How do you manage a patient undergoing an allogeneic bone marrow transplant?

This question was submitted to us by a general dentist: How should we manage a patient undergoing an allogeneic bone marrow transplant?

Dr. Jeff Chadwick, at Princess Margaret Cancer Centre, Dental Oncology, Ocular, and Maxillofacial Prosthetics Group, provided a preliminary response to this question

The allogeneic bone marrow transplant (BMT) is a medical procedure that may be employed for the treatment of several hematologic malignancies including, but not limited to, aplastic anemia, myelodysplastic syndrome, acute and chronic leukemias and lymphomas. BMTs typically involve the insertion of a central venous catheter (CVC), high dose chemotherapy and, in some cases, total body irradiation, prior to the infusion of the related/unrelated donor stem cells. This procedure carries a significant risk of morbidity and mortality. Patients generally require a period of hospitalization in isolation for approximately four weeks for recovery during which time they will be pancytopenic.

The myeloablative therapy that patients receive for this procedure places them at risk for infection and with their sub-optimal neutrophil and platelet counts, dental care is not without risk. It is for this reason that patients who require a BMT undergo a thorough dental and radiographic examination to remove potential sources of infection. Active dental disease (periodontal disease, caries, periapical inflammatory disease) requires treatment and optimal oral health should be achieved before hospitalization to prevent peri/post-transplant complications, such as life-threatening septicemias. The duration of the immunosuppressed period post-BMT is variable and can be up to one year or more after the transplant during which time the patient may be suffering from the more typical adverse effects of their BMT/chemotherapy which include xerostomia, dysgeusia, mucositis, neuropathies and bacterial, viral and fungal infections. These patients may have their CVC in situ during this time and may require frequent transfusions or further intravenous drug therapy. For these reasons, safe dental care in the private office setting is variable and largely at the discretion of the provider.

Ideally, there should be no oral care delivered by a dentist during the peri-transplant and early post-transplant period, as all existing dental disease would have been eliminated or stabilized prior to transplantation. The patient, however, should continue to keep the oral cavity as sanitary as possible to help reduce the risk of infection and prolonged episodes of bleeding. In some cases, patients may be asked to discontinue the use of their toothbrush/dentifrice and floss and substitute them with a combination of a chlorohexidine mouth rinse/foam toothbrush to maintain their dentition during the early post-BMT period. Additionally, the patient’s medical oncologist may prescribe antiviral and antifungal medications to reduce the incidence of viral and fungal infections in the oral cavity. If the patient happens to develop the signs and symptoms associated with an odontogenic infection, they should be immediately assessed by a dentist. In most cases, supportive measures, such as antibiotics and analgesics, are employed until the patient’s pancytopenia resolves to a level that is reasonably safe for dental treatment.

Complications related to bone marrow transplantation include graft versus host disease (GVHD) and oral lesions secondary to opportunistic infections. Oral lesions of GVHD may have a significant impact on oral/dental health and the associated effects include xerostomia (which would predispose the patient to an increased risk of dental decay), atrophy of the gingiva and oral mucosal lichenoid lesions with or without ulceration. Additionally, an increase in the incidence of oral herpetic and human papilloma virus infections and candidiasis may also occur. If a diagnosis of GVHD were rendered, systemic medical therapy would include immunosuppressant agents, which may or may not necessitate the use of prophylactic antibiotics as per the current AHA regimen for dental procedures that will result in gingival bleeding.

If the patient recovers completely and is not being treated for GVHD, they can be seen in private practice with the caveat that the medical history is always updated and there is no recurrent disease or complication related to their disease. Vital information to consider before performing dental treatment on patients that have had a BMT should include (but is not limited to):

1. General Medical History/Medication History/Social History

2. Oncology History

• Original Diagnosis (including type, stage and prognosis)
• Date of Diagnosis
• Treatment Centre/Medical Oncologist
• Treatment delivered (Radiation/Chemotherapy/Surgery/BMT)
  • Type of surgery
  • Constituents and duration of chemotherapy
  • Type and date of BMT (autologous, matched related/unrelated, mismatch unrelated, syngeneic)
  • Type and duration/dose of radiation (# of fractions/# Gray [Gy])
• Any ongoing therapy
  • Maintenance chemotherapy
  • Presence of indwelling catheters (Hickman/PICC line, Port-a-cath)
  • Monitoring regimen with oncology team

3. Clinical history of current dental issues

• Subjective history of pain (which could be the result of an odontogenic issue, previous treatment OR malignant disease)/swelling/fever/temperature sensitivity/oral fetor
• Clinical/Radiographic examination

4. Current complete blood count (CBC) with special attention to platelet count and absolute neutrophil count (ANC).

It is at this point that the practitioner should consider the following if treatment is required:

1. Referral back to the Department of Dentistry at the original treatment site (if possible) for treatment, if the patient is not medically suitable for treatment outside a hospital environment.
2. Appointment day ANC greater than 0.50 x 10⁹/L
3. Appointment day platelets greater than 50 x 10⁹/L
4. Presence of a CVC in situ requiring prophylactic antibiotics as per AHA guidelines for procedures which result in gingival bleeding
5. Presence of GVHD
6. Immunosuppressant medications (anti-GVHD medications, steroids, additional/ongoing chemotherapy)
7. If teeth are restorable, the most appropriate restorative material should be utilized.
8. If a tooth has become infected and is not amenable to endodontic therapy (vertical fracture, exceptional canal anatomy, unrestorable), extraction may be considered with attention given to the following:

• Pre/post-extraction antibiotic prophylaxis (if ANC is low or CVC in situ)
• Platelet transfusion support (if extraction is absolutely required and platelets are less than 50 x 10⁹/L)
• Conservative surgical approach
• Post-operative use of chlorohexidine 0.12% rinse twice daily until mucosal coverage is achieved
• Vigilant, frequent, follow-up and monitoring of the healing process

Ideally, prior to the commencement of a BMT, the staff dentists will have meticulously examined patients for dental disease at their respective cancer centres based on the request of the referring oncologist. While there are many conditions that are commonly observed in private practice, any source of infection (including, but not limited to: caries, odontogenic, periodontal) must be treated prior to myeloablative therapy to reduce peri/post-transplant complications. Communication with the patient’s medical oncologist should clearly outline both the extent of dental disease as well as a treatment plan and timeline so the patient’s therapy can be scheduled accurately.

For dentate patients post-BMT, a rigorous oral hygiene and maintenance program is mandatory and includes more frequent follow-up, scaling, oral hygiene re-instruction as well as more frequent radiographic surveys. Patients may also be placed on a regimen of 1.1% neutral pH sodium fluoride gel treatment, using custom “mouth-guard” type trays on a daily basis. This will aid in the reduction of post-BMT decay secondary to xerostomia that can be induced by several aspects of treatment, such as total body irradiation, head and neck radiation, and chemotherapeutic and analgesic agents. This may continue indefinitely, but its use is normally limited to their more xerostomic periods which can last anywhere between 6 and 18 months after their transplant. Additionally, it should be noted that this particular patient population is substantially more susceptible to the development of secondary malignancies, which include squamous cell carcinomas of the skin and oral cavity, myelodysplastic syndrome and post-transplant lymphoproliferative disease. Special care should be taken during examinations to detect any oral evidence of secondary malignancy (gingival infiltrates, unexpected excessive bleeding during dental procedures), which may be made more difficult to recognize/differentiate in the presence of GVHD. In many cases, once a patient has completed cancer treatment, achieved normalized blood counts and has recovered from the more acute adverse effects of their therapy, if medically stable, they will be referred back to their general dentist for regular care.

Do you have any particular question on this topic? Do you have any comments or suggestions? Email us at oasisdiscussions@cda-adc.ca

You are invited to comment on this post and provide further insights by posting in the comment box which you will find by clicking on “Post a reply“ below. You are welcome to remain anonymous and your email address will not be posted.