Tumoral pseudogout of the proximal interphalangeal joint of a finger: a case report and literature review

Pseudogout growing from the temporomandibular joint into the middle cranial fossa

Calcium pyrophosphate dihydrate deposition disease (CPDD or pseudogout) is a degenerative joint disease. It is defined by the presence of calcium pyrophosphate dihydrate crystals. It usually manifests in the knee and wrist. Manifestation in the temporomandibular joint (TMJ) is only reported in case reports. We present a patient with CPDD mimicking a malignant tumor of the TMJ. A 53-year-old woman presented with progressive pain and a slow-growing swelling of the left TMJ. Imaging showed an extensive mass in the infratemporal fossa extending into the middle cranial fossa and compressing the temporal lobe. Assuming a potential malignancy, we excised the growth, which extended into the dura. We covered the resulting tissue defect within the primary surgery using a microsurgically anastomosed scapular flap and performed further reconstructive surgeries. Calcium pyrophosphate dihydrate crystals were found in the histopathologic examination of the excised tissue, resulting in the diagnosis of CPDD. That is a benign diagnosis, but we treated it like a malignancy. This leads us to the question, was there overtreatment? Tumoral CPDD in the TMJ can be a difficult diagnosis to obtain. The treatment remains controversial, but complete excision of the mass was performed in most reported cases.

An Unusual Pathologic Ulna Fracture Induced by Intraosseous Tumoral Calcium Pyrophosphate Dihydrate Crystal Deposition Disease

In this case report, we describe a novel occurrence of tumoral calcium pyrophosphate dihydrate crystal deposition disease (TCPPDCD) in a 76-year-old man that presented as an unusual, intraosseous, metadiaphyseal lesion of a long bone causing a pathologic fracture. A routine intralesional biopsy was performed, demonstrating granular deposits composed of polarizing, overlapping rhomboid crystals consistent with TCPPDCD. With limited numbers of reported cases of TCPPDCD, and the atypical intraosseous origin seen in this case, it is paramount to thoroughly evaluate all cases of TCPPDCD to clearly differentiate key findings that are essential in diagnosing and managing TCPPDCD.

An Unusual Case of Huge Tophaceous Pseudogout Mimicking as a Tumor-Like Lesion around the Ankle Joint: A Case Report and Literature Review

Pseudogout or calcium pyrophosphate dihydrate deposition disease (CPPD) primarily affects the joints and the periarticular tissues. Tophaceous or tumoral pseudogout is a rare form of this disease which is seen around the joints of extremities. It can be misdiagnosed as a neoplastic condition because of its clinicoradiological similarities, and thus, a proper histopathological examination is indispensable. We report one such case of extra-articular deposition of the CPPD crystals in a 65-year-old man who presented with an asymptomatic swelling around the left ankle. Radiographs showed a dense homogenous calcification, and FNAC revealed dense calcium deposits with numerous rhomboid-shaped crystals. It was managed by en bloc excision, and postoperative biopsy reports confirmed the diagnosis. Possibility of pseudogout should be kept as a differential diagnosis in patients presenting with calcified soft tissue swellings and should be subjected to a detailed histopathological examination for confirmation.