April 2004         

The patient is a 64 year old female with NonHodgkins lymphoma. A PET scan was ordered to evaluate disease progression with comparisons to previous PET scans.

History of Present Illness:
In October of 2003 the patient was diagnosed after presenting with abdominal cramps and bloating that had been occurring for several months. An EGD revealed a large gastric ulcer. A biopsy at this time showed diffuse large cell lymphoma which was strongly positive for CD20. A CT scan revealed thickening of the wall of the antrum of the stomach consistent with gastric lymphoma. A PET scan showed uptake in the wall of the anterior stomach and mild uptake in the mediastinal lymph nodes. A liver biopsy, performed because of elevated liver function tests, revealed mild hepatocellular reactive changes. Her presentation was unique in that she did not have the classic symptoms of lymphoma. She did not have fever, weight loss or night sweats.

At this time the patient was started on Rituxan and CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy regimen. She received this monthly for 4 months. This was well tolerated with the exception of anemia and some mucositis. Unfortunately, follow up revealed that the lymphoma had not responded to the chemotherapy. A January 2004 PET image showed marked uptake in the stomach, mediastinum and bilateral hilar areas of the chest. Also present were numerous lesions in the liver. CT scan revealed an increase in the size of the gastric mass with infiltration of surrounding tissue.

The patient’s chemotherapy regimen was changed to DT-PACE (dexamethasone, thalidomide, cisplatin, doxorubicin, cyclophosphamide, etoposide). She is also receiving G-CSF (Neupogen) for neutropenia.    Plans were also made to harvest stem cells for future autologous stem cell transplant. 

Procedure:
The patient received diazepam 5 mg orally to decrease the muscle tone in the head and neck. She then received 720 MBq F-18 FDG via a central venous line. Ninety minutes after injection imaging was performed from the top of the head to the hips.

For image magnification click here

Findings:
Intense FDG uptake in the marrow and increased uptake within the spleen. Multiple FDG avid masses were present in the liver, which were increased in size from previous PET imaging. There is also a focal node in the periumbilical region (Sister Mary Joseph node). In addition there are multiple tiny FDG avid foci scattered throughout the abdomen and pelvis. Also seen is a large FDG avid mass involving the stomach. This has increased in size from previous images and there is also an increase in the SUV (standardized uptake value). Previously this mass had an SUV of 38.1 and it is now 61.9.

Teaching Point:

FDG-PET is increasingly being used to assess malignant tumors. However, leukocyte colony-stimulating factors (CSFs), which promote the expansion of hematopoietic bone marrow, have also been demonstrated to cause increased spleen and bone-marrow FDG uptake. G-CSF mediated FDG uptake in bone marrow is often indistinguishable from that caused by disseminated metastatic disease. However, the bone-marrow response to G-CSF decreases rapidly following the last CSF administration. Therefore, FDG-PET in patients receiving G-CSF should be delayed, when possible, until 5 days after the end of G-CSF therapy.

Hollinger EF. Alibazoglu H. Ali A. Green A. Lamonica G. Hematopoietic cytokine-mediated FDG uptake simulates the appearance of diffuse metastatic disease on whole-body PET imaging. Clinical Nuclear Medicine. 23(2):93-8, 1998 Feb.
 

Impression:
Interval worsening of disease with increase in size and SUV of multiple liver lesions. Multiple new foci scattered throughout the abdomen with a Sister Mary Joseph node present. Marrow involvement has increased in severity and is now homogenous with an SUV of 11.1. The gastric mass has increased in size and SUV as well.


Teaching Point:
The Sister Mary Joseph node is a firm, periumbilical nodule. It is generally associated with metastatic cancer within the abdomen and signifies a poor prognosis. It is named for a surgical assistant who worked under Dr. William Mayo from 1890 to 1915. While preparing patients for surgery she noted that the presence of an umbilical nodule usually indicated advanced cancer. It was named for her some years after her death.

 

 

© 2004 Nuclear Education Online

Case submitted by James Mikles, Cardinal Health, Fort Smith, AR
Images courtesy of Dr. Ronald Walker, UAMS Dept of Nuclear Medicine.