The Importance of Accurate Diagnosis and Multimodality Therapy for Pancreatic Cancer

Pancreatic cancer (adenocarcinoma) develops from the cells lining the pancreatic duct (duct or ductal cells), which are involved in processing and transporting digestive enzymes through the pancreas to the intestine to aid in digestion of food (especially fats). Transformation of a duct cell into a cancer is a complicated process characterized by a number of genetic mutations.

These mutations are an area of active investigation in the quest for a technique for early diagnosis and more effective therapies that target the molecular profile of the cancer. We are in the process of developing a pancreatic cancer research unit at the Medical College of Wisconsin, which will be based on the study of human cancers removed during biopsy procedures and with surgery. 

We have compiled a series of illustrations and CT scan images showing the staging of pancreatic cancer as well as some surgical illustrations. 

Staging Pancreatic Cancer

At the time of diagnosis, there is often confusion (on the part of patients and physicians) regarding how to stage the disease, whether or not the pancreatic tumor can be surgically removed, and the role for chemotherapy, chemotherapy combined with chemoradiation and how to combine chemotherapy, radiation and surgery in the most effective way. If surgery is performed, it is important that the surgeon be prepared to do a more extended operation involving the adjacent blood vessels (superior mesenteric vein, portal vein). The following tables provide guidelines for staging and treatment and were developed by me and my colleagues at M. D. Anderson Cancer Center over the last decade.

The following is a Clinical/Radiographic Staging System used for Adenocarcinoma of the Pancreatic Head based on high quality computed tomography (CT) imaging (see accompanying illustrations). The American Joint Commission on Cancer (AJCC) has established a four tier staging system for most solid tumors. In general, stages I and II are able to be surgically excised, stage III is localized, but usually not able to be surgically excised, and stage IV refers to cancers that have spread to other parts of the body.

Clinical Stage of disease AJCC Stage Tumor-Vessel Relationship on Computed Tomography
  SMA Celiac Axis **CHA SMV-PV
*Resectable (all 4 required to be resectable) I / II Normal tissue plane between tumor and vessel Normal tissue plane between tumor and vessel Normal tissue plane between tumor and vessel Patent (may include tumor abutment or encasement)
Borderline Resectable (only 1 of the 4 required) III abutment abutment Abutment or short segment encasement May have short segment occlusion if reconstruction possible
Locally Advanced (only 1 of the 4 required) III encasement encasement Extensive encasement with no technical option for reconstruction Occluded with no technical option for reconstruction

 


Abbreviations: CHA, common hepatic artery; SMV-PV, superior mesenteric vein-portal vein confluence

Definitions: abutment, ≤180° or ≤ 50% of the vessel circumference; encasement, >180° or > 50% of the vessel circumference

*Assumes the technical ability to resect and reconstruct the SMV, PV, or SMV-PV confluence when necessary. Others may consider tumor-vein abutment/encasement which results in deformity of the vein as borderline resectable.

**Assumes normal vascular anatomy; for example, encasement of the CHA is not a limitation in performing a whipple procedure when there is an uninvolved replaced right HA arising from the SMA.

The following table presents a general treatment schema used to guide stage-specific therapy for patients with adenocarcinoma of the pancreas.

 

 

 

Clinical Stage of disease AJCC Stage Treatment Options
*Resectable I / II
  1. Protocol-based, stage-specific neoadjuvant therapy
  2. Off-protocol neoadjuvant therapy (usually gemcitabine-based chemoradiation)
  3. Surgery followed by protocol-based adjuvant therapy for patients who have undergone an R0/R1 resection
Borderline Resectable III
  1. Protocol-based, stage-specific multimodality therapy
  2. Off-protocol therapy usually consisting of a gemcitabine doublet followed by chemoradiation and surgery (if no disease progression)
Locally Advanced III
  1. Protocol-based stage-specific multimodality therapy
  2. Off-protocol chemoradiation if pain is uncontrolled
  3. Off-protocol systemic therapy followed by chemoradiation (if no disease progression following systemic therapy)
Metastatic IV
  1. Protocol-based systemic therapy
  2. Off-protocol systemic therapy
  3. Best supportive care

 


Definitions:

 

 

 

 

  • Resectable disease: the tumor can be surgically excised 
  • Borderline resectable disease: the tumor may be surgically excised after chemotherapy and chemoradiation if the patient tolerates the treatment well and there is evidence of tumor response
  • Locally advanced disease: the tumor is not able to be surgically excised and in general, it is felt that surgery will never be possible.
  • Metastatic disease: the tumor has spread (through the blood stream or in other ways) to other parts of the body, most commonly the liver, abdominal cavity and occasionally, the lungs.