Download Basic principles of oncology

Basic principles of oncology
I amarasinghe MS FRCS
Surgical oncologist
Definition of a principle
A fundamental truth
That serves..
As a foundation…
For a chain of reasoning
Cancer documentation
• Risk factors
• Cancer families..3 types
No cancer in any generation
Assortment of cancers
Same cancer repeating…gene typing
• Knudsons two hit hypothesis
Investigating a patient with a primary
diagnosis of cancer
• Investigations to confirm diagnosis
• Investigations to detect spread
Investigation for spread
• Common inv such as CXR.us scan. CT .Mri.
Bone scans,mammography etc
Vs
• PETCT
Usefulness of whole body pet ct in
comprehensive oncological management
When used as a diagnostic tool
• 30% showed metastatic disease where CT was
inconclusive or negative
• In 20% it changed the management
completely
In diagnostic investigations
• Eg mammography combined with ultrasound
breast is 99% accurate.
• Triple assessment
• Core biopsy?
• Even tho fnac is less expensive ultimately as it is
non diagnostic it proves more cost effective to do
core via Trucut or VABB????
Principles of treatment of a breast
mass in a young girl
• Clinically benign mass on examination
• Reassure and dismiss????
Guidelines from American National
Cancer Institute
• Do a bilateral us of both breasts for
impalpable lesions
• If she wants follow up…do an fnac to exclude
early phylloides
• Follow up 6 monthly
• Be cautious over 40 years of age
Principle of trends in oncology
•
•
•
•
•
More and more towards organ preservation
Breast conservation
Volume replacement for tongue
Modified block dissections for nodes
Sentinel nodes for axilla and groin
Surgery for cancer
Address margins
Address regional spread
Margins…Point of contention
• 40 years of BCS
• The problem of Ipsilateral Breast Tumour
Recurrence (IBTR)
• Directly related to margins of surgical
excision.
Methods of assessing margins
• Frozen section outdated and laborious
• Imprint cytology
• Cavity margin shave assessment…good but
still re excision may occur
• technology..Margin probe..electromagnetic
.
device
Mico ct
How negative should a margin be?
• An meta analysis of 14,571 patients indicated
there was no statistically significant
difference of negative margins less than 1
mm in terms of local recurrence (int journal
surgical oncology 2012)
Problems of positive margins
• Further surgery
•
•
•
•
Cosmetic outcome impaired
Further health cost for repeat surgery
Emotional conflict for patient
Delays adjuvant therapy
• In the UK >70% opt for BCS rather than mastectomy
• Due to the screening program
Finally…guidelines after 40 years
• Combined consensus
• American society of radiation oncologists
ASTRO
• Society of surgical Oncology SSO.(.annals of
surgical oncology)
Recommendations
• Positive margins are defined as ink on
invasive cancer or DCIS
• Associated with at least two fold increase in
IBTR (Ipsilateral breast tumor recurrence)
• This increased risk is NOT NULLIFIED BY
DELIVERY OF BOOST
SYSTEMIC THERAPY
FAVOURABLE BIOLOGY
Summary
•
•
•
•
•
•
40 years of BCS globally
Aim must be to avoid IBTR
Adequate Margin mandatory.1 cm or >
However recurring positive margins still 5-17%
Advent of oncoplastic flaps
Guidelines by ASTRO and SSO indicate only ink on
tumor significant for local recurrence.
• EIC, young age, Invasive lobular., close margins
not an indication for re excision.
Surgery for advanced cancer
• Always biopsy for markers
• Consider cytoreductive surgery to enhance
subsequent treatment with adjuvant therapy
Markers on tumors must be done at all
stages of presentation
• Absolutely essential for overall treatment
• Eg Basic markers ER PR .Her2
• Advanced molecular markers ki-67
proliferation index
• Genetic markers
chemotherapy
• Is systemic so can eliminate hidden tumor
burden
• Toxic side effects must be carefully but
positively addressed
Support is a fundamental need
• Needs to be very carefully evaluated
• Most complicated are single non religious
males….
• can lead to depression and suicide
• The most needy time is at the first recurrence
and the
terminal stage
• Can a clinician handle this????
Palliative care
• Needs tactful interaction on all fronts
• Main aim is control of Pain
• must understand the difference in prolonging
life and prolonging death
Thank you