer Database (NCDB), we analyzed patients undergoing colectomy for T4 colon adenocarcinoma from 2010 to 2014. Propensity score matching was performed between MC and OC patients. Tumor extent was defined by zones based on adjacent organ involvement. RESULTS: Of the 19 178 eligible patients, 6564 (34%) underwent MC. After matching, MC was associated with improved overall survival (hazard ratios: 0.71, 95% confidence interval: 0.67-0.76; median OS 59 vs. 42 months, p < 0.001). Compared to MC patients, those undergoing OC had: a higher margin positive rate (p = 0.009); lower median nodes examined (p < 0.001); a lower rate of adjuvant chemotherapy (p < 0.001); and a longer median time to chemotherapy (p < 0.001). Stratified survival analyses demonstrated that MC was associated with improved overall survival compared to OC in all zones except zone 3 and 4. CONCLUSIONS: Compared to OC, MC for T4 colon cancer is associated with improved oncologic outcomes when performed for zone 0-2 tumors. For, zone 3 and 4 tumors MC and OC have similar oncologic outcomes and patients should be cautiously selected.

Impact of cessation of regular cataract surgery during the COVID pandemic on the rates of posterior capsular rupture and post-operative cystoid macular oedema.

BACKGROUND/OBJECTIVES: During the COVID-19, elective cataract surgery (CS) was significantly curtailed. We investigated whether consequent reduction of micro-surgical skills practice might lead to higher operative complications. METHODS: Single-centre, electronic note review of consecutive patients undergoing CS during three periods: 1st February 2019 to 13th January 2020 (P1) prior to pandemic; 3rd June 2020 to 11th January 2021 after 1st lockdown (P2); and 25th January to 30th July 2021 (P3) after/during second lockdown. RESULTS: 2276 operations occurred during P1, 999 during P2, 846 during P3. During P1, posterior capsular rupture (PCR) rate was 1.67%, similar to P2 (1.30%, p = 0.54), but lower than P3 (3.55%, p = 0.002). There was no difference in PCR risk percentage scores between routine and PCR cases during P1 (1.90% vs 2.03%, p = 0.83), P2 (2% vs 2.18%, p = 0.18), or P3 (1.87% vs. 2.71%, p = 0.08). During P2 and P3, there was a higher rate of cystoid macular oedema (CMO) compared with P1 (4.9% and 6.86% vs. 1.93%, p = 0.0001), with no differences in proportion of diabetics or cases with CMO in combination with PCR. There was no difference in surgeons grade experiencing PCR. CONCLUSIONS: In P3 following 9 months of curtailed elective CS, PCR rates were increased across all surgeon grades, occurring in cases with similar risk percentage scores. CMO rates were increased during COVID and not related to proportion of diabetics or increased PCR rates. The reduction in elective CS during the pandemic was associated with more complications, perhaps due to attenuation of microsurgical skills.

Evaluation of Comparative Surveillance Strategies of Circulating Tumor DNA, Imaging, and Carcinoembryonic Antigen Levels in Patients With Resected Colorectal Cancer.

Importance: A circulating tumor DNA (ctDNA) assay (Signatera; Natera) has been marketed for use in the surveillance of resected colorectal cancer despite limited data supporting such practice. Objective: To compare a ctDNA assay with standard radiographic imaging and measurement of carcinoembryonic antigen (CEA) levels, per National Comprehensive Cancer Network guidelines, in the surveillance of resected colorectal cancer. Design, Setting, and Participants: This retrospective, single-center cohort study evaluated surveillance strategies of ctDNA, imaging, and measurement of CEA levels in patients with resected colorectal cancer from September 1, 2019, to November 30, 2021. Main Outcomes and Measures: The sensitivity and specificity of ctDNA, imaging, measurement of CEA levels, and combination of imaging plus measurement of CEA levels in detecting a confirmed recurrence of colorectal disease. A confirmed recurrence was defined as a positive ctDNA finding or a finding on imaging confirmed by biopsy, CEA level elevation, or subsequent tumor radiographic dynamics. Results: A total of 48 patients with curatively resected colorectal cancer satisfied the inclusion criteria for this study (28 men [58.3%]; median age, 60 [IQR, 34-85] years) and underwent surveillance by ctDNA, imaging, and measurement of CEA levels. Fifteen patients had disease recurrence during surveillance. Positive ctDNA findings confirmed disease recurrence in 8 patients; imaging, in 9 patients; CEA levels, in 3 patients; and combined imaging plus CEA levels, in 11 patients. Numerically, ctDNA did not perform better than imaging in detecting recurrence, with sensitivities of 53.3% (95% CI, 27.4%-77.7%) and 60.0% (95% CI, 32.9%-82.5%), respectively (P > .99). The combination of imaging plus measurement of CEA levels (sensitivity, 73.3% [95% CI, 44.8%-91.1%]) had a numerical advantage compared with ctDNA in identifying recurrence (P = .55). In addition, no significant difference was noted among ctDNA (median, 14.3 months), imaging (median, 15.0 months), or imaging plus measurement of CEA levels (median, 15.0 months) in the time to identify disease recurrence. Conclusions and Relevance: The findings of this cohort study suggest that ctDNA assay may not provide advantages as a surveillance strategy compared with standard imaging combined with CEA levels when performed per National Comprehensive Cancer Network guidelines.

Cholecystectomy in patients with hematologic malignancies.

BACKGROUND: Cholecystectomy in patients with hematologic malignancies remains poorly understood. METHODS: We retrospectively evaluated patients with hematologic malignancies who underwent cholecystectomy at a single institution. RESULTS: Of 313 patients who presented for evaluation of abdominal pain, 64 underwent cholecystectomy for acute cholecystitis (34.4%), gangrenous cholecystitis (21.9%), chronic cholecystitis (23.4%), and cholelithiasis (20%). Most had a history of hematopoietic cell transplantation (62.5%) and/or immunosuppressive medication within 30 days of consultation (82.8%). Ultrasound had a 39% false-negative rate for acute nongangrenous cholecystitis. Operative time was 92 ± 39 min, 7 were performed open, 10 had intraoperative transfusions, and 4 had grade 3+ complications. Intraoperative transfusion was associated with increased postoperative length of stay (p = 0.03). Open procedure, operative time, estimated blood loss, intraoperative transfusion, and complications were not associated with timing of surgery. CONCLUSIONS: Patients with hematologic malignancies can safely undergo cholecystectomy. Length of postoperative stay for inpatients is associated with intraoperative blood transfusion.

Shear wave versus strain elastography of breast lesions-The value of incorporating boundary tissue assessment.

PURPOSE: This prospective study compares the diagnostic performance of strain elastography (SE) based on the elastogram to B-mode (E/B) size ratio to shear-wave elastography (SWE) incorporating assessment of boundary tissue stiffness. METHODS: In this prospective study, 81 women consented to undergo ultrasound (US) elastographic assessment prior to biopsy of their mass(es). A total of 101 masses were evaluated with SE and SWE using a single machine (Siemens Acuson S2000). The histopathologic diagnosis was used as the reference standard. The sensitivity, specificity and area under curve (AUC) were obtained for SE and SWE. RESULTS: The sensitivity and specificity of SE using the E/B ratio was 94.7% (95% CI: 87.6 100) and 81.0% (95% CI: 71.3 90.1) respectively. For SWE the sensitivity and specificity was 73.7% (95% CI: 59.7 87.7) and 82.5% (95% CI: 73.2 91.9) respectively. The AUC for SE was higher (0.878) compared to SWE (0.697). CONCLUSION: SE elastography using the E/B ratio yields diagnostic performance which is superior to SWE incorporating assessment of peripheral stiffness.

Sidedness determines clinical characteristics and survival outcomes in medullary adenocarcinoma of the colon.

Colon medullary adenocarcinoma (MAC) is a rare histologic subtype. Clinical presentation and cancer outcomes of MAC, compared to colon adenocarcinoma (AC), remain incompletely described. Annual age-adjusted incidence rates were computed using Surveillance, Epidemiology, and End Results (2002-2017). A cohort analysis using the National Cancer Database (2010-2016) compared patient characteristics in an unmatched dataset and prognostic characteristics in a 1:1 matched subset. Reported annual age-adjusted incidence of MAC has significantly increased, with an average annual percent change (APC) increase of 23.8% (95% CI: 19.2-28.6); concurrent AC incidence declined (APC: - 2.8, 95% CI: - 3.1 to - 2.8). Analyses of 1018 MAC and 210,784 AC unmatched patients showed that MAC patients were more often older, female, and white, with higher disease stage, poorly-differentiated tumors, right-sided laterality, and lymphovascular invasion (all p < 0.0001). Among those with known microsatellite status, instability was more prevalent among MAC than AC patients (82% vs. 24%, p < 0.0001). Multivariate analyses of the matched dataset revealed that MAC histology was not independently associated with overall survival. However, when stratifying by laterality, left-sided MAC was associated with shorter survival when compared to right-sided MAC (HR 1.66, 95% CI 1.16-2.38) and right-sided AC (HR 1.54, 95% CI 1.12-2.12). The reported incidence of MAC is increasing, in contrast to the declining incidence of AC. MAC clinical and molecular features are distinct from AC and likely account for outcome differences. Overall, left-sided MAC was associated with the shortest OS. Molecular profiling may improve treatment guidelines for MAC.

Subungual Melanoma: A Single Institution Experience.

Despite the changing paradigms of melanoma treatment in recent years, there remains a relative paucity of data regarding subungual melanoma in the literature. From 2002-2018, 25 patients with subungual melanoma were surgically treated at our facility. A retrospective chart review was conducted to collect relevant demographic, clinical, pathologic, and outcomes data. The median age at diagnosis was 69 years. Most patients (60%) were male, and the melanoma lesion was most often located on the foot (68%). Acral-lentiginous was the most common histologic subtype (59%), and the median Breslow thickness was 3.4 mm. Fifteen patients (63%) underwent a sentinel lymph node biopsy as part of their surgical resection, and four of these patients (27%) had metastatic disease in the lymph nodes. In total, 10 patients underwent lymph node dissection of the involved basin. The median follow up was 21 months in this patient population. Age, gender, tumor location, ulceration, and lesion histology were not significantly associated with recurrence free survival (RFS). Increasing Breslow thickness was found to be significantly associated with shorter RFS (HR: 1.07, CI: 1.03-1.55). In total, 13 patients developed a disease recurrence, and RFS rates were 66% at 1 year and 40% at 3 years. Additionally, 91 and 37% of patients were alive at one year and three years, respectively. Subungual melanomas are rare lesions that often have a more advanced stage at diagnosis, which contributes to the poor prognosis of these cutaneous malignancies.

Photoacoustic Computed Tomography of Breast Cancer in Response to Neoadjuvant Chemotherapy.

Neoadjuvant chemotherapy (NAC) has contributed to improving breast cancer outcomes, and it would ideally reduce the need for definitive breast surgery in patients who have no residual cancer after NAC treatment. However, there is no reliable noninvasive imaging modality accepted as the routine method to assess response to NAC. Because of the inability to detect complete response, post-NAC surgery remains the standard of care. To overcome this limitation, a single-breath-hold photoacoustic computed tomography (SBH-PACT) system is developed to provide contrast similar to that of contrast-enhanced magnetic resonance imaging, but with much higher spatial and temporal resolution and without injection of contrast chemicals. SBH-PACT images breast cancer patients at three time points: before, during, and after NAC. The analysis of tumor size, blood vascular density, and irregularity in the distribution and morphology of the blood vessels on SBH-PACT accurately identifies response to NAC as confirmed by the histopathological diagnosis. SBH-PACT shows its near-term potential as a diagnostic tool for assessing breast cancer response to systemic treatment by noninvasively measuring the changes in cancer-associated angiogenesis. Further development of SBH-PACT may also enable serial imaging, rather than the use of current invasive biopsies, to diagnose and follow indeterminate breast lesions.

Local excision and chemoradiation for clinical node-negative anal adenocarcinoma.

BACKGROUND: Given the lack of consensus in the surgical treatment of anal adenocarcinoma, practice-patterns demonstrate utilization of organ-preserving techniques. The adequacy of local excision compared to abdominoperineal resection (APR) as a surgical approach for stage II disease is unknown. Our study examines the utilization of local excision in the treatment of stage II anal adenocarcinoma, rates of R0 resection, and differences in overall survival compared to APR. MATERIALS AND METHODS: Using the National Cancer Database (2004-2016), we retrospectively analyzed patients diagnosed with clinical stage II anal adenocarcinoma who received chemoradiation and surgery. Patient cohorts were assigned based on the surgical procedure they received. Propensity score matching was used to offset selection bias and confounding factors. Treatment approach, pathologic margin status, and overall survival were assessed. RESULTS: Overall, 359 patients underwent resection of clinical stage II anal adenocarcinoma and received chemoradiation therapy. Of these patients, 87 (24%) underwent local excision, whereas 272 (76%) received an abdominoperineal resection. In a propensity score-matched cohort, patients who underwent local excision were less likely to achieve an R0 resection (40% vs 90%), and more likely to receive adjuvant instead of neoadjuvant chemoradiation. Overall survival was not significantly different between the propensity-matched groups. Surgical approach and pathologic margin status were not independently associated with overall survival. CONCLUSIONS: Among patients with clinical stage II anal adenocarcinoma who received chemotherapy and radiation, complete resection was significantly less likely with local excision compared to abdominoperineal resection, however, overall survival was not affected. Prospective studies of neoadjuvant chemoradiation followed by local excision are warranted.

A preliminary prospective study of health-related quality of life among Chinese-American breast cancer survivors.

PURPOSE: This study examined the predictors of health-related quality of life (HRQOL) and changes in HRQOL over a 1-year period among Chinese-American breast cancer survivors (BCS). METHODS: A two-wave longitudinal research design included participants from hospital-based cancer registries and community organizations in Los Angeles. Participants completed mailed questionnaires at baseline and 12-month follow-up. HRQOL was measured using the Functional Assessment of Cancer Therapy-General (FACT-G v.4). Change in HRQOL was assessed using a 7-point meaningful change score. RESULTS: Participants were 73 Chinese-American BCS, a majority of whom were middle-aged (M = 54.6, SD = 9.2), lower income (63% < 45K), and diagnosed with stage I-II (83%) breast cancer. Regression analyses showed that multilevel contextual factors including general health perception, quality of care, life stress, and improvement in general health perception significantly predicted HRQOL at baseline and follow-up. The final model explained 72% of the variance of HRQOL. The examination of meaningful change indicated that improvement was reported by 32% (n = 22) and deterioration by 25% (n = 17); the majority indicated minimal change (43%, n = 30). Improvement was associated with increases in family communication, social support, and general health perception, while deterioration was associated with declines in social support, family communication, and general health perception. CONCLUSION: Findings indicate that among Chinese-American BCS, HRQOL is influenced by socioecological factors such as family communication and life stress. Results suggest that cancer survivorship outcomes research may benefit from theoretical foundations that examine the broader contextual dimensions that seem to impact and predict HRQOL. Implications for research are discussed.

Raman spectroscopy and artificial intelligence to predict the Bayesian probability of breast cancer.

This study addresses the core issue facing a surgical team during breast cancer surgery: quantitative prediction of tumor likelihood including estimates of prediction error. We have previously reported that a molecular probe, Laser Raman spectroscopy (LRS), can distinguish healthy and tumor tissue. We now report that combining LRS with two machine learning algorithms, unsupervised k-means and stochastic nonlinear neural networks (NN), provides rapid, quantitative, probabilistic tumor assessment with real-time error analysis. NNs were first trained on Raman spectra using human expert histopathology diagnostics as gold standard (74 spectra, 5 patients). K-means predictions using spectral data when compared to histopathology produced clustering models with 93.2-94.6% accuracy, 89.8-91.8% sensitivity, and 100% specificity. NNs trained on k-means predictions generated probabilities of correctness for the autonomous classification. Finally, the autonomous system characterized an extended dataset (203 spectra, 8 patients). Our results show that an increase in DNA|RNA signal intensity in the fingerprint region (600-1800 cm-1) and global loss of high wavenumber signal (2800-3200 cm-1) are particularly sensitive LRS warning signs of tumor. The stochastic nature of NNs made it possible to rapidly generate multiple models of target tissue classification and calculate the inherent error in the probabilistic estimates for each target.

Feasibility of Remote Occupational Therapy Services via Telemedicine in a Breast Cancer Recovery Program.

IMPORTANCE: Access to perioperative breast surgery occupational therapy services remains limited in remote areas. OBJECTIVE: To assess the feasibility and acceptance of occupational therapy services using a "hub-and-spoke" telemedicine model. DESIGN: Prospective study using videoconferencing to connect the occupational therapist, located at the hub site, with the patient, located at the spoke site. SETTING: National Cancer Institute Comprehensive Cancer Center (hub site) and affiliated community cancer center (spoke site). The sites are 75 mi apart. PARTICIPANTS: Female breast cancer patients (N = 26) scheduled for breast surgery were asked to participate in telemedicine occupation therapy sessions. Patients lived in a geographically remote region and travelled a mean of 16 miles (range = 3-85) to the hub site. The majority (56%) of the patients had public insurance. INTERVENTION: Perioperative occupational therapy sessions completed through videoconferencing. OUTCOMES AND MEASURES: Outcome measures were participation in and completion rate for the sessions, number of sessions required to return to baseline, and time interval from surgery to return to baseline function. Patient satisfaction was assessed with a questionnaire. RESULTS: Of the patients who enrolled in the study, 18 completed all postoperative sessions in which functional assessments, exercises, and education were provided. Patients regained baseline function within a mean of 42.4 days after surgery and after an average of three sessions. Patients reported high satisfaction with the sessions. CONCLUSIONS AND RELEVANCE: Videoconference telemedicine in breast perioperative rehabilitation is feasible, effective, and acceptable to patients. This study adds to the emerging use of telemedicine for rehabilitative services. WHAT THIS ARTICLE ADDS: This study, by demonstrating the acceptability, practicality, and efficacy of breast perioperative occupational therapy services offered through a videoconferencing platform, supports continued research to evaluate the value of telemedicine. Issues with access to medical care may be mitigated through creative use of technology.