Indian Journal of Nuclear Medicine

LETTER TO EDITOR
Year
: 2012  |  Volume : 27  |  Issue : 2  |  Page : 133--134

Incidental detection of axillary lymph node metastasis from carcinoma breast during technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy


Sasikumar Arun, Ashwani Sood, Anish Bhattacharya, Bhagwant Rai Mittal 
 Department of Nuclear Medicine and PET, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Correspondence Address:
Bhagwant Rai Mittal
Department of Nuclear Medicine and PET, PGIMER, Chandigarh - 160 012
India




How to cite this article:
Arun S, Sood A, Bhattacharya A, Mittal BR. Incidental detection of axillary lymph node metastasis from carcinoma breast during technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy.Indian J Nucl Med 2012;27:133-134


How to cite this URL:
Arun S, Sood A, Bhattacharya A, Mittal BR. Incidental detection of axillary lymph node metastasis from carcinoma breast during technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy. Indian J Nucl Med [serial online] 2012 [cited 2020 Feb 20 ];27:133-134
Available from: http://www.ijnm.in/text.asp?2012/27/2/133/110706


Full Text

Sir,

We describe a suspected case of primary hyperparathyroidism with brown tumors where on parathyroid scintigraphy, an incidental finding of hyper-metabolic lesion in the right axilla, was noticed which was later on confirmed to be metastasis from breast cancer. A 61-year-old-female patient presented with back pain for 6 months duration. She had hypercalcemia and elevated serum alkaline phosphatase levels. X-ray of the skull and pelvis showed multiple lytic lesions which raised the suspicion of primary hyperparathyroidism with brown tumors. Technetium- 99m methoxyisobutylisonitrile (MIBI) parathyroid scintigraphy [Figure 1]a and b was negative for parathyroid adenoma; however, a hypermetabolic lesion in right axilla was noted. Single photon emission computed tomography/computed tomography (SPECT/CT) localized the uptake to the right axillary lymph node (arrows on CT and SPECT/CT images). It also showed multiple lytic lesions in cervico-dorsal vertebrae. Scintigraphic impression of metastatic right axillary nodal involvement was made. Keeping the probability of primary malignancy in breast, she was further subjected to mammography which on Breast Imaging-Reporting and Data System (BIRADS) showed BIRADS 5 on right side and BIRADS 2 on left side. Ultrasound of the breast revealed a heterogenous hyperechoic lesion of size 9 mm × 5 mm which was not palpable on clinical examination. Ultrasound guided fine needle aspiration cytology reported lesion in right breast as carcinoma infiltrating duct and from right axillary lymph nodes as metastasis. Whole body bone scan with technetium-99m methylene diphosphonate (MDP) revealed increased osteoblastic activity in multiple bones suggestive of wide spread skeletal metastasis [Figure 1]e and f.{Figure 1}

The uptake mechanism of Tc99m-MIBI involves passive diffusion across plasma and mitochondrial membranes and at equilibrium it is sequestered within mitochondria by the large negative transmembrane potentials. [1] Studies have confirmed the relationship between cellular uptake of MIBI and mitochondrial activity or density. [2] The multi-drug-resistant P-glycoprotein system uses MIBI as a substrate and effectively transports it out of tumor cell. [3] The overall concentration of Tc99m MIBI in tumors is a function of many variables including factors that affect the rate of uptake and that determine wash out or excretion from the cell. [4] Tc99m-MIBI uptake in axillary lymph nodes could be due to involvement of lymphoma, [5] metastases of breast malignancy, [6] and extravasated radioactivity in the ipsilateral upper limb. [7] There have been studies evaluating the role of scintimammography using Tc99m MIBI for evaluation of primary carcinoma of breast and axillary lymph node metastasis. [8],[9] Hypermetabolic lesion in axilla as an incidental finding in planar parathyroid scintigraphy with localization to lymph nodes on SPECT/CT in this suspected case of primary hyperparathyroidism with brown tumors has helped in further evaluation for breast cancer. Subsequently, it was confirmed to be a case of breast carcinoma with axillary lymph nodal and bone metastases with hypercalcemia of malignancy. The findings had essentially changed the diagnosis and hence the management of the patient.

References

1Piwnica-Worms D, Kronauge JF, Chiu ML. Uptake and retention of hexakis (2-methoxyisobutyl isonitrile) technetium (I) in cultured chick myocardial cells. Mitochondrial and plasma membrane potential dependence. Circulation 1990;82:1826-38.
2Delmon-Moingeon LI, Piwnica-Worms D, Van den Abbeele AD, Holman BL, Davison A, Jones AG. Uptake of the cation hexakis (2-methoxyisobutylisonitrile)-technetium-99m by human carcinoma cell lines in vitro. Cancer Res 1990;50:2198-202.
3Piwnica-Worms D, Holman BL. Noncardiac applications of hexakis (alkylisonitrile) technetium-99m complexes. J Nucl Med 1990;31:1166-7.
4Waxman AD. The role of (99m) Tc methoxyisobutylisonitrile in imaging breast cancer. Semin Nucl Med 1997;27:40-54.
5Williams KA, Hill KA, Sheridan CM. Noncardiac findings on dual-isotope myocardial perfusion SPECT. J Nucl Cardiol 2003;10:395-402.
6Taillefer R, Robidoux A, Turpin S, Lambert R, Cantin J, Léveillé J. Metastatic axillary lymph node technetium-99m-MIBI imaging in primary breast cancer. J Nucl Med 1998;39:459-64.
7Shih WJ, Han JK, Coupal J, Wierzbinski B, Magoun S, Gross K. Axillary lymph node uptake of Tc-99m MIBI resulting from extravasation should not be misinterpreted as metastasis. Ann Nucl Med 1999;13:269-71.
8Khalkhali I, Cutrone J, Mena I, Diggles L, Venegas R, Vargas H, et al. Technetium-99m-sestamibi scintimammography of breast lesions: Clinical and pathological follow-up. J Nucl Med 1995;36:1784-9.
9Palmedo H, Schomburg A, Grünwald F, Mallmann P, Krebs D, Biersack HJ. Technetium-99m-MIBI scintimammography for suspicious breast lesions. J Nucl Med 1996;37:626-30.