Bone metastasis pattern of cancer patients with bone metastasis but no visceral metastasis

Abstract

BackgroundBone metastasis of cancer can be a result from systemic blood spreading or vertebral venous plexus spreading. Systemic blood pathway induced bone metastasis can happen in any bone in the body since the spreading is considered to be random. However, it remains unknown whether there is any pattern of vertebral venous plexus related bone metastasis. In this study, we explored bone metastasis patterns in patients whose primary tumors had been well identified.MethodsWe included 290 consecutive cancer patients with bone metastases but no visceral metastases, out of 2559 patients whose bone metastases were diagnosed by positron emission tomography/computed tomography, between Jan 2015 and Oct 2017 at the Fudan University Shanghai Cancer Center. We excluded those with visceral metastasis to ensure that our study focused on metastasis through the vertebral venous plexus. And we analyzed the distribution and pattern of skeletal metastases.ResultsOf the 290 patients, 28 had head and neck tumors, 178 had thorax tumors, 49 had abdominal tumors and 35 had pelvic tumors; 102 (35%) had only one bone containing a metastasis and 188 (65%) had multiple bones containing metastases. Overall, metastases to the thoracic skeleton were more common in patients with thorax tumors than in other patients (81% vs. 67%, P = 0.007); metastases to the cervical spine or thoracic bones were more common in patients with primary tumors above the diaphragm than those below the diaphragm (82% vs. 66%, P = 0.002). Among those with only one bone containing a metastasis (n = 102), patients with head and neck tumors had a higher incidence of cervical spine metastasis than other patients (25% vs. 2%, P = 0.03), those with thorax tumors had a higher incidence of thoracic bone metastasis than other patients (56% vs. 35%, P = 0.035), and those with pelvic tumors had a higher incidence of pelvis bone metastasis than other patients (78% vs. 27%, P = 0.000054).ConclusionsIn patients with only one bone containing a metastasis but no visceral metastasis, bones near the primary were more likely to be first metastasized. This may be a valuable clue to primary tumor sites in patients with cancers of unknown primaries.

Sentinel node theory helps tracking of primary lesions of cancers of unknown primary

“…It would be very helpful and convenient if we could determine the clinical clues that could guide the search of the primary sites of CUP patients. Our team has reported that oligo bone metastasis may suggest the primary site to be in the neighboring area in patients without visceral metastasis [12]. Lymphatic spreading is a relatively early process in distant metastasis of cancer and nodal metastasis of most primary-known solid tumors follows sentinel lymph node (SLN) theory.…”

Cancer of Unknown Primary Presenting as Bone-Predominant or Lymph Node-Only Disease: A Clinicopathologic Portrait

“…These uncommon sites for CUP presentation without visceral disease herald a unique subtype within the heterogeneous CUP entity and drive unique approaches in terms of their risk stratification and treatment. As both lymph node and bony metastases can develop far from a primary cancer, the location may not reliably provide an anatomic correlation in the search for the potential primary site and wide differential for putative primary cancers exists [3]. The workup of BCUP additionally poses unique challenges related to limited tissue availability and imaging sensitivity.…”

Sentinel node theory helps tracking of primary lesions of cancers of unknown primary

“…It would be very helpful and convenient if we could determine the clinical clues that could guide the search of the primary sites of CUP patients. Our team has reported that oligo bone metastasis may suggest the primary site to be in the neighboring area in patients without visceral metastasis 12 .…”