Detection of primary sites in unknown primary tumors using FDG-PET or FDG-PET/CT

Jong Sun Park, Jae-Joon Yim, Won Jun Kang, June-Key Chung, Chul-Gyu Yoo, Young Whan Kim, Sung Koo Han, Young-Soo Shim, Sang-Min Lee, Jong Sun Park, Jae-Joon Yim, Won Jun Kang, June-Key Chung, Chul-Gyu Yoo, Young Whan Kim, Sung Koo Han, Young-Soo Shim, Sang-Min Lee

Abstract

Background: Carcinoma of unknown primary tumors (CUP) is present in 0.5%-9% of all patients with malignant neoplasms; only 20%-27% of primary sites are identified before the patients die. Currently, 18F-fluorodeoxy-glucose positron-emission tomography (18F-FDG PET) or PET combined with computed tomography (PET/CT) is widely used for the diagnosis of CUP. However, the diagnostic yield of the primary site varies. The aim of this study was to determine whether PET or PET/CT has additional advantages over the conventional diagnostic workup in detecting the primary origin of CUP.

Findings: Twenty patients with unknown primary tumors that underwent PET or PET/CT were included in this study. For all patients, the conventional diagnostic workup was unsuccessful in detecting the primary sites. Among 20 patients, 11 had PET scans. The remaining nine patients had PET/CT. In all 20 patients, neither the PET nor PET/CT identified the primary site of the tumor, including six cases with cervical lymph node metastases. The PET and PET/CT revealed sites of FDG uptake other than those associated with known metastases in seven patients, but these findings did not influence patient management or therapy. Two patients had unnecessary invasive diagnostic procedures due to false positive results on the PET or PET/CT.

Conclusions: Although it is inconclusive because of small sample size of the study, the additional value of PET or PET/CT for the detection of primary sites in patients with CUP might be less than expected; especially in patients that have already had extensive conventional diagnostic workups. Further study is needed to confirm this finding.

Figures

Figure 1
Figure 1
A 54-year-old male with right cervical lymph node metastasis from an unknown primary tumor (patient 9): The patient had radical neck dissection, tonsillectomy, blind biopsy of the nasopharynx and tongue base. The pathology revealed metastatic squamous cell carcinoma in one out of 20 lymph nodes. However, there was no evidence of malignancy in other tissues including tonsiles, tongue base, parotid gland, salivary gland, or nasopharynx; (A) PET/CT showed a hypermetabolic lesion (SUV 13.0) in right cervical lymph node(arrow) at level II; (B) There was no additional FDG uptake suggesting a primary site in the transaxial PET/CT scans of the chest and pelvis.

References

    1. Abbruzzese JL, Abbruzzese MC, Lenzi R, Hess KR, Raber MN. Analysis of a diagnostic strategy for patients with suspected tumors of unknown origin. J Clin Oncol. 1995;13:2094–2103.
    1. Le Chevalier T, Cvitkovic E, Caille P, Harvey J, Contesso G, Spielmann M, Rouesse J. Early metastatic cancer of unknown primary origin at presentation. A clinical study of 302 consecutive autopsied patients. Arch Intern Med. 1988;148:2035–2039. doi: 10.1001/archinte.148.9.2035.
    1. Raber MN, Faintuch J, Abbruzzese JL, Sumrall C, Frost P. Continuous infusion 5-fluorouracil, etoposide and cis-diamminedichloroplatinum in patients with metastatic carcinoma of unknown primary origin. Ann Oncol. 1991;2:519–520.
    1. Haas I, Hoffmann TK, Engers R, Ganzer U. Diagnostic strategies in cervical carcinoma of an unknown primary (CUP) Eur Arch Otorhinolaryngol. 2002;259:325–333. doi: 10.1007/s004050100408.
    1. Kwee TC, Basu S, Cheng G, Alavi A. FDG PET/CT in carcinoma of unknown primary. Eur J Nucl Med Mol Imaging. 2010;37:635–644. doi: 10.1007/s00259-009-1295-6.
    1. Rusthoven KE, Koshy M, Paulino AC. The role of fluorodeoxyglucose positron emission tomography in cervical lymph node metastases from an unknown primary tumor. Cancer. 2004;101:2641–2649. doi: 10.1002/cncr.20687.
    1. Seve P, Billotey C, Broussolle C, Dumontet C, Mackey JR. The role of 2-deoxy-2-[F-18]fluoro-D-glucose positron emission tomography in disseminated carcinoma of unknown primary site. Cancer. 2007;109:292–299. doi: 10.1002/cncr.22410.
    1. Kwee TC, Kwee RM. Combined FDG-PET/CT for the detection of unknown primary tumors: systematic review and meta-analysis. Eur Radiol. 2009;19:731–744. doi: 10.1007/s00330-008-1194-4.
    1. Chang JM, Lee HJ, Goo JM, Lee HY, Lee JJ, Chung JK, Im JG. False positive and false negative FDG-PET scans in various thoracic diseases. Korean J Radiol. 2006;7:57–69. doi: 10.3348/kjr.2006.7.1.57.
    1. Stokkel MP, Terhaard CH, Hordijk GJ, van Rijk PP. The detection of unknown primary tumors in patients with cervical metastases by dual-head positron emission tomography. Oral Oncol. 1999;35:390–394. doi: 10.1016/S1368-8375(98)00129-8.
    1. OS AA, Fischbein NJ, Caputo GR, Kaplan MJ, Price DC, Singer MI, Dillon WP, Hawkins RA. Metastatic head and neck cancer: role and usefulness of FDG PET in locating occult primary tumors. Radiology. 1999;210:177–181.
    1. Regelink G, Brouwer J, de Bree R, Pruim J, van der Laan BF, Vaalburg W, Hoekstra OS, Comans EF, Vissink A, Leemans CR, Roodenburg JL. Detection of unknown primary tumours and distant metastases in patients with cervical metastases: value of FDG-PET versus conventional modalities. Eur J Nucl Med Mol Imaging. 2002;29:1024–1030. doi: 10.1007/s00259-002-0819-0.
    1. Nanni C, Rubello D, Castellucci P, Farsad M, Franchi R, Toso S, Barile C, Rampin L, Nibale O, Fanti S. Role of 18F-FDG PET-CT imaging for the detection of an unknown primary tumour: preliminary results in 21 patients. Eur J Nucl Med Mol Imaging. 2005;32:589–592. doi: 10.1007/s00259-004-1734-3.
    1. Gutzeit A, Antoch G, Kuhl H, Egelhof T, Fischer M, Hauth E, Goehde S, Bockisch A, Debatin J, Freudenberg L. Unknown primary tumors: detection with dual-modality PET/CT--initial experience. Radiology. 2005;234:227–234. doi: 10.1148/radiol.2341031554.
    1. Pelosi E, Pennone M, Deandreis D, Douroukas A, Mancini M, Bisi G. Role of whole body positron emission tomography/computed tomography scan with 18F-fluorodeoxyglucose in patients with biopsy proven tumor metastases from unknown primary site. Q J Nucl Med Mol Imaging. 2006;50:15–22.
    1. Lassen U, Daugaard G, Eigtved A, Damgaard K, Friberg L. 18F-FDG whole body positron emission tomography (PET) in patients with unknown primary tumours (UPT) Eur J Cancer. 1999;35:1076–1082. doi: 10.1016/S0959-8049(99)00077-5.
    1. Bohuslavizki KH, Klutmann S, Kroger S, Sonnemann U, Buchert R, Werner JA, Mester J, Clausen M. FDG PET detection of unknown primary tumors. J Nucl Med. 2000;41:816–822.
    1. Alberini JL, Belhocine T, Hustinx R, Daenen F, Rigo P. Whole-body positron emission tomography using fluorodeoxyglucose in patients with metastases of unknown primary tumours (CUP syndrome) Nucl Med Commun. 2003;24:1081–1086. doi: 10.1097/00006231-200310000-00008.
    1. Juweid ME, Cheson BD. Positron-emission tomography and assessment of cancer therapy. N Engl J Med. 2006;354:496–507. doi: 10.1056/NEJMra050276.
    1. Naresh KN. Do metastatic tumours from an unknown primary reflect angiogenic incompetence of the tumour at the primary site?--a hypothesis. Med Hypotheses. 2002;59:357–360. doi: 10.1016/S0306-9877(02)00221-9.

Source: PubMed

Patrocinadores e Colaboradores

Condições médicas

Intervenções de drogas

3
Se inscrever