What is the basics of surgical oncology?

Basics of Surgical Oncology

Core Principles and Definition

Surgical oncology is a specialized discipline that combines expert surgical technique with comprehensive oncologic knowledge, requiring surgeons to function as both technical operators and oncologists in the multidisciplinary management of cancer patients. 1

The specialty encompasses three fundamental pillars:

• Surgical expertise in performing complex cancer operations with sound judgment regarding operation selection 2
• Multidisciplinary integration to coordinate surgery with systemic therapies and radiation 1
• Long-term oncologic management including disease surveillance and participation in clinical research 1

Fundamental Surgical Principles

Resection Standards

Complete tumor removal with adequate margins (R0 resection) represents the cornerstone of curative surgical oncology. 3

Key technical requirements include:

• En-bloc resection of the primary tumor with surrounding normal tissue 3
• Removal of regional lymphatic drainage and associated vessels 4
• Preservation of function whenever oncologically safe 4
• Avoidance of tumor spillage during dissection 4

Margin Assessment

Surgical margins must be:

• Grossly negative at the time of resection 4
• Microscopically confirmed by pathology 4
• Adequate for tumor type (varies by cancer site and biology) 4

The surgical procedure should not be modified based on response to preoperative therapy except when tumor progression mandates more extensive resection. 4

Resectability Determination

Defining Unresectable Disease

Unresectability is determined when surgeons cannot remove all gross tumor on anatomic grounds or when local control cannot be achieved even with adjuvant radiotherapy. 4

Anatomic criteria for unresectability include: 4

• Dense involvement of cervical vertebrae or prevertebral fascia
• Encasement of major vessels (≥270° circumferential involvement of carotid artery)
• Extension to skull base with cranial neuropathy
• Direct invasion of mediastinal structures
• Brachial plexus involvement

Distinguish unresectable tumors (anatomically impossible) from inoperable patients (medically unfit for surgery) and those who refuse surgery. 4

Surgical Expertise and Volume

High-volume cancer centers and surgical specialists demonstrate superior outcomes for complex or advanced cancers. 1

Surgery should be performed by: 4, 5

• Surgeons with extensive oncologic experience
• Teams capable of complex reconstruction
• Centers with multidisciplinary infrastructure
• Facilities offering rehabilitative services

For adolescent and young adult (AYA) patients, surgery must be performed in high-volume centers by surgeons with specific expertise in this population, with access to rehabilitative services to preserve function. 4

Multidisciplinary Integration

Preoperative Evaluation

All patients must be evaluated by a surgical oncologist before any treatment to ensure proper staging, assess resectability, and plan potential surgical salvage if initial treatment is nonsurgical. 4

The surgical oncologist's preoperative role includes: 4

• Reviewing adequacy of biopsy material
• Confirming staging and imaging interpretation
• Excluding synchronous primary tumors
• Assessing baseline functional status
• Developing prospective surveillance plans

Treatment Coordination

Multidisciplinary evaluation and treatment must be coordinated and integrated prospectively by all modalities involved in patient care. 4

Critical coordination points include: 1, 6

• Type and timing of surgery after neoadjuvant therapies
• Integration with systemic treatment schedules
• Sequencing with radiation therapy
• Management of treatment-related complications

Special Considerations by Patient Population

Adolescent and Young Adult Patients

AYA patients may tolerate more intensive therapies than older patients due to fewer comorbidities, and dose-intensive regimens should be considered when evidence supports improved outcomes. 4

Unique considerations include: 4

• Body development effects: Adolescent bodies still developing may be more affected by extensive procedures
• Limb-sparing surgery: Feasible for most extremity sarcomas and osteosarcomas with modern techniques
• Fertility preservation: Critical consideration requiring preoperative counseling
• Functional preservation: Essential given long life expectancy

Comorbidity Assessment

Comorbidity is a strong independent predictor for mortality in cancer patients and must be documented to facilitate optimal treatment selection and prognostic estimates. 4

Use validated indices: 4

• Adult Comorbidity Evaluation-27 (ACE-27) for head and neck cancer
• Charlson index for general assessment
• Kaplan-Feinstein index and modifications

Site-Specific Surgical Principles

Breast Cancer

Standard surgical approach includes: 4

• Wide excision with negative margins
• Sentinel lymph node biopsy or axillary dissection as indicated
• Coordination with radiation therapy planning
• Integration with systemic therapy timing

For DCIS, surgical treatment should be based on multidisciplinary guidelines from ACR, ACoS, CAP, and SSO. 4

Colorectal Cancer

Standard treatment comprises excision of primary tumor with safe margins and excision of vessels and associated mesocolon containing lymphatic channels and nodes. 4

Technical requirements: 4

• Median laparotomy for adequate exposure
• Liver examination and sampling of suspicious masses
• En-bloc resection if neighboring organs involved
• Effective anastomosis requiring good bowel preparation and maintained vascular supply

Ovarian Cancer

Surgery should only be undertaken by teams able to offer a multidisciplinary approach and should include complete staging in early disease or maximal cytoreduction in advanced disease. 4

Complete staging consists of: 4

• Peritoneal cytology or lavage
• Complete abdominal exploration
• Infracolic omentectomy and appendicectomy
• Pelvic and para-aortic lymph node assessment
• Routine peritoneal biopsies

The volume of residual disease after initial surgery is of prognostic value, with complete excision providing the best outcomes. 4

Head and Neck Cancer

Primary tumor resection should be considered surgically curable by wide excision using accepted oncologic principles, with the goal of removing all gross tumor with adequate tumor-free surgical margins. 4

Critical elements: 4

• Evaluation by H&N surgical oncologist before any treatment
• Coordination with reconstructive surgeons
• Access to prosthodontists and physiatrists
• Neck dissection as indicated by nodal status

Bone Metastases

Spinal Metastases

Surgery for spinal metastases involves evaluating neurological risk, mechanical instability, number of metastases, patient condition, and expected survival using validated prognostic scores. 4

Surgical objectives include: 4

• Fixation to improve instability and pain
• Decompression to relieve spinal cord compression
• Combination approaches as needed
• Rarely, complete tumor resection for renal or thyroid cancer

For metastatic epidural spinal cord compression (MESCC), standard treatment combines surgery with postoperative fractionated radiotherapy. 4

Non-Spinal Metastases

For patients with prolonged expected survival, arthroplasty should be considered due to superior long-term functional outcomes; for shorter survival, simpler surgical osteosynthesis may be recommended. 4

Surgical Complications

Oncologic surgery carries high morbidity including hemorrhage, infections, thromboembolic complications, and risk of paraplegia, which can delay systemic treatment initiation and compromise survival. 4

Mitigation strategies: 4

• Appropriate interval between surgery and systemic treatment
• Preoperative embolization for highly vascularized metastases (kidney, melanoma, thyroid)
• Embolization ideally performed day before or day of surgery

Pathologic Evaluation

Essential Pathology Elements

The surgical pathology report must contain a synoptic database with multi-parameter tumor information to inform the clinical team. 4

Required elements include: 4

• Precise tumor location and laterality
• Presence/absence of capsular rupture or exophytic vegetations
• Histological type and grade
• Extension to adjacent organs or lymph nodes
• Quality of excision margins
• Cytology results from ascites or peritoneal lavage

Immunohistochemistry

For tumors of unknown origin or when differentiating primary from metastatic disease, a directed panel of immunohistochemical assays increases diagnostic accuracy. 4

Key markers: 4

• TTF-1 for lung adenocarcinoma (positive) vs. metastatic disease
• CK7/CK20 patterns for origin determination
• CDX-2 for colorectal origin
• Organ-specific markers (PSA, thyroglobulin) as indicated

Quality of Life Considerations

Health-related quality of life issues are paramount in surgical oncology, as cancer and its treatment affect basic physiologic functions, senses, and uniquely human characteristics. 4

Patient-completed validated scales should be used to measure quality of life, with disease-specific instruments providing the most relevant information. 4

Surgical planning must consider: 4

• Impact on basic functions (eating, breathing, speaking)
• Effects on appearance and social interaction
• Long-term functional outcomes
• Rehabilitation potential

Treatment Intensity in Young Patients

Selected AYA patients may tolerate more intensive therapies than older patients due to fewer comorbid conditions, and dose-intensive regimens should be considered when evidence supports improved outcomes for specific malignancies. 4

Every attempt should be made to maintain dose intensity unless contraindicated, as dose reductions should be based on avoiding severe, irreversible organ damage rather than reversible toxicities. 4

Emerging Concepts

Oligometastatic Disease

Extended surgical indications are being tested for oligometastatic disease in entities like pancreatic and gastric cancer within randomized controlled trials. 6

Metastasectomy has long been established for colorectal cancer and is being evaluated for other tumor types. 6

Organ Preservation

Clinical complete remission after total neoadjuvant therapy presents new challenges, with organ and function preservation increasingly considered but should only be performed within clinical trials until patient stratification enables identification of those for whom this approach is oncologically safe. 6

This applies particularly to: 6

• Locally advanced rectal cancer
• Esophageal cancer
• Other sites with excellent response to neoadjuvant therapy