Managing the Oral Health Complications of Chemotherapy

Nathaniel Treister, DMD, DMSc
Assistant professor of Oral Medicine at Harvard School of Dental Medicine and the chief of the divisions of Oral Medicine and Dentistry at Brigham & Women’s Hospital in Boston, Massachusetts

What are the oral complications of cancer therapy that hematologists/oncologists should be aware of?

The treatments for hematologic malignancies – chemotherapy, combinations of chemotherapy, or hematopoietic cell transplantation – are associated with a variety of oral complications. First and foremost is the risk of infection due to the profound immunosuppressive and neutropenic effects of chemotherapy. Ondotogenic infections are very common in the general population, and these infections can pose a significant risk in patients with hematologic malignancies undergoing myelosuppressive therapies.

Other oral infections commonly encountered in these patients include oral candidiasis, as well as infection with recrudescent oral herpes simplex virus infection (HSV-1). Oral candidiasis is a common superficial mucosal yeast infection that can be easily identified and diagnosed by a hematologist or clinical staff person and treated with appropriate antifungal therapy. While the majority of the adult population is asymptomatically seropositive for HSV-1, during the immunosuppression associated with cancer therapy, patients are at significant risk for viral reactivation and recrudescence. HSV-1 most commonly affects the lips but, it is common in this patient population for recrudescent ulcerations to develop inside the mouth and on any mucosal surface.

Mucositis, a very painful and often debilitating condition in which the mucosa of the mouth and throat becomes inflamed and ulcerated, is also a significant, non-infectious complication of cancer treatment that can limit the ability to eat and swallow.

Other potential complications of chemotherapy include dry mouth and taste changes – although these symptoms are highly variable and not well-defined. In addition, a number of new targeted cancer therapies are becoming more prevalent in the treatment of blood cancers – some of which have been associated with unique oral toxicities that have the potential to interfere with the delivery of care.

Aside from the pain and quality-of-life implications, there is also an associated increased risk of developing secondary oral squamous cell carcinoma in patients undergoing transplant – a very serious and potentially life-threatening complication.

Development of acute infections or other oral complications during cancer treatment can potentially lead to alteration or delays in therapy, hospitalization, and/or increased cost of therapy – all of which can affect treatment outcomes. As much as possible, obviously, we try to prevent these complications and to manage them as aggressively as possible to avoid a dose reduction or break in treatment. Sometimes, however, it’s unavoidable.

Are there any special considerations for patients undergoing hematopoietic stem cell transplantation?

Patients undergoing fully myeloablative allogeneic hematopoietic stem cell transplantation are at a very high risk for infection. Many transplant centers have formal dental screening programs to ensure risk reduction for all patients. The other major consideration with allogeneic HSCT patients is the development of oral graft-versus-host disease (GVHD). While the oral cavity is variably involved in acute GVHD, it is one the most frequently affected sites in chronic GVHD and a source of significant morbidity. Topical steroids can be highly effective in managing oral mucosal GVHD and associated symptoms.

GVHD can also have a devastating effect on the teeth due to salivary gland inflammation and dysfunction secondary to GVHD. Therefore, it is essential that patients return to their dentists for exams, cleaning, and radiographs within six to 12 months after HSCT. Oral GVHD may persist and require management for years after allogeneic HSCT. While some aspects of oral GVHD may be effectively managed by the hematologist-oncologist, referral to an oral medicine specialist may be necessary in more complex cases.

Also, because of the long-term risk of developing secondary oral malignancy, the oral mucosa needs to be routinely examined for any abnormalities or suspicious changes, even in patients that do not develop GVHD following transplant, or in patients who had oral GVHD with an otherwise resolved condition. Any abnormalities should be referred for biopsy.

What can hematologists/oncologists do to manage oral health complications in patients undergoing chemotherapy?

Throughout a patient’s cancer treatment, hematologists/oncologists should make a point to ask whether or not the patient is experiencing any oral symptoms or problems and examine the oral cavity routinely to assess for any abnormalities.

In some cases, antifungal therapy may be provided up front as prophylaxis, usually in the form of a topical agent (such as nystatin solution or clotrimazole troches); similarly, prophylactic antiviral therapy with acyclovir can reduce the risk of recrudescence. Some centers may also ask their patients to rinse with chlorhexidine mouthwash as an additional prophylactic measure to decontaminate the oral cavity.

Symptoms secondary to mucositis should be recognized and managed early and aggressively. Topical anesthetics and systemic analgesics are the mainstay of pain management. Nutritional counseling may also be indicated for patients with severely limited oral intake. In case of unclear or nonresponsive pathology, it is ideal to have an oral health specialist available for consultation.

How can the hematology/oncology team help mitigate the oral complications of cancer treatment?

First and foremost, the team – as well as the nursing staff and the patient’s dentist – can reinforce the importance of maintaining good oral hygiene before, during, and after cancer therapy. There has been some debate as to whether flossing the teeth is safe in a neutropenic or thrombocytopenic patient, but, as long as somebody is continuing with his or her standard home care, the general consensus is in favor of maintaining normal hygiene – flossing and brushing with a regular toothbrush and toothpaste.

Involving the dentist early on – prior to starting cancer therapy – is ideal; patients should visit their dentist for a checkup and examination to identify any dental infections or areas at risk for developing infections. These teeth should be treated definitively.

Having oral health expertise as part of the hematology/oncology team can greatly optimize patient care by reducing the risk of oral complications that arise. Of course, this may not be possible in smaller or community-based oncology centers. In smaller health-care settings, with good planning and foresight, the community dentist can play an active and effective role in their patient’s hematology/oncology care.