Photodynamic Infrared Spectroscopy (PDIS)

Circulating Tumor Cell Testing & Therapy

Photodynamic Infrared Spectroscopy

A state-of-the-art screening and treatment procedure that offers an opportunity for cancer patients to prevent tumor metastasis, Photodynamic Infrared Spectroscopy (PDIS) combines light therapy and infrared technology to detect and subsequently target circulating tumor cells.

Circulating tumor cells, or CTCs, are cancer cells that escape their primary tumor, circulating the bloodstream until they colonize and compromise additional organs. These cells are often the cause of metastasis; when patients and doctors believe that traditional procedures have successfully removed cancer only to find another tumor years later, lingering CTCs are the culprit.

Although blood screening procedures to monitor the presence of CTCs are available in many labs around the world, these tests are limited in accuracy. Typically based on the analysis of only 10-20 ml of blood, current sample sizes are too small to reflect the pro-metastatic conditions of the entire body, while transportation to distant labs and hours of necessary analytical workup often introduce additional errors. Furthermore, most CTC genetic variants go through a cellular transition phase (from epithelial to mesenchymal) prior entering the bloodstream; these variants are virtually undetectable by blood screening tests.

PDIS is the first revolutionary step in controlling the process of metastasis, possessing the ability to screen, detect, and treat CTCs even in their mesenchymal variant form. We are proud to offer our patients access to such advanced technology at Hope4Cancer Treatment Centers.

How it Works

  1. Screening patients receive a catheter infused with indocyanine green (ICG), a non-toxic sensitizer agent, inserted as an intravenous drip for 30-45 minutes.
  2. A fiber optic laser is inserted through the catheter, utilizing infrared light.
  3. A spectroscopy unit and probe screens 5-6 L of blood volume over approximately 17 minutes.
  4. Any CTCs detected by the probe will cause the spectrograph monitor to peak.

If no CTCs are found, the determined risk of metastasis is extremely low. If even one cell is located, PDIS can then be directed specifically for treatment via Photodynamic Therapy using a low-level infrared laser on the wrist to penetrate blood in the veins closest to the skin. When passing CTCs containing ICG are exposed to the light, a sequence of reactions that generate  reactive oxygen species is triggered inside the tumor cells, initiating cancer cell death.

About ICG and Sensitizer Agents:

ICG along with other photodynamic sensitizer agents used at Hope4Cancer are completely safe for patients. Sensitizers do not have “dark” toxicity; in other words, they are controlled and activated only when exposed to their specific light or sound frequency. Upon activation, an “explosion” of reactive oxygen is released, driving cancer cells to death via apoptosis or necrosis. As a result of the Enhanced Permeability and Retention (EPR) effect, a natural self-protective mechanism possessed by all healthy cells, only cancer cells are affected by our sensitizer agents. Following receipt of a sensitizer agent, a mandatory waiting period is fixed to allow any healthy cells that have come into contact with the substance ample time for rejection.

Complementary Therapies

PDIS also works in tandem with and is supported by other treatments offered at Hope4Cancer under the 7 Key Principles of Cancer Therapy. Oxygen therapy in particular can be beneficial to patients undergoing PDIS, as it improves oxygen levels used to react with the sensitizer. Hyperthermia has also demonstrated a significant complementary effect for its ability to activate the immune system and weaken cancer cells.

Patient Experience

PDIS is minimally invasive to patients at most and completely non-invasive at best. PDIS has no known side effects and is a non-painful procedure.

Why PDIS?  

  • Confirmation — PDIS can evaluate the efficiency of treatment and ensure post-surgery patients that no circulating tumor cells are present in the blood
  • Reassurance — Patients with a localized tumor that display no activity elsewhere on CAT scans can use PDIS to avoid metastasis risk.
  • Prevention — Individuals with a high risk of cancer in the family can use PDIS to proactively screen for CTCs before they colonize.
  • Therapy — Patients who find CTCs through PDIS can use the procedure subsequently to destroy remaining cancer cells in the bloodstream.

Interested in learning more about PDIS? Click Here to contact our admissions team or call us at: 1-888-544-5993 or 1-619-669-6511

Request a Free Consultation

Regardless of your situation, we believe there is HOPE!

Let’s Talk

We understand that you may have many concerns right now.
Our admissions counselors are happy to help you find the answers you need.
Get a FREE private consultation call today.

What To Expect


Fill out a secure and confidential form so we can get to know you a little better before the call.

– Less than 5 min to complete.


One of our admissions counselors will call you quickly to lend support and answer any questions that you may have about Hope4Cancer.