Allograft reconstruction of the extensor mechanism after resection of soft tissue sarcoma

ISRCTN ISRCTN63060594
DOI https://doi.org/10.1186/ISRCTN63060594
Secondary identifying numbers W-676
Submission date
27/11/2017
Registration date
04/12/2017
Last edited
29/06/2018
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Musculoskeletal Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English Summary

Background and study aims
Soft tissue sarcomas are a group of rare cancers that impact the tissues, connect and support the body and organs. As they are rare and can vary in types, they are hard to diagnose. The knee joint and surrounding area are quite uncommon locations for soft tissue sarcoma. Over the recent decades, limb-sparing surgery has become an accepted method of treatment for most patients with soft tissue sarcomas. Advances in surgical techniques, prosthetic design and bone allograft banking have opened the avenue for reconstruction procedures after wide excision of bone and soft tissues. This allows the surgeon to achieve adequate margins while salvaging the limb and its function. Yet, soft tissue tumors around the knee joint still pose problems for the excision and subsequent reconstruction. Extension of the tumor in the joint or in the extensor mechanism is a challenging situation to achieve adequate margins and a good functional limb. There is no current consensus as to the best method of reconstruction of the extensor mechanism of the knee. Few reconstructive options are available to avoid knee arthrodesis including tendon transfers or local grafts, synthetic materials and allograft tissues. Regardless of the used reconstruction technique, the principal technical difficulty remains restoration of the extensor function and the provision of soft tissue coverage. In the current literature, no data is available considering specifically the demanding situation of soft tissue sarcomas involving the extensor mechanism of the knee. This study aims to highlight the surgical difficulties as well as the oncological and functional results after a resection of the extensor apparatus due to a soft tissue sarcoma.

Who can participate?
Adults aged 34 to 68 years old who underwent surgical resection of their soft tissue sarcoma using the extensor method.

What does the study involve?
Participants who underwent a resection of a soft tissue sarcoma involving the extensor mechanism are contacted and asked to participate in further follow up. Participants are provided with questionnaires to fill out about their knee function. Participants are also follow up with serial clinical and radiographic (x-rays and imaging) of their knee monthly for the first three months of follow up and then periodically for ten years after surgery. This is done to assess the function and if there are any surgical complications of the knee.

What are the possible benefits and risks of participating?
There are no direct benefits or risks for patients taking part in the study. The treatment and surgical indication was identical between patients participating in the study and patients not participating in the study.

Where is the study run from?
1. University Hospital Careggi (Italy)
2. Balgrist University Hospital (Switzerland)

When is the study starting and how long is it expected to run for?
July 2014 to December 2016

Who is funding the study?
Balgrist University Hospital (Swtizerland)

Who is the main contact?
Dr Daniel Müller (Scientific)
daniel.mueller@balgrist.ch

Contact information

Dr Daniel Müller
Scientific

Balgrist University Hospital
Forchstrasse 340
Zürich
8008
Switzerland

Study information

Study designObservational case series
Primary study designObservational
Secondary study designCase series
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details to request a patient information sheet
Scientific titleAllograft reconstruction of the extensor mechanism after resection of soft tissue sarcoma: a case series
Study hypothesisSoft tissue tumors around the knee joint still pose problems for the excision and subsequent reconstruction. The replacement of the extensor mechanism by an allograft is a reasonable option, allowing wide margins and restoration of active extension in most patients.
Ethics approval(s)Local Ethics Commitee Zurich Switzerland, 10/24/2017, ref: 2017-01666
ConditionSoft tissue tumors around the knee joint
InterventionThe database is retrospectively searched for patients who underwent a resection of a soft tissue sarcoma involving the extensor mechanism. From these patients informed consent is obtained. In addition to participants regular follow ups, participants are provided with questionnaires to fill out regarding their knee function. The minimal duration of observation was 2 years. The mean follow-up was 6 years. The frequency of the controls did not vary compared to patients not included in the study.

Participants are followed with serial clinical and radiographic examinations of the limb, combined with CT imaging of the chest. For the first 3 months, clinical and radiographic follow-ups were obtained monthly. Afterwards the intervals were extended to 3 months in the first two years, four months in the 3rd year, 6 months in the 4th, 5th and 6th years and finally once a year until the 10th year after the surgery.
Intervention typeProcedure/Surgery
Primary outcome measure1. Knee function the active range of motion, active flexion and extension lag is measured using the International Society of Limb Salvage (ISOLS) score at yearly follow ups and using data from reviewing the patient charts.
2. Local recurrence rate is measured using Kaplan Meier curve for local recurrence free survival for 10 years. The presence of a local recurrence was detected by careful clinical examination and radiologic controls.
3. Surgical complication rate is measured by registering all the revision surgeries of the included patients during the observational time.
Secondary outcome measures1. Metastatic disease survival is measured using Kaplan Meier curve for metastasis free survival for 10 years. The presence of a metastasis was detected by careful clinical examination and CT chest.
2. Overall disease specific survival is measured using Kaplan Meier curve for overall survival for 10 years.
3. Functional outcome is measured by measuring the active range of motion (°), active flexion and extension lag at the last follow up. The International Society of Limb Salvage (ISOLS) score was calculated at the last follow up.
Overall study start date01/07/2014
Overall study end date31/12/2016

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participants6
Participant inclusion criteria1. Patients who have undergone a surgical resection of a soft tissue sarcoma affecting the quadriceps tendon, the patella and / or the patellar tendon without apparent joint involvement
2. Patients ranged from 34 to 68 years
Participant exclusion criteriaPatients with involvement of the joint space needed an extra-articular knee resection and an allograft prosthetic composite reconstruction.
Recruitment start date01/01/2015
Recruitment end date31/12/2015

Locations

Countries of recruitment

  • Italy
  • Switzerland

Study participating centres

University Hospital Careggi
Firenze
50134
Italy
Balgrist University Hospital
Zürich
8008
Switzerland

Sponsor information

Balgrist University Hospital
Hospital/treatment centre

Forchstrasse 340
Zürich
8008
Switzerland

Website www.balgrist.ch
ROR logo "ROR" https://ror.org/02yzaka98

Funders

Funder type

Hospital/treatment centre

Balgrist University Hospital

No information available

Results and Publications

Intention to publish date04/06/2018
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planThe analysis of the data is finished and a manuscript is ready for submitting in a high-impact peer reviewd journal. We intent to publish the study in the next 6 months. Please use the contact details below to request a study protocol.
IPD sharing planThe datasets generated during and/or analysed during the current study are/will be available upon request from Daniel Müller, daniel.mueller@balgrist.ch.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 22/05/2018 Yes No

Editorial Notes

29/06/2018: Publication reference added.