No, I would not order an Oncotype DX assay for this patient. I don’t believe the information from the Oncotype DX assay would be relevant for a patient with T4 disease, who we know has an added risk and will gain some benefit with FOLFOX, based on the MOSAIC trial and others.

For patients with T4, node-negative tumors, unless they had contraindications to adjuvant therapy I would generally recommend treatment. For this 60-year-old patient with Grade II, MSS T4N0 disease, I would recommend FOLFOX as adjuvant systemic therapy.

Depending on the depth of disease invasion, I may order an Oncotype DX assay. In this clinical situation some patients may want some additional information in order to consider adjuvant therapy. I have had patients who did not wish to receive treatment but were interested in an overall risk assessment.

If the Oncotype DX assay results classify the disease as high risk, I will discuss oxaliplatin therapy with the patient if he or she has a good performance status and is able to receive adjuvant therapy. However, a patient with Stage II disease at average risk will probably gain no additional benefit or significant benefit from adding oxaliplatin. Overall, it’s hard to be dogmatic about it because of the level of evidence we have. Part of the problem with the Oncotype DX assay is that it is not predictive.

I explain to patients with T4 disease that they are at higher risk and that therapy cannot guarantee a reduction in the likelihood of developing metastatic disease. In this scenario, I would lean more toward considering treatment with an oxaliplatin-based regimen. Then I would discuss the available modes of administration, oral or intravenous, as some patients have strong opinions about this.

I would not order an Oncotype DX assay in this scenario. The results would not affect my treatment decision. Given the MOSIAC trial data, I’m not particularly inclined to administer oxaliplatin routinely in this patient population.

For a patient with T4b disease where the tumor is invading an adjacent structure, I would administer adjuvant therapy. For patients with T4a disease, I’m “on the fence” and do not feel strongly about adjuvant therapy, although I will tell them that their risk is slightly increased. Often, I would gauge the patient’s preference.

For the patient with T4b disease, my treatment decision has evolved over time. I used to administer FOLFOX exclusively for patients at higher risk. Now I am a little more “on the fence” given the update on the MOSAIC trial, which did not demonstrate a survival benefit with FOLFOX versus 5-FU/leucovorin. I believe these results bring into question the role of oxaliplatin in high-risk Stage II disease. So I’m increasingly treating with 5-FU/leucovorin without oxaliplatin, although I have administered capecitabine in some cases.

In this situation I would consider ordering the Oncotype DX assay but would inform the patient of what information the Recurrence Score is likely to provide in terms of the range of likely relapse. If this additional information would make a difference in the patient’s treatment decision-making, I would order the test.

Because this patient has higher-risk disease, I would discuss with the patient the possibility of adjuvant therapy with FOLFOX.

Because I do not use the results of the Oncotype DX assay in my treatment decisions, I would not order the test for this patient.

For a patient with T4a or T4b disease, I would administer FOLFOX. For patients with Stage II disease, I consider high-risk factors such as T4b disease. If patients are otherwise reasonably healthy and have an appropriate life expectancy of 8 or 10 years and longer, then I treat as I would Stage III disease and I use an oxaliplatin-based regimen.

I would order an Oncotype DX assay only if the patient were reluctant to receive FOLFOX therapy. With the test result, I may be able to provide additional information to guide the patient’s treatment decision-making. Then I might tell the patient that his or her disease has a risk of recurrence of 25% to 30% and urge the patient to receive therapy. If the risk of recurrence is low, then I might say “don’t bother” with treatment. The Oncotype DX assay Recurrence Score provides a number that patients can focus on.

For a patient with T4N0 disease, I would generally administer FOLFOX.

This would be a good setting in which to order an Oncotype DX assay.

My treatment choice will be FOLFOX or CAPOX in about two thirds of the cases. My recommendation will be capecitabine alone or 5-FU alone in about a third of such cases. My treatment decision will be based on the patient’s preference and level of fitness. I have a preference for capecitabine with or without oxaliplatin in this scenario.

I would not order an Oncotype DX assay for this patient and I would not administer any adjuvant therapy in this situation.