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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
Mohs micrographic surgery (MMS) in Hong Kong for the treatment of periocular basal cell carcinoma (BCC) through a multidisciplinary approach
Scientific title
Mohs micrographic surgery (MMS) in Hong Kong for the treatment of periocular basal cell carcinoma (BCC) through a multidisciplinary approach
Secondary ID [1] 292921 0
CUHK Project code: 2041356
Secondary ID [2] 292922 0
Joint CUHK-NTEC CREC Research Approval: CRE-2007.467
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
periocular basal cell carcinoma (BCC) 304801 0
Condition category
Condition code
Cancer 304098 304098 0 0
Malignant melanoma

Study type
Description of intervention(s) / exposure
Patients received Mohs Micrographic Surgery(MMS) under a streamlined standard operating procedure emphasizing surgeon-driven mapping, specimen-orientation and clinico-histological correlation with the dermatopathologist at the frozen-section laboratory.

The tumor will be removed in the operating theatre after you have received adequate local anesthesia. It will be carefully marked and sent to the pathology laboratory. The pathologist is going to make very thin cut of the mass and examine the margin carefully. Any remaining tumor will be excised and this procedure will be repeated until all tumor parts are removed. The wound will then be closed on the same day or the next.
Intervention code [1] 299153 0
Treatment: Surgery
Comparator / control treatment
No control group
Control group

Primary outcome [1] 303427 0
Histological growth pattern / subtypes (nodular, superficial, infiltrative, morphea, micronodular, and mixed patterns). Above outcomes are qualitatively evaluated by the investigator after clerking the patient. Medical imaging may be used when necessary.
Timepoint [1] 303427 0
Before the surgery and 1, 4, 12, 26 and 52 weeks after surgery.
Primary outcome [2] 303753 0
Number of Mohs layer used to obtain histological clearance. The number of Mohs layer used will be recorded by counting.
Timepoint [2] 303753 0
During surgery.
Primary outcome [3] 303754 0
Biopsy-confirmed recurrence. Biopsy test will be needed to confirm the diagnosis.
Timepoint [3] 303754 0
After surgery and only if the signs and symptoms of eye suggests the recurrence of cancer.
Secondary outcome [1] 338891 0
Complications at the surgery sites including infection, eyelid malposition, incomplete eyelid closure, dry eye, scarring etc to be qualitatively evaluated by investigators during follow-up of patients.
Timepoint [1] 338891 0
1, 4, 12, 26 and 52 weeks after surgery

Key inclusion criteria
1. Biopsy proven or clinically suspicious BCC
2. Lesion located from zone I to IV with or without extension to zone V of the eye skin
3. Informed consent
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. Non-BCC skin cancer
2. Previously treated (residual, recurrent) BCC
3. Refusal for surgery or follow-up

Study design
Purpose of the study
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Sequence generation is not used.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
Tumors will be grouped by their locations, sizes, histological subtypes. Associations between categorical variables were analyzed using chi-square tests, with the Mantel–Haenszel test for linear association where appropriate. Fisher exact test was used if expected values were less than 5. Comparison of normally distributed variables among groups was performed using t-tests and analysis of variance; their nonparametric equivalent was used for non–normally distributed data. Exact 95% confidence intervals (CIs) were calculated for the recurrence rate. Comparison will be made with retrospective cohort using unmonitored or conventional frozen section guided surgical excision for periocular BCC in our institute.

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 9221 0
Hong Kong
State/province [1] 9221 0
Hong Kong

Funding & Sponsors
Funding source category [1] 297551 0
Name [1] 297551 0
The Chinese University of Hong Kong
Address [1] 297551 0
The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, The People's Republic of China
Country [1] 297551 0
Hong Kong
Primary sponsor type
The Chinese University of Hong Kong
The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, The People's Republic of China
Hong Kong
Secondary sponsor category [1] 296561 0
Name [1] 296561 0
The Prince of Wales Hospital
Address [1] 296561 0
30-32 Ngan Shing Street, Shatin, NT., Hong Kong SAR, The People's Republic of China
Country [1] 296561 0
Hong Kong

Ethics approval
Ethics application status
Ethics committee name [1] 298646 0
Joint The Chinese University of Hong Kong -New Territories East Cluster Clinical Research Ethics Committee
Ethics committee address [1] 298646 0
Joint CUHK-NTEC Clinical Research Ethics Committee
8/F, Lui Che Woo Clinical Sciences Building,
Prince of Wales Hospital
Shatin, Hong Kong
Ethics committee country [1] 298646 0
Hong Kong
Date submitted for ethics approval [1] 298646 0
Approval date [1] 298646 0
Ethics approval number [1] 298646 0

Brief summary
Purpose of Research
To introduce the use and investigate the safety and efficacy of Mohs Micrographic Surgery(MMS) in the treatment of periocular basal cell carcinoma (BCC) in Hong Kong.

Expected Duration
Participants are seen by the ophthalmologist and we will try to arrange the removal of the mass within next 2 weeks. Participants will be seen at postoperative week 1, 4, 12, 26 and 52 to look for any surgical complication and recurrence.

Main Outcome and Measures
Clinical and histological characteristics of tumors, layers of MMS procedures, complications and biopsy-confirmed recurrence at the same location.

Potential Risks or Discomfort
There may be some discomfort during the procedure. Excision of tumor will leave a scar and may damage certain important structure around the eye. Participants' eyelid may droop or may not close well. There is always a risk of recurrence or metastasis of the tumor.

Potential Benefits
MMS offers the best chance of cure and lowest recurrence rate as the treatment of skin cancer in other parts of the body. Overseas evidences also favor the use of MMS in the treatment of periocular BCC.
Trial website
Trial related presentations / publications
Public notes
Attachments [1] 2060 2060 0 0
Attachments [2] 2061 2061 0 0
/AnzctrAttachments/373676-Approval letter.pdf (Ethics approval)
Attachments [3] 2062 2062 0 0
/AnzctrAttachments/373676-Patients consent Chinese&English ver..docx (Participant information/consent)

Principal investigator
Name 77762 0
Dr Chong Kam Lung Kelvin
Address 77762 0
DOVS, 4/F, Hong Kong Eye Hospital, 147K Argyle Street, Mong Kok, Kowloon, Hong Kong SAR
Country 77762 0
Hong Kong
Phone 77762 0
Fax 77762 0
Email 77762 0
Contact person for public queries
Name 77763 0
Mr Yeung Lok Yiu
Address 77763 0
DOVS, 4/F, Hong Kong Eye Hospital, 147K Argyle Street, Mong Kok, Kowloon, Hong Kong SAR
Country 77763 0
Hong Kong
Phone 77763 0
Fax 77763 0
Email 77763 0
Contact person for scientific queries
Name 77764 0
Prof Chong Kam Lung Kelvin
Address 77764 0
DOVS, 4/F, Hong Kong Eye Hospital, 147K Argyle Street, Mong Kok, Kowloon, Hong Kong SAR
Country 77764 0
Hong Kong
Phone 77764 0
Fax 77764 0
Email 77764 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary