Fifty years of bone tumors.

There have been enormous advances in the treatment of bone tumors over the past half-century. The most notable of these has been the transition from amputation as the standard of care to limb salvage surgery. This transition is the result of advances in imaging techniques, accurate diagnosis, systemic therapies (including chemotherapy), and prosthetic design for the reconstruction of musculoskeletal defects. Advances have also been made in the management of benign and metastatic bone tumors.

The critical difference in the DASH (Disabilities of the Arm, Shoulder, and Hand) outcome measure after essential upper extremity tumor surgery.

BACKGROUND: The DASH (Disabilities of the Arm, Shoulder, and Hand) is a scored questionnaire that is widely used to evaluate the health-related quality of life of patients with upper limb musculoskeletal disorders. However, numerical changes in the measure scores lack clinical significance without meaningful threshold change values of outcome measures that are diagnostically specific. The minimal clinically important difference (MCID) is useful for the interpretation of scores by defining the smallest change that a patient would perceive. However, the MCIDs of the scores in orthopedic oncology patients has not been reported. We aimed to determine the MCIDs of the measure in orthopedic oncology patients. METHODS: Data from our health-related quality of life database from 1999 to 2005 were retrospectively reviewed after institutional review board approval. Seventy-eight patients who underwent surgery and completed 2 surveys during postoperative follow-up were evaluated. Two different methods were used to estimate the MCIDs: distribution-based and anchor-based approaches (the latter used receiver operating characteristic analysis). RESULTS: Using distribution-based methods, the MCIDs of the DASH questionnaire were 7.4 and 8.3 by half standard deviation and the 90% interval of minimal detectable change, respectively. By anchor-based method (receiver operating characteristic analysis), the MCID was 8.3. CONCLUSION: The MCID values calculated by each method validates that the results for upper extremity oncology patients were similar to those reported in other orthopedic conditions. These results identify the threshold for meaningful improvements in DASH scores in orthopedic oncology patients and establish the reference to evaluate health-related quality of life and the outcomes of upper extremity oncology surgery. These data should be further refined for disease- and reconstruction-specific analyses.

Association between patient age and the risk of mortality following local recurrence of a sacral chordoma.

BACKGROUND: Local recurrence (LR) of sacral chordoma is a difficult problem and the mortality risk associated with LR remains poorly described. The purpose of this study was to evaluate the risk of mortality in patients with LR and determine if patient age is associated with mortality. METHODS: A total of 218 patients (144 male, 69 female; mean age 59 ± 15 years) with sacrococcygeal chordomas were reviewed. Cumulative incidence functions and competing risks for death due to disease and nondisease mortality were employed to analyze mortality trends following LR. RESULTS: The 10-year overall survival (OS) was 55%. Patients with LR had 44% 10-year OS, similar to patients without (59%; P = .38). The 10-year OS between those less than 55 compared with ≥55 years were similar (69% vs 48%; P = .52). The 10-year death due to disease was worse in patients with LR compared with those without (44% vs 84%; P < .001). In patients without LR, patients ≥55 years were 1.6-fold more likely to experience death due to other causes. CONCLUSIONS: Patients with an LR are more likely to die due to disease. Advanced patient age was associated with higher all-cause mortality following resection of sacral chordoma. LR of chordoma was associated with increased disease-specific mortality, regardless of age.

What Are the Minimum Clinically Important Differences in SF-36 Scores in Patients with Orthopaedic Oncologic Conditions?

BACKGROUND: The SF-36 is widely used to evaluate the health-related quality of life of patients with musculoskeletal tumors. The minimum clinically important difference (MCID) is useful for interpreting changes in functional scores because it defines the smallest change each patient may perceive. Since the MCID is influenced by the population characteristics, MCIDs of the SF-36 should be defined to reflect the specific conditions of orthopaedic oncology patients. QUESTIONS/PURPOSES: (1) What is the MCID of SF-36 physical component summary (PCS) and mental component summary (MCS) scores in patients with orthopaedic oncologic conditions when calculated with distribution-based methods? (2) What is the MCID of SF-36 PCS and MCS scores in patients with orthopaedic oncologic conditions when calculated by anchor-based methods? METHODS: Of all 960 patients who underwent surgery from 1999 to 2005, 32% (310) of patients who underwent musculoskeletal oncologic surgery and completed two surveys during postoperative follow-up were reviewed. We evaluated a dataset that ended in 2005, completing follow-up of data accrued as part of the cooperative effort between the American Academy of Orthopaedic Surgeons and the Council of Musculoskeletal Specialty Societies to create patient reported quality of life instruments for lower extremity conditions. This effort, started in 1994 was validated and widely accepted by its publication in 2004. We believe the findings from this period are still relevant today because (1) this critical information has never been available for clinicians and researchers to distinguish real differences in outcome among orthopaedic oncology patients, (2) the SF-36 continues to be the best validated and widely used instrument to assess health-related quality of life, and unfortunately (3) there has been no significant change in outcome for oncology patients over the intervening years. SF-36 PCS and MCS are aggregates of the eight scale scores specific to physical and mental dimension (scores range from 0 to 100, with higher scores representing better health). Their responsiveness has been shown postoperatively for several surgical procedures (such as, colorectal surgery). Two different methods were used to calculate the MCID: the distribution-based method, which was based on half the SD of the change in score and standard error of the measurement at baseline, and anchor-based, in which a receiver operating characteristic (ROC) curve analysis was performed. The anchor-based method uses a plain-language question to ask patients how their individual conditions changed when compared with the previous survey. Answer choices were "much better," "somewhat better," "about the same," "somewhat worse," or "much worse." The ROC curve-derived MCIDs were defined as the change in scores from baseline, with sensitivity and specificity to detect differences in patients who stated their outcome was, about the same and those who stated their status was somewhat better or somewhat worse. This approach is based on each patient's perception. It considers that the definition of MCID is the minimal difference each patient can perceive as meaningful. RESULTS: Using the distribution-based method, we found that the MCIDs of the PCS and MCS were 5 and 5 by half the SD, and 6 and 5 by standard error of the measurement. In the anchor-based method, the MCIDs of the PCS and MCS for improvement/deterioration were 4 (area under the curve, 0.82)/-2 (area under the curve, 0.79) and 4 (area under the curve, 0.72)/ (area under the curve, 0.68), respectively. CONCLUSIONS: Since both anchor-based and distribution-based MCID estimates of the SF-36 in patients with musculoskeletal tumors were so similar, we have confidence in the estimates we made, which were about 5 points for both the PCS and the MCS subscales of the SF-36. This suggests that interventions improving SF-36 by less than that amount are unlikely to be perceived by patients as clinically important. Therefore, those interventions may not justify exposing patients to risk, cost, or inconvenience. When applying new interventions to orthopaedic oncology patients going forward, it will be important to consider these MCIDs for evaluation purposes. LEVEL OF EVIDENCE: Level III, diagnostic study.

Treatment of dedifferentiated chordoma: a retrospective study from a large volume cancer center.

OBJECTIVE: Dedifferentiated chordomas (DC) are genetically and clinically distinct from conventional chordomas (CC), exhibiting frequent SMARCB1 alterations and a more aggressive clinical course. We compared treatment and outcomes of DC and CC patients in a retrospective cohort study from a single, large-volume cancer center. METHODS: Overall, 11 DC patients were identified from 1994 to 2017 along with a cohort of 68 historical control patients with CC treated during the same time frame. Clinical variables and outcomes were collected from the medical record and Wilcoxon rank sum or Fisher exact tests were used to make comparisons between the two groups. Kaplan-Meier survival analysis and log-rank tests were used to compare DC and CC overall survival. RESULTS: DC demonstrated a bimodal age distribution at presentation (36% age 0-24; 64% age > 50). DC patients more commonly presented with metastatic disease than CC patients (36% vs. 3% p = 0.000). DC patients had significantly shorter time to local treatment failure after radiation therapy (11.1 months vs. 34.1 months, p = 0.000). The rate of distant metastasis following treatment was significantly higher in DC compared to CC (57% vs. 5%, p = 0.000). The median overall survival after diagnosis for DC was 20 months (95% CI 0-48 months) compared to 155 months (95% CI 94-216 months) for CC (p = 0.007). CONCLUSION: DC patients exhibit significantly higher rates of both synchronous and metachronous metastases, as well as shorter overall survival rates compared to conventional chordoma. The relatively poor survival outcomes with conventional therapies indicate the need to study targeted therapies for the treatment of DC.

Low dose radiotherapy is associated with local complications but not disease control in sacral chordoma.

BACKGROUND: We reviewed the disease control and complications of the treatment of sacrococcygeal chordoma from four tertiary cancer centers with emphasis on the effects of radiotherapy in surgically treated patients. METHODS: A total of 193 patients with primary sacrococcygeal chordoma from 1990 to 2015 were reviewed. There were 124 males, with a mean age of 59 ± 15 years and a mean follow-up of 7 ± 4 years. Eighty-nine patients received radiotherapy with a mean total dose of 61.8 ± 10.9 Gy. RESULTS: The 10-year disease-free and disease-specific survival was 58% and 72%, respectively. Radiation was not associated with local recurrence (hazard ratio [HR], 1.13; 95% confidence interval [CI], 0.59-2.17; P = 0.71), metastases (HR, 0.93; 95% CI, 0.45-1.91; P = 0.85) or disease-specific survival (HR, 0.96; 95% CI, 0.46-2.00; P = 0.91). Higher doses (≥70 Gy; HR, 0.52; 95% CI, 0.20-1.32; P = 0.17) may be associated with reduced local recurrence. Radiotherapy was associated with wound complications (HR, 2.76; 95% CI, 1.64-4.82;, P < 0.001) and sacral stress fractures (HR, 4.73; 95% CI, 1.88-14.38; P < 0.001). CONCLUSIONS: In this multicenter review, radiotherapy was not associated with tumor outcome but associated with complications. The routine use of radiotherapy with en-bloc resection of sacrococcygeal chordomas should be reconsidered in favor of a selective, individualized approach with a radiation dose of ≥70 Gy.

Chemotherapy Curtails Bone Formation From Compliant Compression Fixation of Distal Femoral Endoprostheses.

BACKGROUND: Modulated compliant compressive forces may contribute to durable fixation of implant stems in patients with cancer who undergo endoprosthetic reconstruction after tumor resection. Chemotherapy effects on bone hypertrophy and osteointegration have rarely been studied, and no accepted radiologic method exists to evaluate compression-associated hypertrophy. QUESTIONS/PURPOSES: (1) What was the effect of chemotherapy on the newly formed bone geometry (area) at 1 year and the presumed osteointegration? (2) What clinical factors were associated with the degree of hypertrophy? (3) Did the amount of bone formation correlate with implant fixation durability? (4) Was the amount of new bone generation or chemotherapy administration correlated with Musculoskeletal Tumor Society (MSTS) score? METHODS: Between 1999 and 2013, we performed 245 distal femoral reconstructions for primary or revision oncologic indications. We evaluated 105 patients who received this implant. Ten were excluded because they lacked 2 years of followup and two were lost to followup, leaving 93 patients for review. All underwent distal femur reconstruction with the compliant compressive fixation prosthesis; 49 received postoperative chemotherapy and 44 did not. During this period, the implant was used for oncology patients < 60 years of age without metastases and with > 8 cm of intact, nonirradiated bone distal to the lesser trochanter and ≥ 2.5 mm of cortex. Our cohort included patients with painful loosening of cemented or uncemented stemmed femoral megaprostheses when revision with the compliant compressive device was feasible. Patients with high-grade sarcomas all received chemotherapy, per active Children's Oncology Group protocols, for their tumor diagnosis. At each imaging time point (3, 6, 9, 12, 18, 24 months), we measured the radiographic area of the bone under compression using National Institutes of Health open-access software, any shortening of the spindle-anchor plug segment distance as reflected by the exposed traction bar length, and prosthesis survivorship. Clinical and functional status and MSTS scores were recorded at each followup visit. Duration of prosthesis retention without aseptic loosening or mechanical failure was evaluated using Kaplan-Meier analysis, censoring patients at last followup. RESULTS: Chemotherapy was associated with the amount of overall bone formation in a time-dependent fashion. In the 12 months after surgery there was more bone formation in patients who did not receive postoperative chemotherapy than those who did (60.2 mm, confidence interval [CI] 49.3-71.1 versus 39.1, CI 33.3-44.9; p = 0.001). Chemotherapy was not associated with prosthesis survival. Ten-year implant survival was 85% with chemotherapy and 88% without chemotherapy (p = 0.74). With the number of patients we had, we did not identify any clinical factors that were associated with the amount (area) of hypertrophy. The hypertrophied area was not associated with the durability of implant fixation. MSTS scores were lower in patients treated with chemotherapy (25 versus 28; p = 0.023), but were not correlated with new bone formation. CONCLUSIONS: The relationships among chemotherapy, bone formation, and prosthetic survivorship are complex. Because bone formation is less in the first year when the patient is being treated with chemotherapy, it is not clear if the rehabilitation schedule should be different for those patients receiving chemotherapy compared with those who do not. The relationship between early bone formation and the timing of weightbearing rehabilitation should be evaluated in a multicenter study. LEVEL OF EVIDENCE: Level III, therapeutic study.

Should the Use of Biologic Agents in Patients With Renal and Lung Cancer Affect Our Surgical Management of Femoral Metastases?

BACKGROUND: Biologic agents may prolong survival of patients with certain kidney and lung adenocarcinomas that have metastasized to bone, and patient response to these agents should be considered when choosing between an endoprosthesis and internal fixation for surgical treatment of femoral metastases. QUESTIONS/PURPOSES: Among patients undergoing surgery for femoral metastases of lung or renal cell carcinoma, (1) Does survival differ between patients who receive only cytotoxic chemotherapy and those who either respond or do not respond to biologic therapy? (2) Does postsurgical incidence of local disease progression differ between groups stratified by systemic treatment and response? (3) Does implant survival differ among groups stratified by systemic treatment and response? METHODS: From our institutional longitudinally maintained orthopaedic database, patients were identified by a query initially identifying all patients who carried a diagnosis of renal cell carcinoma or lung carcinoma. Patients who underwent internal fixation or prosthetic reconstruction between 2000 and 2016 for pathologic fracture of the femur and who survived ≥ 1 year after surgery were studied. Patients who received either traditional cytotoxic chemotherapy or a biologic agent were included. Patients were classified as responders or nonresponders to biologic agents based on whether they had clinical and imaging evidence of a response recorded on two consecutive office visits over ≥ 6 months. Endpoints were overall survival from the time of diagnosis, survival after the femoral operation, evidence of disease progression in the femoral operative site, and symptomatic local disease progression for which revision surgery was necessary. Our analysis included 148 patients with renal (n = 26) and lung (n = 122) adenocarcinoma. Fifty-one patients received traditional chemotherapy only. Of 97 patients who received a biologic agent, 41 achieved a response (stabilization/regression of visceral metastases), whereas 56 developed disease progression. We analyzed overall patient survival with the Kaplan-Meier method and used the log-rank test to identify significant differences (p < 0.05) between groups. RESULTS: One-year survival after surgery among patients responsive to biologic therapy was 61% compared with 20% among patients nonresponsive to biologics (p < 0.001) and 10% among those who received chemotherapy only (p < 0.009). With the number of patients we had to study, we could not detect any difference in local progression of femoral disease associated with systemic treatment and response. Radiologic evidence of periimplant local disease progression developed in three (7%) of 41 patients who responded to biologic treatment, two (3%) of 56 patients nonresponsive to biologics, and one (2%) of 51 patients treated with traditional chemotherapy. With the numbers of patients we had, we could not detect a difference in patients who underwent revision. All three patients responsive to biologics who developed local recurrence underwent revision, whereas the two without a response to biologics did not. CONCLUSIONS: Biologic therapy improves the overall longevity of some patients with lung and renal metastases to the femur in whom a visceral disease response occurred. In our limited cohort, we could not demonstrate an implant survival difference between such patients and those with shorter survival who may have had more aggressive disease. However, an increased life expectancy beyond 1 year among patients responsive to biologics may increase risk of mechanical failure of fixation constructs. LEVEL OF EVIDENCE: Level III, therapeutic study.

Retrospective Review of Atypical Femoral Fracture in Metastatic Bone Disease Patients Receiving Denosumab Therapy.

BACKGROUND: Denosumab therapy is used to reduce skeletal-related events in metastatic bone disease (MBD). There have been reports of atypical femoral fracture (AFF) in osteoporotic patients treated with denosumab but none in the context of higher dose and more frequent denosumab therapy for MBD. The goal of this study was to assess the incidence of AFF in MBD. PATIENTS AND METHODS: We conducted a retrospective review of 253 patients who received a minimum of 12 doses of denosumab at 120 mg each for MBD. To identify patients with asymptomatic atypical stress reactions in the lateral subtrochanteric femur (which precede fractures), we reviewed the skeletal images of 66 patients who had received at least 21 doses of denosumab for AFF features. RESULTS: These patients received a median of 17 doses, with a median treatment duration of 23 months. There was 1 case of undiagnosed clinical AFF detected after chart review and 2 cases of subclinical atypical femoral stress reaction observed on imaging review after 23 doses of denosumab over 33 months, 28 doses over 27 months, and 21 doses over 21 months, respectively. Scout computed tomography films showed diffuse cortical thickening of diaphysis with localized periosteal reaction of lateral femoral cortex. Bone scan and magnetic resonance imaging scan of 2 patients with stress reactions confirmed the diagnosis. CONCLUSION: The incidence of clinical AFF in this context is 0.4% (1/253; 95% confidence interval [CI] 0.1%-2.2%), and the incidence of atypical femoral stress reaction based on imaging review is 4.5% (3/66; 95% CI 1.6%-12.5%). Clinicians should be aware of the clinical prodrome (which may or may not be present) and antecedent imaging changes associated with AFF. The Oncologist 2017;22:438-444Implications for Practice: Among patients with metastatic bone disease treated with denosumab, cases of clinical and subclinical atypical femoral fracture (AFF) are rare. The one detected case of clinical fracture went unrecognized despite prodromic symptoms. Clinicians should be aware of (a) the potential prodrome of anterior thigh/groin pain and (b) subclinical imaging changes in the lateral femur, both of which may precede clinical AFF.

Can We Estimate Short- and Intermediate-term Survival in Patients Undergoing Surgery for Metastatic Bone Disease?

BACKGROUND: Objective means of estimating survival can be used to guide surgical decision-making and to risk-stratify patients for clinical trials. Although a free, online tool ( www.pathfx.org ) can estimate 3- and 12-month survival, recent work, including a survey of the Musculoskeletal Tumor Society, indicated that estimates at 1 and 6 months after surgery also would be helpful. Longer estimates help justify the need for more durable and expensive reconstructive options, and very short estimates could help identify those who will not survive 1 month and should not undergo surgery. Thereby, an important use of this tool would be to help avoid unsuccessful and expensive surgery during the last month of life. QUESTIONS/PURPOSES: We seek to provide a reliable, objective means of estimating survival in patients with metastatic bone disease. After generating models to derive 1- and 6-month survival estimates, we determined suitability for clinical use by applying receiver operator characteristic (ROC) (area under the curve [AUC] > 0.7) and decision curve analysis (DCA), which determines whether using PATHFx can improve outcomes, but also discerns in which kinds of patients PATHFx should not be used. METHODS: We used two, existing, skeletal metastasis registries chosen for their quality and availability. Data from Memorial Sloan-Kettering Cancer Center (training set, n = 189) was used to develop two Bayesian Belief Networks trained to estimate the likelihood of survival at 1 and 6 months after surgery. Next, data from eight major referral centers across Scandinavia (n = 815) served as the external validation set-that is, as a means to test model performance in a different patient population. The diversity of the data between the training set from Memorial Sloan-Kettering Cancer Center and the Scandinavian external validation set is important to help ensure the models are applicable to patients in various settings with differing demographics and treatment philosophies. We considered disease-specific, laboratory, and demographic information, and the surgeon's estimate of survival. For each model, we calculated the area under the ROC curve (AUC) as a metric of discriminatory ability and the Net Benefit using DCA to determine whether the models were suitable for clinical use. RESULTS: On external validation, the AUC for the 1- and 6-month models were 0.76 (95% CI, 0.72-0.80) and 0.76 (95% CI, 0.73-0.79), respectively. The models conferred a positive net benefit on DCA, indicating each could be used rather than assume all patients or no patients would survive greater than 1 or 6 months, respectively. CONCLUSIONS: Decision analysis confirms that the 1- and 6-month Bayesian models are suitable for clinical use. CLINICAL RELEVANCE: These data support upgrading www.pathfx.org with the algorithms described above, which is designed to guide surgical decision-making, and function as a risk stratification method in support of clinical trials. This updating has been done, so now surgeons may use any web browser to generate survival estimates at 1, 3, 6, and 12 months after surgery, at no cost. Just as short estimates of survival help justify palliative therapy or less-invasive approaches to stabilization, more favorable survival estimates at 6 or 12 months are used to justify more durable, complicated, and expensive reconstructive options.

How Does the Level of Nerve Root Resection in En Bloc Sacrectomy Influence Patient-Reported Outcomes?

BACKGROUND: For patients with sacral tumors, who are well enough for surgery, en bloc resection is the preferred treatment. Survival, postoperative complications, and recurrent rates have been described, but patient-reported outcomes often are not included in these studies. QUESTIONS/PURPOSES: The purposes of this study were (1) to compare patient-reported outcomes after en bloc sacrectomy, based on the level of sacral nerve root resection, in terms of mental health, physical health, bowel function, and sexual function; and (2) to assess differences in terms of mental health, physical health, and pain between patients with and without a colostomy. METHODS: A total of 74 patients, of whom 58 (78%) were diagnosed with chordoma, were surveyed between February 2012 and October 2014. This represented 48% of patients with sacral chordoma who were alive and who had been treated with a transverse sacral resection between June 2000 and August 2013 at three institutions with a minimum followup of 6 months (mean, 59 months; range, 6-255 months). We chose 6 months because we believe that neurologic deficits generally are stable by this point and that patients generally have recovered from the operation by this time. Patients were divided into five groups based on the most caudal nerve root spared: L5 (N = 10), S1 (N = 22), S2 (N = 17), S3 (N = 18), and S4 (N = 7). Only postoperative outcomes were collected using the National institute of Health's Patient Reported Measurement Information System (PROMIS) Global Health survey, PROMIS Pain Interference survey, PROMIS Pain Intensity survey, PROMIS Sexual Function survey, and the Modified Obstruction and Defecation Score survey. RESULTS: Differences between two adjacent levels were found in terms of mental health, physical health, and sexual function. Patients in whom the S2 nerve roots were spared had a lower mental health score (median = 44, interquartile range [IQR] = 41-51) than patients in whom the S3 nerve roots were spared (median = 53, IQR = 48-56, q = 0.049). Patients in whom the S2 nerve roots were spared had a slightly lower physical health score (median = 42, IQR = 40-51) than patients in whom the S3 nerve roots were spared (median = 47, IQR = 45-54, q = 0.043). Patients in whom the S1 roots were spared (median = 1.0, range = 1.0-1.0) had a lower orgasm score than patients in whom the S2 nerve roots were spared (median = 3, range = 2-5, q = 0.027). No differences in terms of mental health, physical health, or pain were found between the colostomy group and the no colostomy group. CONCLUSIONS: The combination of our findings can be used to further educate patients and discuss expectations. In an operative setting, these data can be considered when deciding to place a colostomy. LEVEL OF EVIDENCE: Level III, therapeutic study.

Genomic aberrations frequently alter chromatin regulatory genes in chordoma.

Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ∼8 Mb segment at 3p21.1-p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (∼23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (∼40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. © 2016 Wiley Periodicals, Inc.

Factitious disorder (Munchausen's syndrome) in oncology: case report and literature review.

BACKGROUND: Factitious disorder is where patients repeatedly seek medical care for feigned illnesses in the absence of obvious external rewards; 'Munchausen's syndrome' is the historical name for this disorder. METHOD: We report on a case that was presented to a tertiary oncology center as a suspected rare bone cancer. RESULTS AND CONCLUSIONS: Psychosocial clinicians working in oncology settings should be aware of the complexities of diagnosing factitious disorder in cancer settings where empathy is prominent and suspicion unusual. Moreover, comorbidity can cloud the diagnosis (in this case substance abuse), and, even when accurately diagnosed, there are no evidence-based management approaches to offer to the patient. What seems to linger most after the patient is discharged, usually in a huff, are strong counter-transference feelings and substantial medical bills. Copyright © 2015 John Wiley & Sons, Ltd.

Revision Distal Femoral Arthroplasty With the Compress(®) Prosthesis Has a Low Rate of Mechanical Failure at 10 Years.

BACKGROUND: Patients with failed distal femoral megaprostheses often have bone loss that limits reconstructive options and contributes to the high failure rate of revision surgery. The Compress(®) Compliant Pre-stress (CPS) implant can reconstruct the femur even when there is little remaining bone. It differs from traditional stemmed prostheses because it requires only 4 to 8 cm of residual bone for fixation. Given the poor long-term results of stemmed revision constructs, we sought to determine the failure rate and functional outcomes of the CPS implant in revision surgery. QUESTIONS/PURPOSES: (1) What is the cumulative incidence of mechanical and other types of implant failure when used to revise failed distal femoral arthroplasties placed after oncologic resection? (2) What complications are characteristic of this prosthesis? (3) What function do patients achieve after receiving this prosthesis? METHODS: We retrospectively reviewed 27 patients who experienced failure of a distal femoral prosthesis and were revised to a CPS implant from April 2000 to February 2013. Indications for use included a minimum 2.5 mm cortical thickness of the remaining proximal femur, no prior radiation, life expectancy > 10 years, and compliance with protected weightbearing for 3 months. The cumulative incidence of failure was calculated for both mechanical (loss of compression between the implant anchor plug and spindle) and other failure modes using a competing risk analysis. Failure was defined as removal of the CPS implant. Followup was a minimum of 2 years or until implant removal. Median followup for patients with successful revision arthroplasty was 90 months (range, 24-181 months). Functional outcomes were measured with the Musculoskeletal Tumor Society (MSTS) functional assessment score. RESULTS: The cumulative incidence of mechanical failure was 11% (95% confidence interval [CI], 4%-33%) at both 5 and 10 years. These failures occurred early at a median of 5 months. The cumulative incidence of other failures was 18% (95% CI, 7%-45%) at 5 and 10 years, all of which were deep infection. Three patients required secondary operations for cortical insufficiency proximal to the anchor plug in bone not spanned by the CPS implant and unrelated to the prosthesis. Median MSTS score was 27 (range, 24-30). CONCLUSIONS: Revision distal femoral replacement arthroplasty after a failed megaprosthesis is often difficult as a result of a lack of adequate bone. Reconstruction with the CPS implant has an 11% failure rate at 10 years. Our results are promising and demonstrate the durable fixation provided by the CPS implant. Further studies to compare the CPS prosthesis and other reconstruction options with respect to survival and functional outcomes are warranted. LEVEL OF EVIDENCE: Level IV, therapeutic study.

How Does the Level of Sacral Resection for Primary Malignant Bone Tumors Affect Physical and Mental Health, Pain, Mobility, Incontinence, and Sexual Function?

BACKGROUND: En bloc resection for treatment of sacral tumors is the approach of choice for patients with resectable tumors who are well enough to undergo surgery, and studies describe patient survival, postoperative complications, and recurrence rates associated with this treatment. However, most of these studies do not provide patient-reported functional outcomes other than binary metrics for bowel and bladder function postresection. QUESTIONS/PURPOSES: The purpose of this study was to use validated patient-reported outcomes tools to compare quality of life based on level of sacral resection in terms of (1) physical and mental health; (2) pain; (3) mobility; and (4) incontinence and sexual function. METHODS: Our analysis included 33 patients (19 men, 14 women) who had a mean age of 53 years (range, 22-72 years) with a quality-of-life survey administered at a mean postoperative followup of 41 months (range, 6-123 months). The majority of patient-reported quality-of-life outcome surveys for this study were taken from the National Institute of Health's Patient Reported Outcome Measurement Information System (PROMIS) system. To assess physical and mental health, the PROMIS Global Items Survey with physical and mental subscores, Anxiety, and Depression scores were used. Pain outcomes were assessed using PROMIS Pain Intensity and Pain Interference surveys. Patient-reported lower extremity function was assessed using the PROMIS Mobility Survey. Patient-reported quality of life for sexual function was assessed using the PROMIS Sex Interest and Orgasm survey, whereas incontinence was measured using the International Continence Society Voiding and Incontinence scores and the Modified Obstruction and Defecation Score. Surveys were collected prospectively during clinic visits in the postoperative period. Patients were grouped by the level of osteotomy as determined by review of postoperative MRI or CT and half levels were grouped with the more cephalad level. This resulted in the inclusion of total sacrectomy (N = 6), S1 (N = 8), S2 (N = 10), S3 (N = 5), and S4 (N = 4). One-way analysis of variance tests on means or ranks were used to conduct statistical analysis between levels. RESULTS: Patients with more caudal resections had higher physical health (95% confidence interval [CI] total sacrectomy 36-42 versus S4 50-64, p < 0.001), less intense pain (95% CI total sacrectomy 47-60 versus S4 28-37, p < 0.001), less interference resulting from pain (95% CI total sacrectomy 58-69 versus S4 36-51, p = 0.004), higher mobility (95% CI total sacrectomy 24-46 versus S4 59-59, p = 0.002), and were more functionally able to achieve orgasm (95% CI S1 1-1 versus S4 2.2-5.3, p = 0.043). No difference was found for PROMIS Global Item Mental Health Subscore, Sex Interest, Sex Satisfaction, modified obstruction and defecation score, and International Continence Society Voiding and Incontinence although this could be the result of an inadequate sample size. CONCLUSIONS: Our analysis on patient-reported quality of life based on the level of bony resection in patients who underwent resection for primary sacral tumor indicates that patients with higher resections have more pain and loss of physical function in comparison to patients with lower resections. Additionally, use of the PROMIS outcomes allows for comparisons to normative data. LEVEL OF EVIDENCE: Level III, therapeutic study.

Severe Hemodynamic Collapse During Humerus Stabilization with Photodynamic Implant: A Report of Two Cases.

CASE: We present 2 cases of severe hemodynamic collapse during prophylactic stabilization of impending pathologic humerus fractures using a photodynamic bone stabilization device. Both events occurred when the monomer was infused under pressure into a balloon catheter. CONCLUSION: We suspect that an increase in intramedullary pressure during balloon expansion may cause adverse systemic effects similar to fat embolism or bone cement implantation syndrome. Appropriate communication with the anesthesia team, invasive hemodynamic monitoring, and prophylactic vent hole creation may help mitigate or manage these adverse systemic effects.

The Role of En Bloc Resection in the Modern Era for Primary Spine Tumors.

STUDY DESIGN: A literature review. OBJECTIVE: The aim of this review is to provide an overview of benign and malignant primary spine tumors and a balanced analysis of the benefits and limitations of (and alternatives to) surgical treatment with en bloc resection. SUMMARY OF BACKGROUND DATA: Primary spine tumors are rare but have the potential to cause severe morbidity, either from the disease itself or as a result of treatment. The prognosis, goals, and treatment options vary significantly with the specific disease entity. Appropriate initial management is critical; inappropriate surgery before definitive treatment can lead to recurrence and may render the patient incurable, as salvage options are often inferior. METHODS: We performed a comprehensive search of the PubMed database for articles relevant to primary spine neoplasms and en bloc spine surgery. Institutional review board approval was not needed. RESULTS: Although Enneking-appropriate en bloc surgery can be highly morbid, it often provides the greatest chance for local control and/or patient survival. However, there is growing data to support modern radiotherapy as a feasible and less morbid approach to certain primary neoplasms that historically were considered radioresistant. CONCLUSIONS: Choosing the optimal approach to primary spine tumors is complex. A comprehensive and up-to-date assessment of the evidence is required to guide patient care and to balance the often-competing goals of prolonging life and preserving quality of life.

Haptic robot-assisted surgery improves accuracy of wide resection of bone tumors: a pilot study.

BACKGROUND: Accurate reproduction of the preoperative plan at the time of surgery is critical for wide resection of primary bone tumors. Robotic technology can potentially help the surgeon reproduce a given preoperative plan, but yielding control of cutting instruments to a robot introduces potentially serious complications. We developed a novel passive ("haptics") robot-assisted resection technique for primary bone sarcomas that takes advantage of robotic accuracy while still leaving control of the cutting instrument in the hands of the surgeon. QUESTIONS/PURPOSES: We asked whether this technique would enable a preoperative resection plan to be reproduced more accurately than a standard manual technique. METHODS: A joint-sparing hemimetaphyseal resection was precisely outlined on the three-dimensionally reconstructed image of a representative Sawbones femur. The indicated resection was performed on 12 Sawbones specimens using the standard manual technique on six specimens and the haptic robotic technique on six specimens. Postresection images were quantitatively analyzed to determine the accuracy of the resections compared to the preoperative plan, which included measuring the maximum linear deviation of the cuts from the preoperative plan and the angular deviation of the resection planes from the target planes. RESULTS: Compared with the manual technique, the robotic technique resulted in a mean improvement of 7.8 mm of maximum linear deviation from the preoperative plan and 7.9° improvement in pitch and 4.6° improvement in roll for the angular deviation from the target planes. CONCLUSIONS: The haptic robot-assisted technique improved the accuracy of simulated wide resections of bone tumors compared with manual techniques. CLINICAL RELEVANCE: Haptic robot-assisted technology has the potential to enhance primary bone tumor resection. Further bench and clinical studies, including comparisons with recently introduced computer navigation technology, are warranted.

Compress knee arthroplasty has 80% 10-year survivorship and novel forms of bone failure.

BACKGROUND: Compliant, self-adjusting compression technology is a novel approach for durable prosthetic fixation of the knee. However, the long-term survival of these constructs is unknown. QUESTIONS/PURPOSES: We therefore determined the survival of the Compress prosthesis (Biomet Inc, Warsaw, IN, USA) at 5 and 10 actuarial years and identified the failure modes for this form of prosthetic fixation. METHODS: We retrospectively reviewed clinical and radiographic records for all 82 patients who underwent Compress knee arthroplasty from 1998 to 2008, as well as one patient who received the device elsewhere but was followed at our institution. Prosthesis survivorship and modes of failure were determined. Followup was for a minimum of 12 months or until implant removal (median, 43 months; range, 6-131 months); 28 patients were followed for more than 5 years. RESULTS: We found a survivorship of 85% at 5 years and 80% at 10 years. Eight patients required prosthetic revision after interface failure due to aseptic loosening alone (n = 3) or aseptic loosening with periprosthetic fracture (n = 5). Additionally, five periprosthetic bone failures occurred that did not require revision: three patients had periprosthetic bone failure without fixation compromise and two exhibited irregular prosthetic osteointegration patterns with concomitant fracture due to mechanical insufficiency. CONCLUSIONS: Compress prosthetic fixation after distal femoral tumor resection exhibits long-term survivorship. Implant failure was associated with patient nonadherence to the recommended weightbearing proscription or with bone necrosis and fracture. We conclude this is the most durable FDA-approved fixation method for distal femoral megaprostheses. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Surgical technique: Computer-generated custom jigs improve accuracy of wide resection of bone tumors.

BACKGROUND: Manual techniques of reproducing a preoperative plan for primary bone tumor resection using rudimentary devices and imprecise localization techniques can result in compromised margins or unnecessary removal of unaffected tissue. We examined whether a novel technique using computer-generated custom jigs more accurately reproduces a preoperative resection plan than a standard manual technique. DESCRIPTION OF TECHNIQUE: Using CT images and advanced imaging, reverse engineering, and computer-assisted design software, custom jigs were designed to precisely conform to a specific location on the surface of partially skeletonized cadaveric femurs. The jigs were used to perform a hemimetaphyseal resection. METHODS: We performed CT scans on six matched pairs of cadaveric femurs. Based on a primary bone sarcoma model, a joint-sparing, hemimetaphyseal wide resection was precisely outlined on each femur. For each pair, the resection was performed using the standard manual technique on one specimen and the custom jig-assisted technique on the other. Superimposition of preoperative and postresection images enabled quantitative analysis of resection accuracy. RESULTS: The mean maximum deviation from the preoperative plan was 9.0 mm for the manual group and 2.0 mm for the custom-jig group. The percentages of times the maximum deviation was greater than 3 mm and greater than 4 mm was 100% and 72% for the manual group and 5.6% and 0.0% for the custom-jig group, respectively. CONCLUSIONS: Our findings suggest that custom-jig technology substantially improves the accuracy of primary bone tumor resection, enabling a surgeon to reproduce a given preoperative plan reliably and consistently.