Intraparotid Recurrence of Papillary Thyroid Carcinoma After Thyroidectomy Coincident With Declining Thyroglobulin Levels: A Case Report and Review of the Literature.

Papillary thyroid carcinoma (PTC) is the most frequent thyroid malignancy. Intraparotid recurrence of PTC is, however, rare. Most parotid malignancies are either primary or metastatic from cancer outside the head and neck. We report a case of a 71-year-old man who had undergone lobectomy and completion thyroidectomy for PTC and presented to our clinic with an insidious intraparotid recurrence, for which he underwent a superficial parotidectomy and radioactive iodine therapy. We also present a review of the literature on similar cases. Intraparotid metastasis of PTC should be considered in the differential diagnosis of a parotid mass.

Thyroid neoplasm in Makkah region, Saudi Arabia. A retrospective epidemiological study.

OBJECTIVES: To improve our local data and demographics of thyroid neoplasm in Makkah region, Kingdom of Saudi Arabia and provide some basic statistics for future studies in our local community.  Methods: A record based retrospective epidemiological study was conducted and included 314 thyroid disease patients who were presented to our centers at Makkah region, Kingdom of Saudi Arabia between December 2009 and December 2019. Results: A descriptive statistical analysis was carried out. The average age was 42.77 years, with a female-to-male ratio of 3:1, and most of the patients were Saudi (77%). Fifty-seven percent of cases were benign, while in malignant cases, 33.4% were papillary thyroid carcinoma. The mean follow-up time was 15.44 months, with excellent compliance in 39.4% of the patients.   Conclusion: Thyroid tumors have a leading incidence in head and neck tumors in Makkah, Kingdom of Saudi Arabia, mandating further studies to determine the causes and distribution in other regions of the country.

Role of fine-needle aspiration cytology in evaluating thyroid nodules. A retrospective study from a tertiary care center of Western region, Saudi Arabia.

OBJECTIVES: To evaluate the accuracy and e cacy of ne-needle aspiration cytology (FNAC) in diagnosing thyroid nodules, correlating it with the histopathological findings. METHODS: A retrospective evaluation of 314 patients was undertaken at a tertiary referral center of King Abdullah Medical City (KAMC), Makkah, Kingdom of Saudi Arabia, between 2010-2019. Patients who presented with thyroid swellings underwent ultrasonography and FNAC. If indicated, surgery was performed. The FNAC findings were compared to the final histopathological reports. RESULTS: The findings for FNAC from our data set of 314 patients showed a sensitivity value of 79.8%, specificity of 82.1%, accuracy of 74.8%, positive predictive value of 74.8%, and negative predictive value of 85.9%. Conclusion: Our study showed that FNAC has high sensitivity and speci city in the initial evaluation of patients with thyroid nodules. When guided by ultrasonography, the accuracy can be markedly improved. Molecular markers once widely available can improve the diagnostic power of FNAC to be no less than the histopathologic evaluation of thyroid tissue.

Thyroglossal duct surgery. What is the acceptable recurrence rate?

OBJECTIVES: To present experiences of different specialties in the treatment of thyroglossal duct cysts (TGDCs) and subsequent complications in multiple centers.  Methods: A retrospective cross-sectional study of all cases of TGDC for a period of 11 years from 2008-2019 by different departments from 3 different centers in Jeddah, Kingdom of Saudi Arabia (King Faisal Specialist Hospital and Research Centre, Bakhsh Hospital and International Medical Center). Results: Forty-nine patients were included. The type of surgery performed plays a significant role in recurrence (p less than 0.001). The Sistrunk procedure had a lower recurrence rate (0%) than simple excision (70%) and has showed a significantly long recurrence-free interval (p less than 0.001). Higher recurrence rates are associated with higher postoperative complications (p=0.002). Patients who underwent pre-operative fine needle aspiration did not have any recurrence during the follow-up period. Conclusion: The Sistrunk procedure is the gold standard technique with the highest recurrence-free interval rate. Fine needle aspiration could be recommended as a less invasive procedure to exclude malignancy.

Primary cutaneous vs. parotid mucoepidermoid carcinoma of the scalp: A case report.

Primary cutaneous mucoepidermoid carcinoma remains a rare occurrence. This is the first report of a case of primary cutaneous mucoepidermoid carcinoma originating on the scalp and subsequently metastasizing to the parotid gland. The patient was a 53-year-old female who presented with a purple mass on her scalp since 5 months prior to examination. Histopathology revealed nests and islands of atypical epithelioid cells with pleomorphism, medium to prominent nucleoli, and scattered mucin deposition highlighting with a mucicarmine stain. The atypical cells demonstrated intravascular involvement. These findings were compatible with metastatic adenocarcinoma. Later, fine needle aspiration of the patient's parotid lesion revealed malignant cells from a poorly differentiated carcinoma that appeared similar to the patient's previously excised scalp lesion. In addition to summarizing this patient's presentation, clinical course, and management, we discuss the diagnostic challenges posed by this atypical presentation. Primary cutaneous mucoepidermoid carcinoma should be considered in the differential diagnosis of patients presenting with a scalp mass. Moreover, patients with primary cutaneous mucoepidermoid carcinoma originating on the scalp should be evaluated for possible metastases.

Characterization of neuronal cell death in the spiral ganglia of a mouse model of endolymphatic hydrops.

HYPOTHESIS: Spiral ganglion neurons (SGN) in the Phex male mouse, a murine model of postnatal endolymphatic hydrops (ELH) undergo progressive deterioration reminiscent of human and other animal models of ELH with features suggesting apoptosis as an important mechanism. BACKGROUND: Histologic analysis of the mutant's cochlea demonstrates ELH by postnatal Day (P) 21 and SGN loss by P90. The SGN loss seems to occur in a consistent topographic pattern beginning at the cochlear apex. METHODS: SGN were counted at P60, P90, and P120. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative PCR, and immunohistochemical analyses of activated caspase-3, caspase-8, and caspase-9 were performed on cochlear sections obtained from mutants and controls. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling assay (TUNEL) was carried out on 2 mutants and 2 controls. RESULTS: Corrected SGN counts in control mice were greater in the apical turn of the cochleae at P90 and P120, respectively (p < 0.01). Increased expression of activated caspase-3, caspase-8, and caspase-9 was seen in the mutant. At later time points, activated caspase expression gradually declined in the apical turns and increased in basal turns of the cochlea. Quantitative and semiquantitative PCR analysis confirmed increased expression of caspase-3, caspase-8, and caspase-9 at P21 and P40. TUNEL staining demonstrated apoptosis at P90 in the apical and basal turns of the mutant cochleae. CONCLUSION: SGN degeneration in the Phex /Y mouse seems to mimic patterns observed in other animals with ELH. Apoptosis plays an important role in the degeneration of the SGN in the Phex male mouse.

Photodynamic therapy of cottontail rabbit papillomavirus-induced papillomas in a severe combined immunodeficient mouse xenograft system.

OBJECTIVES/HYPOTHESIS: To evaluate the efficacy of photodynamic therapy (PDT) with the phthalocyanine photosensitizer Pc 4 for treating an animal model of recurrent respiratory papillomatosis (RRP). METHODS: Rabbit skin was grafted onto the dorsum of severe combined immunodeficient mice, two xenografts per animal. After the graft healed, it was inoculated with cottontail rabbit papillomavirus (CRPV). When papillomas developed, Pc 4 (0.6 or 1.0 mg/kg) was administered systemically, and 48 hours later, one papilloma of the two on each animal was exposed to 675-nm photoactivating light at either 100 or 150 J/cm(2). In addition to the contralateral tumors, which received Pc 4 but no light, other controls included animals receiving light only or neither agent. Response was assessed by measuring papilloma size with a caliper. Some papillomas and residual skin were harvested for histological assessment. RESULTS: For the lower-dose PDT regimens, papilloma growth rates were not significantly different from the controls. In contrast, 13 of 15 papillomas receiving the higher Pc 4 dose (1.0 mg/kg) and the higher light fluence (150 J/cm(2)) regressed completely and did not regrow within the observation period of up to 79 days. The response of these papillomas was significantly different from the controls (P < .001). Histological analysis confirmed the absence of residual tumor following complete response and replacement with near-normal epithelium. CONCLUSIONS: Pc 4-PDT is highly effective in treating virally induced (CRPV) papillomas in a murine model of RRP, and thus warrants further study as a treatment for HPV-induced papillomas.

Promoter, alternative splice forms, and genomic structure of protocadherin 15.

We originally showed that the protocadherin 15 gene (Pcdh15) is necessary for hearing and balance functions; mutations in Pcdh15 affect hair cell development in Ames waltzer (av) mice. Here we extend that study to understand better how Pcdh15 operates in a cell. The original report identified 33 exons in Pcdh15, with exon 1 being noncoding; additional exons of Pcdh15 have since been reported. The 33 exons of Pcdh15 described originally are embedded in 409 kb of mouse genomic sequence, while the corresponding exons of human PCDH15 are spread over 980 kb of genomic DNA; the exons in Pcdh15/PCDH15 range in size from 9 to approximately 2000 bp. The genomic organization of Pcdh15/PCDH15 bears similarity to that of cadherin 23, but differs significantly from other protocadherin genes, such as Pcdhalpha, beta, or gamma. A CpG island is located approximately 2900 bp upstream of the PCDH15 transcriptional start site. The Pcdh15/PCDH15 promoter lacks TATAA or CAAT sequences within 100 bases upstream of the transcription start site; deletion mapping showed that Pcdh15 harbors suppressor and enhancer elements. Preliminary searches for alternatively spliced transcripts of Pcdh15 identified novel splice variants not reported previously. Results from our study show that both mouse and human protocadherin 15 genes have complex genomic structures and transcription control mechanisms.