Tubarial salivary glands on PSMA ligands based PET imaging and post 177Lu PSMA therapy scan: reiterating its importance.

68Ga-PSMA PET/CT has been routinely utilized in patients with intermediate to high-risk category prostate carcinoma for staging, biochemical recurrence and before planning the PSMA radioligand therapy (RLT). 177Lu-PSMA RLT has also been approved by FDA as a novel treatment modality in metastatic carcinoma prostate patients who have failed to other lines of treatment. The non-target organs like salivary and lacrimal glands have shown to have high physiological PSMA uptake on PSMA PET/CT. Recently, strong uptake of PSMA ligand has also been noted in the dorsal wall of the nasopharynx in the region of torus tubarius on PSMA PET/CT, which has led to the identification of new pair of salivary gland structures called "tubarial salivary glands". The clinical significance of these distinct anatomical structures lies in the fact these structures might be involved in a variety of immune related, inflammatory disorders, malignancies and could be a probable organ at risk during radiotherapy in case of head and neck malignancies, causing adverse effects to the patient.

Tibial Stress Fracture and "Shin Splint" Syndrome in the Same Patient Diagnosed on 99mTC-Methylene Diphosphonate Bone Scintigraphy and Single-Photon Emission/Computed Tomography.

We present a case of an 18-year-old male athlete who presented with complaints of right lower leg pain for 10 days following intense exercise. The most likely diagnosis was a possible tibial stress fracture or a ''shin splint'' syndrome. The radiograph did not reveal any significant abnormality in the form of any fracture or a cortical break. We performed planar bone scintigraphy including single-photon emission computed tomography (CT)/CT that revealed the presence of the two concomitant pathologies in the form of a hot spot which corresponded with a bone lesion in the tibial stress fracture and subtle remodeling activity without evidence of significant cortical lesion in the shin splints in bilateral lower limbs (R>L).

A Case of Extracranial Metastasis of Glioblastoma Multiforme Seen on Bone Scintigraphy.

Glioblastoma multiforme (GBM) is the most common primary malignant tumor of the central nervous system in adults. It is known for its devastating intracranial progress thus attributing to its very short survival. Here, we report a case of 37-year-old female with GBM post surgery, chemotherapy and radiotherapy who presented with pain in right hip region. She was referred to our department for evaluation of skeletal metastasis. Tc-99m methylene diphosphonate bone scan revealed an expansile lesion involving the right iliac blade along with extensive lytic bony lesions throughout the axial skeleton.

Unexpected Metastasis to Breast, Lymph Node, Subcutaneous, Abdominal Wall, Intraabdominal, and Bone in Osteogenic Osteosarcoma: An Unusual Presentation on Bone Scintigraphy.

Osteogenic osteosarcoma is an aggressive malignant bone tumor with the tendency for local invasion and early metastases. Radionuclide bone scans play an important role in disease management by identifying other areas of skeletal involvement as well as extraosseous metastases. Osteogenic sarcoma metastasis is known to accumulate bone-avid agents due to their osteogenic potential. Here, we report a case of osteogenic osteosarcoma of distal femur with the absence of pleural effusion but extensive extraosseous areas of metastatic involvement in distant lymph nodes, subcutaneous planes (in the form of nodules), abdominal wall, multiple intraperitoneal deposits, breast, and bone metastases visualized on preoperative Tc-99 m methylene diphosphonate bone scan.

Role of 99mTc-Methylene Diphosphonate Bone Scintigraphy in the Evaluation of the Viability and the Incorporation of the Bone Allograft Used in Orthopedic Reconstruction.

Allogenic bone is the most commonly grafted tissue which provides only osteoconductive property, in which it acts as a scaffold to facilitate the ingrowth of the vessels and migration of host cells capable of osteogenesis. It can be used as a substitute for autografts as the latter is associated with morbidity and limited donor site availability. Its applications are expanding in all aspects of orthopedic surgery, notably in revision hip replacement or surgical treatment for bone tumors or benign conditions. The balance between osteolysis and osteogenesis must be maintained for graft incorporation to occur and thus postoperative imaging is essential for differentiation between grafts and recurrent disease or viability/nonviability. Here, we present three cases, in which bone allografting was done who underwent serial 99 mTc-methylene diphosphonate three-phase bone scintigraphy with single-photon emission computed tomography/computed tomography to assess the viability, integrity, and the incorporation of the graft.