Ductal Carcinomain-situ of the breast detected by [F-18] fluorodeoxyglucose positron emission tomography

Ductal carcinoma in situ and ductal carcinoma in situ with microinvasion: correlation of FDG uptake with histological and biological prognostic factors

BACKGROUND

Several studies investigated the correlation between the intensity of fluorodeoxyglucose (FDG) uptake and some histological and biological characteristics in breast cancer. Ductal carcinoma in situ (DCIS) is generally thought to be a precursor lesion of invasive breast cancer. The aim of this study was to assess the correlation between FDG uptake values on positron emission tomography/computed tomography (PET/CT) with histological and biological prognostic factors in DCIS and ductal carcinoma in situ with microinvasion (DCIS-Mi).

MATERIALS AND METHODS

PET/CT images for initial staging of confirmed DCIS and DCIS-Mi patients, taken between July 2004 and December 2009, were reviewed retrospectively. Maximum standardized uptake values (SUVmax) and tumor background count density ratio on PET/CT were compared with tumor characteristics. Histological and biological prognostic factors included tumor size, nuclear grade, Van Nuys Prognostic Index, estrogen receptor, progesterone receptor, HER2, and Ki-67 index.

RESULTS

In total, 87 lesions from 83 patients (all females; mean age 51 ± 9 years) were studied. The Van Nuys Prognostic Index group was 1 in 25 lesions, 2 in 36, and 3 in 26. On statistical analysis, significant differences in SUVmax and tumor background count density ratio were seen between the Van Nuys Prognostic Index groups and according to tumor size and HER2. The correlation between SUVmax and Ki-67 was significant. However, the correlation between tumor background count density ratio and Ki-67 was not statistically significant.

CONCLUSION

In DCIS and DCIS-Mi cases, significant correlations were found between increased FDG uptake and several histological and biological factors for poor prognosis (tumor size, Van Nuys Prognostic Index, and HER2).

Two cases of occult breast cancer in which PET-CT was helpful in identifying primary tumors

We report two cases of occult breast cancer in which masses were completely nonpalpable and positron emission tomography-computed tomography (PET-CT) was extremely helpful in identifying the primary tumor. Case 1 involved a 56-year-old woman with enlarged lymph nodes 3 cm in size in the axilla. Based on excisional biopsy, axillary lymph node metastasis of breast cancer was suspected but an obvious primary tumor in the breast was not identifiable on mammography, contrast-enhanced CT, or ultrasonography. Faint accumulation of fluorodeoxyglucose (FDG) was noted only on PET-CT, so the site was considered to be the primary site, and operation was performed. As a result of postoperative pathological examination, ductal carcinoma in-situ (DCIS) was diagnosed. Case 2 involved a 55-year-old woman with enlarged lymph nodes 3 cm in size in the axilla. Based on the excisional biopsy, axillary lymph node metastasis of breast cancer was suspected. In this case as well, an obvious primary tumor was not identifiable with palpation or mammography. On PET-CT, faint accumulation of FDG was noted in the vicinity of the CD regions, or upper and lower outer quadrants. When contrast-enhanced CT and ultrasonography were performed, a faint nodular opacity less than 1 cm in size corresponding to this site was found and diagnosed as the primary site, operation was subsequently performed. Pathologic diagnosis indicated invasive cancer. PET-CT is a helpful option for the diagnosis of occult breast cancer with primary sites that conventional imaging studies have difficulty identifying.

[Upper limb lymphedema revealing breast cancer]

INTRODUCTION

Upper limb lymphedema occurs in 15 to 20% of patients after breast cancer treatment. Upper limb lymphedema without any history of neoplasia is an unusual situation. In this situation, breast cancer should be suspected.

EXEGESIS

We reported two women, 53 and 67 years old, who developed upper limb lymphedema, 18 and 8 months before the diagnosis of breast cancer. In the two cases, clinical examination (breast and axillary palpation) was normal. In one case, mammography led to the diagnosis and in the other breast MRI was required to confirm the cancer.

DISCUSSION

Upper limb lymphedema may be the presenting clinical feature of breast cancer. Breast cancer should be actively sought despite normal clinical and radiological findings. Breast MRI is required in this situation.