Earlier Radiation Is Associated with Improved 1-Year Survival After Metastatic Spine Tumor Surgery

OBJECTIVES

In patients undergoing metastatic spine surgery, we sought to: 1) report time to postoperative radiation therapy (RT), 2) describe the predictive factors of time to postoperative RT, and 3) determine if earlier postoperative RT is associated with improved local recurrence (LR) and overall survival (OS).

METHODS

A single-center, retrospective cohort study was undertaken of all patients undergoing spine surgery for extradural metastatic disease and receiving RT within 3-months postoperatively between 02/2010-01/2021. Time to postoperative RT was dichotomized at <1month vs. 1-3months. The primary outcomes were LR, OS, and 1-year survival. Secondary outcomes were wound complication, Karnofsky Performance Scale (KPS), and Modified McCormick Scale (MMS). Regression analyses controlled for age, BMI, tumor size, preoperative RT, preoperative/postoperative chemotherapy, and type of RT.

RESULTS

Of 76 patients undergoing spinal metastasis surgery and receiving postoperative RT within 3-months, 34(44.7%) received RT within 1month and 42(55.2%) within 1-3months. Patients with larger tumor size (β=-3.58,95%CI=-6.59,-0.57,p=0.021) or new neurological deficits (β=-16.21,95%CI=-32.21,-0.210,p=0.047) had a shorter time to RT. No significant association was found between time to RT and LR or OS on multivariable logistic/Cox regression. However, patients who received RT between 1-3month had a lower odd of 1-year survival compared to those receiving RT within 1month (OR=0.18,95%CI=0.04-0.74,p=0.022). Receiving RT within 1month vs. 1-3month was not associated with wound complications (7.1% vs. 2.9%,p=0.556)(OR=4.40,95%CI=0.40-118.0,p=0.266) or KPS/MMS.

CONCLUSIONS

Spine surgeons, oncologists, and radiation oncologists should make every effort to start RT within 1 month to improve 1-year survival after metastatic spine tumor surgery.

Does Preoperative Bilsky Score Predict Outcome Following Surgical Resection of Primary Tumors of the Spine?

OBJECTIVE

In patients undergoing surgery for primary bone tumors of the spine, we sought to compare Bilsky score 0-1 versus 2-3 in: 1) preoperative presentation, 2) perioperative variables, and 3) long-term outcomes.

METHODS

A single-center, retrospective cohort study was undertaken of patients undergoing surgery for extradural, primary bone tumors of the spine between January 2010 and January 2021. The primary exposure variable was Bilsky score, dichotomized as 0-1 versus 2-3. Survival analysis was performed to assess local recurrence (LR) and overall survival (OS).

RESULTS

Of 38 patients undergoing resection of primary spinal tumors, 19 (50.0%) patients presented with Bilsky 0-1 and 19 (50.0%) Bilsky 2-3 grades. The most common diagnosis was chondrosarcoma (33.3%), followed by chordoma (16.7%). There were 15 (62.5%) malignant tumors. Preoperatively, there was no significant difference in demographics, Karnofsky Performance Scale (KPS) (P > 0.999), or motor deficit (P > 0.999). Perioperatively, no difference was found in operative time (P = 0.954), blood loss (P = 0.416), length of stay (P = 0.641), neurologic deficit (P > 0.999), or discharge disposition (P = 0.256). No difference was found in Enneking resection status (69.2% vs. 54.5%, P = 0.675). Long-term, no differences were found regarding reoperation (P = 0.327), neurologic deficit (P > 0.999), postoperative KPS (P = 0.605) and modified McCormick Scale (MMS) (P = 0.870). No difference was observed in KPS (P = 0.418) and MMS (P = 0.870) at last follow-up. However, patients with Bilsky 2-3 had shorter time to LR (1715.0 vs. 513.0 ± 633.4 days, log-rank; P = 0.002) and shorter OS (2025.0 ± 1165.3 vs. 794.0 ± 952.6 days, log-rank; P = 0.002).

CONCLUSIONS

Bilsky 2-3 lesions were associated with shorter time to LR and shorter OS. Patients harboring primary spinal tumors with higher grade Bilsky score appear to be at a higher risk for worse outcomes.

Comparison of Outcomes in Patients with Cervical Spine Metastasis After Different Surgical Approaches: A Single-Center Experience

OBJECTIVE

In patients undergoing cervical spine surgery for metastatic spine disease, we sought to 1) compare perioperative and oncologic outcomes among 3 different operative approaches, 2) report fusion rates, and 3) compare different types of anterior vertebral body replacement.

METHODS

A single-center retrospective cohort study of patients undergoing extradural cervical/cervicothoracic spine metastasis surgery between February 2010 and January 2021 was conducted. Operative approaches were anterior-alone, posterior-alone, or combined anterior-posterior, and the grafts/cages used in the anterior fusions were cortical allografts, static cages, or expandable cages. All cages were filled with autograft/allograft. Outcomes included perioperative/postoperative variables, along with fusion rates, functional status, local recurrence (LR), and overall survival (OS).

RESULTS

Sixty-one patients underwent cervical spine surgery for metastatic disease, including 11 anterior (18.0%), 28 posterior (45.9%), and 22 combined (36.1%). New postoperative neurologic deficit was the highest in the anterior approach group (P = 0.038), and dysphagia was significantly higher in the combined approach group (P = 0.001). LR (P > 0.999), OS (P = 0.655), and time to both outcomes (log-rank test, OS, P = 0.051, LR, P = 0.187) were not significantly different. Of the 51 patients alive at 3 months, only 19 (37.2%) obtained imaging ≥3 months. Fusion was seen in 11/19 (57.8%) at a median of 8.3 months (interquartile range, 4.6-13.7). Among the anterior corpectomies, the following graft/cage was used: 6 allografts (54.5%), 4 static cages (36.3%), and 1 expandable cage (9.0%), with no difference found in outcomes among the 3 groups.

CONCLUSIONS

The only discernible differences between operative approaches were that patients undergoing an anterior approach had higher rates of new postoperative neurologic deficit, and the combined approach group had higher rates of postoperative dysphagia.

Impact of comorbidities on immediate post-operative complications in oral cavity free flap patients

PURPOSE

To examine the relationship between comorbidities and the development of immediate post-operative complications in patients undergoing oral cavity composite resection (OCCR) with free flap (FF) reconstruction.

MATERIALS AND METHODS

Retrospective analysis was completed on all consecutive OCCRs with FF reconstruction performed at a single quaternary care facility between 1999 and 2020. Comorbidities, immediate post-operative complications, patient demographics, and tumor characteristics were collected. Odds ratios (OR) with 95 % confidence intervals were calculated for associations between comorbidities and immediate post-operative complications.

RESULTS

320 patients who underwent OCCR with FF reconstruction were included. One hundred twenty-one (37.8 %) patients developed a post-operative complication during their initial hospital admission. The most common complications were non-pneumonia cardiopulmonary events (14.1 %), pneumonia (9.4 %), and wound infection (8.4 %). Other complications included flap compromise, bleeding, and fistula. On multivariate analysis, patients without comorbid conditions were less likely to develop a post-operative complication (OR 0.64; 0.41-0.98). Atrial fibrillation (OR 2.94; 1.17-7.39) and cerebrovascular disease (OR 2.28; 1.08-4.84) were associated with increased odds of developing any complications. Furthermore, cerebrovascular disease (OR: 2.33; 1.04-5.39) and peripheral vascular disease (OR: 2.7; 1.2-6.08) were independently associated with pneumonia.

CONCLUSION

In this retrospective review of patients undergoing OCCR with FF reconstruction for oral cavity SCC, lack of identifiable comorbidities appeared to be protective for post-operative complications while atrial fibrillation and cerebrovascular disease were associated with increased odds of any complication. Pre-existing vascular disease was also associated with an increased risk of pneumonia.

Does Low-Grade Versus High-Grade Bilsky Score Influence Local Recurrence and Overall Survival in Metastatic Spine Tumor Surgery?

BACKGROUND AND OBJECTIVES

Spinal cord compression caused by spinal tumors is measured using the epidural spinal cord compression scale, also known as the Bilsky score. Whether Bilsky score predicts short-/long-term outcomes remains unknown. The objectives were to determine the correlation of Bilsky score 0-1 vs 2-3 with regards to (1) preoperative presentation, (2) perioperative variables, and (3) long-term outcomes.

METHODS

A single-center, retrospective evaluation of a cohort of patients undergoing metastatic spine surgery was performed between 01/2010 and 01/2021. Multivariable logistic/linear/Cox regression were performed controlling for age, body mass index, race, total decompressed levels, tumor size, other organ metastases, and postoperative radiotherapy/chemotherapy.

RESULTS

Of 343 patients with extradural spinal metastasis, 92 (26.8%) were Bilsky 0-1 and 251 (73.2%) were Bilsky 2-3. Preoperatively, patients with Bilsky 2-3 lesions were older ( P = .008), presented more with sensory deficits ( P = .029), and had worse preoperative Karnofsky Performance Scale (KPS) ( P = .002). Perioperatively, Bilsky 2-3 patients had more decompressed levels ( P = .005) and transpedicular decompression ( P < .001), with similar operative time ( P = .071) and blood loss ( P = .502). Although not statistically significant, patients with Bilsky 2-3 had more intraoperative neuromonitoring changes ( P = .412). Although rates of complications ( P = .442) and neurological deficit ( P = .852) were similar between groups, patients with Bilsky 2-3 lesions had a longer length of stay ( P = .007) and were discharged home less frequently ( P < .001). No difference was found in 90-day readmissions ( P = .607) and reoperation ( P = .510) Long-term: LR ( P =.100) and time to LR (log-rank; P =0.532) were not significantly different between Bilsky 0-1 and Bilsky 2-3 lesions. However, patients with Bilsky 2-3 lesions had worse postoperative KPS ( P < .001), worse modified McCormick scale score ( P = .003), shorter overall survival (OS) (log-rank; P < .001), and worse survival at 1 year ( P = .012). Bilsky 2-3 lesions were associated with shorter OS on multivariable Cox regression (hazard ratio = 1.78, 95% CI = 1.27-2.49, P < .001), with no significant impact on time to LR (hazard ratio = 0.73, 95% CI = 0.37-1.44, P = .359).

CONCLUSION

Bilsky 2-3 lesions were associated with longer length of stay, more nonhome discharge, worse postoperative KPS/modified McCormick scale score, shorter OS, and reduced survival at 1 year. Higher-grade Bilsky score lesions appear to be at a higher risk for worse outcomes. Efforts should be made to identify metastatic spine patients before they reach the point of severe spinal cord compression..

Neurological Examination Frequency and Time-to-Delirium After Traumatic Brain Injury

BACKGROUND

Frequent neurological examinations in patients with traumatic brain injury (TBI) disrupt sleep-wake cycles and potentially contribute to the development of delirium.

OBJECTIVE

To evaluate the risk of delirium among patients with TBI with respect to their neuro-check frequencies.

METHODS

A retrospective study of patients presenting with TBI at a single level I trauma center between January 2018 and December 2019. The primary exposure was the frequency of neurological examinations (neuro-checks) assigned at the time of admission. Patients admitted with hourly (Q1) neuro-check frequencies were compared with those who received examinations every 2 (Q2) or 4 (Q4) hours. The primary outcomes were delirium and time-to-delirium. The onset of delirium was defined as the first documented positive Confusion Assessment Method for the Intensive Care Unit score.

RESULTS

Of 1552 patients with TBI, 458 (29.5%) patients experienced delirium during their hospital stay. The median time-to-delirium was 1.8 days (IQR: 1.1, 2.9). Kaplan-Meier analysis demonstrated that patients assigned Q1 neuro-checks had the greatest rate of delirium compared with the patients with Q2 and Q4 neuro-checks ( P < .001). Multivariable Cox regression modeling demonstrated that Q2 neuro-checks (hazard ratio: 0.439, 95% CI: 0.33-0.58) and Q4 neuro-checks (hazard ratio: 0.48, 95% CI: 0.34-0.68) were protective against the development of delirium compared with Q1. Other risk factors for developing delirium included pre-existing dementia, tobacco use, lower Glasgow Coma Scale score, higher injury severity score, and certain hemorrhage patterns.

CONCLUSION

Patients with more frequent neuro-checks had a higher risk of developing delirium compared with those with less frequent neuro-checks.

Longer Screws Decrease the Risk of Radiographic Pseudarthrosis Following Elective Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

In patients undergoing elective anterior cervical discectomy and fusion (ACDF), we sought to determine the impact of screw length on: (1) radiographic pseudarthrosis, (2) pseudarthrosis requiring reoperation, and (3) patient-reported outcome measures (PROMs).

METHODS

A single-institution, retrospective cohort study was undertaken from 2010-21. The primary independent variables were: screw length (mm), screw length divided by the anterior-posterior vertebral body diameter (VB%), and the presence of any screw with VB% < 75% vs all screws with VB% ≥ 75%. Multivariable logistic regression controlled for age, BMI, gender, smoking, American Society of Anesthesiology grade, number of levels fused, and whether a corpectomy was performed.

RESULTS

Of 406 patients undergoing ACDF, levels fused were: 1-level (39.4%), 2-level (42.9%), 3-level (16.7%), and 4-level (1.0%). Mean screw length was 14.3 ± 2.3 mm, and mean VB% was 74.4 ± 11.2. A total of 293 (72.1%) had at least one screw with VB% < 75%, 113 (27.8%) had all screws with VB% ≥ 75%, and 141 (34.7%) patients had radiographic pseudarthrosis at 1-year. Patients who had any screw with VB% < 75% had a higher rate of radiographic pseudarthrosis compared to those had all screws with VB% ≥ 75% (39.6% vs 22.1%, P < .001). Multivariable logistic regression revealed that a higher VB% (OR = .97, 95%CI = .95-.99, P = .035) and having all screws with VB% ≥ 75% (OR = .51, 95%CI = .27-.95, P = .037) significantly decreased the odds of pseudarthrosis at 1-year, with no difference in reoperation or PROMs (all P > .05).

CONCLUSION

Longer screws taking up ≥75% of the vertebral body protected against radiographic pseudarthrosis at 1-year. Maximizing screw length in ACDF is an easily modifiable factor directly under the surgeon's control that may mitigate the risk of pseudarthrosis.

Palliative Care Consultation Utilization Among Patient Undergoing Surgery for Metastatic Spinal Tumors

OBJECTIVE

In patients undergoing surgery for spinal metastasis, we sought to: (1) describe patterns of palliative care consultation, (2) evaluate the factors that trigger palliative care consultation, and (3) determine the association of palliative care consultation on longer-term outcomes.

METHODS

A single-center, retrospective, case-control study was conducted for patients undergoing spinal metastasis surgery from February 2010 to January 2021. The primary outcome was receiving a palliative care consultation, and the timing of consultation was divided into same hospital stay consultation, preoperative versus postoperative consultation, and early (

RESULTS

Of 363 patients undergoing surgery for spinal metastasis, 62 (17.0%) patients received palliative care consultation during the same hospitalization, 11 (17.7%) were preoperative, and 51 (82.2%) were postoperative. Among same-stay consultations, 32 (51.6%) were early and 30 (48.4%) were late. Palliative care consultation recipients had worse preoperative Karnofsky Performance Scale (KPS) score (P < 0.001), were more likely to have other organ metastases (P = 0.005) or cord compression (P = 0.026), had longer hospitalization (P < 0.001), and were less likely to be discharged home (P < 0.001). Patients presenting with mechanical pain were more likely to receive preoperative consults compared with postoperative (P = 0.029), and earlier compared with later consultations (P = 0.046). Regarding long-term outcomes, patients with same-stay palliative care consultation had significantly shorter overall survival (log-rank; P < 0.001), worse KPS postoperatively (P = 0.017), and worse KPS and Modified McCormick Scale at the last follow-up (P < 0.001).

CONCLUSIONS

Only 1 in 6 patients received palliative care consultation. Patients receiving same-stay palliative care consultation had more advanced local and systemic disease burden. Increased utilization of palliative care consultation in patients with spine metastasis is needed.

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Key Words

• Overall survival
• Palliative care
• Spinal metastasis
• Spinal tumors

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MESH Headings

• Humans
• Palliative Care
• Spinal Neoplasms/secondary
• Retrospective Studies
• Case-Control Studies
• Spinal Cord Neoplasms
• Central Nervous System Neoplasms
• Referral and Consultation

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Affiliation(s)

Jeffrey W Chen Vanderbilt University, School of Medicine, Nashville, Tennessee, USA
Hani Chanbour Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
Gabriel A Bendfeldt Vanderbilt University, School of Medicine, Nashville, Tennessee, USA
Lakshmi Suryateja Gangavarapu Vanderbilt University, School of Medicine, Nashville, Tennessee, USA
Mohana B Karlekar Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
Amir M Abtahi Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Orthopedic Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
Byron F Stephens Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Orthopedic Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
Scott L Zuckerman Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Orthopedic Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
Silky Chotai Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA.

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Is the Number of National Database Research Studies in Musculoskeletal Sarcoma Increasing, and Are These Studies Reliable?

BACKGROUND

Large national databases have become a common source of information on patterns of cancer care in the United States, particularly for low-incidence diseases such as sarcoma. Although aggregating information from many hospitals can achieve statistical power, this may come at a cost when complex variables must be abstracted from the medical record. There is a current lack of understanding of the frequency of use of the Surveillance, Epidemiology, and End Results (SEER) database and the National Cancer Database (NCDB) over the last two decades in musculoskeletal sarcoma research and whether their use tends to produce papers with conflicting findings.

QUESTIONS/PURPOSES

(1) Is the number of published studies using the SEER and NCDB databases in musculoskeletal sarcoma research increasing over time? (2) What are the author, journal, and content characteristics of these studies? (3) Do studies using the SEER and the NCDB databases for similar diagnoses and study questions report concordant or discordant key findings? (4) Are the administrative data reported by our institution to the SEER and the NCDB databases concordant with the data in our longitudinally maintained, physician-run orthopaedic oncology dataset?

METHODS

To answer our first three questions, PubMed was searched from 2001 through 2020 for all studies using the SEER or the NCDB databases to evaluate sarcoma. Studies were excluded from the review if they did not use these databases or studied anatomic locations other than the extremities, nonretroperitoneal pelvis, trunk, chest wall, or spine. To answer our first question, the number of SEER and NCDB studies were counted by year. The publication rate over the 20-year span was assessed with simple linear regression modeling. The difference in the mean number of studies between 5-year intervals (2001-2005, 2006-2010, 2011-2015, 2016-2020) was also assessed with Student t-tests. To answer our second question, we recorded and summarized descriptive data regarding author, journal, and content for these studies. To answer our third question, we grouped all studies by diagnosis, and then identified studies that shared the same diagnosis and a similar major study question with at least one other study. We then categorized study questions (and their associated studies) as having concordant findings, discordant findings, or mixed findings. Proportions of studies with concordant, discordant, or mixed findings were compared. To answer our fourth question, a coding audit was performed assessing the concordance of nationally reported administrative data from our institution with data from our longitudinally maintained, physician-run orthopaedic oncology dataset in a series of patients during the past 3 years. Our orthopaedic oncology dataset is maintained on a weekly basis by the senior author who manually records data directly from the medical record and sarcoma tumor board consensus notes; this dataset served as the gold standard for data comparison. We compared date of birth, surgery date, margin status, tumor size, clinical stage, and adjuvant treatment.

RESULTS

The number of musculoskeletal sarcoma studies using the SEER and the NCDB databases has steadily increased over time in a linear regression model (β = 2.51; p < 0.001). The mean number of studies per year more than tripled during 2016-2020 compared with 2011-2015 (39 versus 13 studies; mean difference 26 ± 11; p = 0.03). Of the 299 studies in total, 56% (168 of 299) have been published since 2018. Nineteen institutions published more than five studies, and the most studies from one institution was 13. Orthopaedic surgeons authored 35% (104 of 299) of studies, and medical oncology journals published 44% (130 of 299). Of the 94 studies (31% of total [94 of 299]) that shared a major study question with at least one other study, 35% (33 of 94) reported discordant key findings, 29% (27 of 94) reported mixed key findings, and 44% (41 of 94) reported concordant key findings. Both concordant and discordant groups included papers on prognostic factors, demographic factors, and treatment strategies. When we compared nationally reported administrative data from our institution with our orthopaedic oncology dataset, we found clinically important discrepancies in adjuvant treatment (19% [15 of 77]), tumor size (21% [16 of 77]), surgery date (23% [18 of 77]), surgical margins (38% [29 of 77]), and clinical stage (77% [59 of 77]).

CONCLUSION

Appropriate use of databases in musculoskeletal cancer research is essential to promote clear interpretation of findings, as almost two-thirds of studies we evaluated that asked similar study questions produced discordant or mixed key findings. Readers should be mindful of the differences in what each database seeks to convey because asking the same questions of different databases may result in different answers depending on what information each database captures. Likewise, differences in how studies determine which patients to include or exclude, how they handle missing data, and what they choose to emphasize may result in different messages getting drawn from large-database studies. Still, given the rarity and heterogeneity of sarcomas, these databases remain particularly useful in musculoskeletal cancer research for nationwide incidence estimations, risk factor/prognostic factor assessment, patient demographic and hospital-level variable assessment, patterns of care over time, and hypothesis generation for future prospective studies.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Unplanned Readmission After Surgery for Cervical Spine Metastases

OBJECTIVE

Patients undergoing surgery for cervical spine metastases are at risk for unplanned readmission due to comorbidities and chemotherapy/radiation. Our objectives were to: 1) report the incidence of unplanned readmission, 2) identify risk factors associated with unplanned readmission, and 3) determine the impact of an unplanned readmission on long-term outcomes.

METHODS

A single-center, retrospective, case-control study was undertaken of patients undergoing cervical spine surgery for metastatic disease between 02/2010 and 01/2021. The primary outcome of interest was unplanned readmission within 6 months. Survival analysis was performed for overall survival (OS) and local recurrence (LR).

RESULTS

A total of 61 patients underwent cervical spine surgery for metastatic disease with the following approaches: 11 (18.0%) anterior, 28 (45.9%) posterior, and 22 (36.1%) combined. Mean age was 60.9 ± 11.2 years and 38 (62.3%) were males. A total of 9/61 (14.8%) patients had an unplanned readmission, 3 for surgical reasons and 6 for medical reasons. No difference was found in demographics, preoperative Karnofsky Performance Scale (P = 0.992), motor strength (P = 0.477), or comorbidities (P = 0.213) between readmitted patients versus not. Readmitted patients had a higher rate of preoperative radiation (P = 0.009). No statistical differences were found in operative time (P = 0.893), estimated blood loss (P = 0.676), length of stay (P = 0.720), discharge disposition (P = 0.279), and operative approach (P = 0.450). Furthermore, no difference was found regarding complications (P = 0.463), postoperative Karnofsky Performance Scale (P = 0.535), and postoperative Modified McCormick Scale (P = 0.586). Lastly, unplanned readmissions were not associated with OS (log-rank; P = 0.094) or LR (log-rank; P = 0.110).

CONCLUSIONS

In patients undergoing cervical spine metastasis surgery, readmission occurred in 15% of patients, 33% for surgical reasons, and 67% for medical reasons. Preoperative radiotherapy was associated with an increased rate of unplanned readmissions, yet readmission had no association with OS or LR.

Heterozygous mutation of sonic hedgehog receptor (Ptch1) drives cerebellar overgrowth and sex-specifically alters hippocampal and cortical layer structure, activity, and social behavior in female mice

Sonic hedgehog (SHH) signaling is essential for the differentiation and migration of early stem cell populations during cerebellar development. Dysregulation of SHH-signaling can result in cerebellar overgrowth and the formation of the brain tumor medulloblastoma. Treatment for medulloblastoma is extremely aggressive and patients suffer life-long side effects including behavioral deficits. Considering that other behavioral disorders including autism spectrum disorders, holoprosencephaly, and basal cell nevus syndrome are known to present with cerebellar abnormalities, it is proposed that some behavioral abnormalities could be inherent to the medulloblastoma sequalae rather than treatment. Using a haploinsufficient SHH receptor knockout mouse model (Ptch1^+/-), a partner preference task was used to explore activity, social behavior and neuroanatomical changes resulting from dysregulated SHH signaling. Compared to wild-type, Ptch1^+/- females displayed increased activity by traveling a greater distance in both open-field and partner preference tasks. Social behavior was also sex-specifically modified in Ptch1^+/- females that interacted more with both novel and familiar animals in the partner preference task compared to same-sex wild-type controls. Haploinsufficiency of PTCH1 resulted in cerebellar overgrowth in lobules IV/V and IX of both sexes, and female-specific decreases in hippocampal size and isocortical layer thickness. Taken together, neuroanatomical changes related to deficient SHH signaling may alter social behavior.