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Flashcards in Surgical Oncology Deck (48)
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1
Q

What 5 types of oncology surgery are available?

A
  1. Biopsy (diagnosis)
  2. Resection for cure (definitive excision)
  3. Palliation (remove clinical signs)
  4. Debulking (cytoreductive therapy)
  5. Prevention of neoplasia
    > should be defined before surgery
2
Q

Which sites should be biopsied for stagin?

A

T- tumour
N- local lymph node
M- distant metastasis

3
Q

When should you biopsy?

A
  • if outcome would change the treatement plan (Sx v chemo v radio)
  • extent of treatment (conservative v aggressive)
  • if owners decision would be affected (staging, grading)
  • if lesion is in difficult area (head and neck, distal limb)
4
Q

When is biopsy not indicated?

A
  • if treatment plan would not be changed (mammary masses, single large lung mass)
  • no change in owners willingness to treat (chest wall /limb sarcoma resection)
  • if biopsy is difficult (CNS, SI, thyroid)
5
Q

What information can be gained from a biopsy?

A
  • Definitive diagnosis of neoplasia (Neoplasia vs inflammation vs other)
  • Aggressiveness of neoplasia (Benign vs malignant)
  • Cytologic type of neoplasia (Round cell vs epithelial vs mesenchymal)
  • Histologic features (Definitive diagnosis of histological type)
  • Grade of tumour (Evaluation of metastases)
  • Lymph nodes/Distant metastases
6
Q

What types of biopsy are possible?

A
> Needle
-FNA
- Core (eg. Trucut)
> Incisional
- Surgical
- Grab
- Punch
> Excisional
7
Q

What should be avoided directly onto tissue when making an excisional biopsy?

A

Diathermy

8
Q

What should biopsies be stored in?

A

10% formalin

9
Q

What is the aim of prophylatctic surgery?

A

Reduce the incidence of some tumours or the recurrence rate after treatemnet

10
Q

What types of tissues may be removed prophylactically?

A

Normal (eg. gonads)

Abnormal (eg. pre-malignant changed tissues in SCC)

11
Q

Is OHE indicated alongisde removal of mammary tumours?

A

> controvesrsial

  • means you know any recurrence is malignant and not primary benign tumour
  • you can start aggressive treatment sooner
12
Q

Is removal of cryptorchid testes advocated?

A
  • risk of surgery = risk of developing tumour in testicle

- controversial

13
Q

What is the aim of definitive excision?

A

Use of surgery without adjunctive therapy for a complete cure
- although not 100% cells may be removed, immune system may finish the job

14
Q

When is definitive excision indicated?

A
  • localised disease

- occasionally regional mets

15
Q

What must be removed if excising a tumour?

A
  • margins in all dimensions (including deep)

- all incisional biopsy tracts

16
Q

Why is it so important for the 1st surgery to be successful?

A
  • regional anatomy normal
  • less seeding
  • most active and aggrrsive cells are at periphery, dirty margins leave most aggressive cells
  • less normal tissue making closure more difficult
17
Q

What should be carried out pre-op as preparation?

A
- Plan excision & reconstruction
• Clip a wide area
• Plan margins & stick to them
• Plan reconstruction – Plan A & Plan B (redundancy in
body systems – what can you throw away?)
- Anticipate problems with the wound
• Delayed healing
• Movement
• Increased wound infection
-Plan analgesia protocol pre-op
• Concerns about adequate analgesia should NOT
dictate whether surgery is performed
18
Q

How can contamination be minimised during surgery?

A

Avoid entering the pseudocapsule
• Contains tumour cells
Manipulate tumour gently
• Stay sutures, tissue forceps
Isolate tumour from body cavity
• Isolate with laparotomy sponges
Resect adhesions between tumour & normal tissue
• Adhesions may represent tumour invasion
Lavage the surgery site
• Tumour cells adhere via specific receptors – so little use
• BUT removes blood, necrotic tissue, foreign material
Change gloves & instruments
• Avoid seeding the surgical wound

19
Q

Why is vein occlusion so important in onc surgery?

A
  • prevents embolic spread of tumour

- arteries first probably best plan

20
Q

Which LNs should be biopsied pre-op and during op?

A
  • regional LNs pre-op

- all grossly normal LNs during op

21
Q

When should LNs be excised at surgery?

A
  • LN positive for tumour & not fixed
  • LN grossly abnormal at surgery
  • LN intimately attached to excised tissue
  • If associated with therapeutic benefit
22
Q

When is LN removal not indicated?

A
  • LN fixed to”critical” adjacent tissue (Biopsy)

* If uncertain whether positive for tumour (Biopsy)

23
Q

What is the pseudocapsule?

A
  • zone of compressed tissue around tumour

- contains viable tumour cells so DO NOT CUT INTO !

24
Q

Types of excision?

A
  • Local
  • Wide local
  • Radical
    > radical local
    > compartmental
    > muscle group
    > amputation
25
Q

When is local incision indicated?

A
  • benign tumours and no local invasion (lipoma, histiocytoma, sebaceous adenoma)
  • preservation of local tissue ( CNS, thyroid adenoma)
26
Q

When is wide local excsision indicated?

A
  • benign/local invasion
  • malignancy/limited local invasion
    eg. 1cm SCC, benign oral tumour
    2-3cm MCT, ST
27
Q

What is radical excision?

A

margins extedned into fascial planes undisturbed by tumour growth (1 or 2 fascial planes beyond gross tumour)

28
Q

What are the 4 types of radical excision?

A
  1. radical local
  2. compartmental
  3. muscle group
  4. amputation
29
Q

egs of tumour when radical excision is indicated?

A
• Invasive sarcomas of the abdominal or chest wall
Chest or abdominal wall resection
• Invasive carcinoma of the nasal planum
Nasal planum resection & premaxillectomy
• Invasive tumours involving eyelids
Excision of eyelids & orbital contents
• Invasive orbital/periorbital tumours
Orbitectomy
30
Q

What is compartmental excisison?

A
  • tumour removed in a intact anatomic compartment

eg. invasive tumours in the limbs or trunk

31
Q

What is muscle group excision?

A
  • tumour removed along with the involved muscle
  • no breach of fascial plane, or breach which is excised
  • for small tumours involving muscle bellies
32
Q

When is amputation indicated?

A
  • Large tumours - other method not possible
  • If radical excision impairs function - bone/joint excision
  • Management of recurrences - disturbed fascial planes
33
Q

How should samples be prepared for histology?

A
>Anatomically relevant
• Lay out as in vivo +/- sutures
>Indicate margins of interest
• Closest to tumour
>Methods of marking margins
• Suture tag
• Paint with ink
• Draw a picture to orientate
> Provide a history
• Relevant & detailed
34
Q

What can post-op histopathology tell you about the tumour?

A

Histological type of tumour
• Confirms pre-operative knowledge of tissue type
Histological grade of tumour
• Mitotic index, differentiation, necrosis
Regional lymph node status - access
• Staging of disease (if inaccessible pre-operatively)
Margins – adequacy of excision
• Predicts local recurrence
Vascular or lymphatic invasion
• Predicts distant metastasis

35
Q

How may margin evaluation give incorrect results?

A

False negative
• Tumour present at margins - but not the one examined
False positive
• Tumour present - but edge examined is not a margin
Specimen incorrectly oriented

36
Q

What is the aim of cytoreductive surgery?

A
  • planned INcomplete excision of a tumour to improve the efficacy of other modalities
37
Q

Indications for cytoreductive surgery?

A
• Essential structures (CNS tumours)
• Surgical management of recurrences
Unknown tumour borders
• Local recurrence likely (SA distal limb)
• Highly malignant tumours
Vaccine-associated sarcomas
38
Q

What are the 3 main PROTOCOLS of adjunctive therapy?

A

> pre-op: to reduce tumour bulk prior to surgery eg. sarcomas
intra-op: to allow access to tumours eg. bladder
post-op: to treat small numbers of rapidly proliferating, well oxygenated cells eg. mast cell tumour

39
Q

What are the 5 main types of adjunctive therapy?

A
  • chemotherapy
  • radiation therapy
  • immunotherapy
  • hyperthermia
  • photodynamic therapy
40
Q

Indications for chemotherapy? What must be carried out prior to starting chemo?

A
  • treat invasive or metastatic tumours not completely
    removed by surgery
  • used before or after surgery
    > debulk >90% tumour before starting
41
Q

Potential complications associated with chemo?

A

-delayed wound healing,
vomiting, diarrhoea, nephrotox., bone marrow
suppression

42
Q

When can radiation therapy be used?

A

Before, during or after surgery
- shrink the tumour before or destroy any remaining
cells after surgery
- potential for early or late moist desquamation or
ulceration of tissues

43
Q

egs. of immunomodulatory therapy?

A
  • interleukins, cytokines, interferons, CSF, monoclonal
    antibodies
  • rapidly developing area of research to find very
    specific effect on tumours
44
Q

How is hyperthermia used in neoplastic treatments and what is it often combined with? Is this a common tx?

A
  • locally or systemically to destroy heat sensitive tumour cells
  • combined with chemo or radiation
    > NOT a very practical method currently
45
Q

Outline how photodynamic therapy can be used to destroy tumours

A

the use of various wavelengths of light to destroy
tumour cells
- sensitising agents given to the patient are taken up by
tumours cells
- the tumour is exposed to light causing a reaction with
the sensitising agent
- result is destruction of tumour cells

46
Q

Aims of palliative tx?

A

Surgery performed to improve quality of life, for pain
relief, improved function of the affected part, or to
eliminate life-threatening complications
• Consider balance between potential gain vs morbidity!

47
Q

INdications for palliative surgery?

A
  • Tumour with metastasis

- Complete excision impossible

48
Q

egs. of palliative surgery?

A
> Limb amputation for osteosarcoma
> Splenectomy for haemangiosarcoma
> Placement of a cystostomy catheter for
TCC
> Removal of ulcerated mammary tumours
> Mandibulectomy for oral melanoma