From the Guidelines
A rectal mass in a patient with acute myeloid leukemia (AML) should be promptly evaluated with proctoscopy, biopsy, and imaging to determine the cause and guide treatment, which may include systemic chemotherapy, local radiation therapy, or antimicrobial therapy, depending on whether the mass is a myeloid sarcoma, infection, or separate malignancy. The patient's treatment plan should be individualized based on their specific characteristics, such as age, cytogenetics, molecular genetics, and performance status 1.
Evaluation and Diagnosis
The patient should undergo immediate proctoscopy with biopsy of the mass for histopathological examination, immunohistochemistry, and flow cytometry to determine the cause of the rectal mass. Concurrent imaging with CT or MRI of the pelvis is essential to assess the extent of the mass and regional lymph node involvement.
Treatment Options
If the mass is confirmed as myeloid sarcoma (extramedullary AML), treatment typically involves systemic chemotherapy similar to the AML regimen, which may include cytarabine and anthracycline-based induction therapy, such as the "7+3" regimen, which consists of 7 days of standard-dose cytarabine and 3 days of daunorubicin 1. Local radiation therapy (typically 20-30 Gy) may be added for symptomatic relief or if the mass persists after chemotherapy.
Considerations
The prognosis depends on the underlying AML status, response to therapy, and whether the rectal mass represents a relapse or concurrent presentation with initial AML diagnosis. Extramedullary manifestations of AML can occur in various sites, including the gastrointestinal tract, and their presence may indicate more aggressive disease requiring intensified treatment approaches 1.
Treatment Algorithm
The treatment algorithm for AML, including the use of gemtuzumab ozogamicin, midostaurin, and other targeted therapies, should be considered in the context of the patient's specific characteristics and risk factors, as outlined in the ESMO clinical practice guidelines for diagnosis, treatment, and follow-up of AML 1.
Key Considerations
- Prompt evaluation and diagnosis are crucial to determine the cause of the rectal mass and guide treatment.
- Individualized treatment plans should be based on the patient's specific characteristics, such as age, cytogenetics, molecular genetics, and performance status.
- Systemic chemotherapy, local radiation therapy, and antimicrobial therapy may be used to treat the rectal mass, depending on the cause.
- Extramedullary manifestations of AML can occur in various sites, including the gastrointestinal tract, and may indicate more aggressive disease requiring intensified treatment approaches.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Case Report: Rectal Mass and AML
- The provided studies do not directly address the relationship between a rectal mass and Acute Myeloid Leukemia (AML) in a case report format.
- However, some studies discuss the management of rectal cancer 2, 3, 4 and the diagnosis and treatment of AML 5, 6.
- For rectal cancer, treatment requires an understanding of the presenting stage and location to provide oncologic sound treatment decisions 2.
- The management of locally advanced rectal cancer has evolved to a more personalized, multidisciplinary approach 3.
- Malignant rectal pain and tenesmus cause significant morbidity for cancer patients, but there is little evidence to guide management of these symptoms 4.
- In AML, bone marrow biopsy during induction chemotherapy can identify patients with resistant disease, but it may not be accurate in predicting complete remission 5, 6.
- A study found that bone marrow biopsy on day 6 of induction therapy for AML can identify only 50% of patients with resistant disease 6.
- Another study found that day 14 bone marrow biopsy has 82% sensitivity in predicting complete remission on day 28, but it has insufficient specificity in predicting failure of complete remission 5.