While typically low-risk, cutaneous squamous cell carcinoma (cSCC) can infrequently progress to metastatic disease with in-transit lesions, localized to the dermis or subcutaneous tissue between the primary tumor and draining regional lymph nodes. These lesions are associated with poor prognostic values, including decreased survival rates and increased risk of recurrence. We present the case of a 75-year-old male with cSCC and in-transit metastases on his scalp treated with the immune checkpoint inhibitor (ICI) pembrolizumab in conjunction with diphencyprone (DPCP), a topical hapten that induces a delayed-type hypersensitivity reaction in the skin. The patient was enrolled in a clinical trial (NCT05481658) that involved the twice-weekly application of DPCP 0.04% ointment to four of the in-transit metastases on his frontal scalp, concurrent with pembrolizumab 300 mg administered every three weeks. Following effective sensitization and a twelve-week treatment course, complete clearance of all lesions, DPCP-treated and non-DPCP treated, was achieved, with no adverse events. The immunologic profiles of the post-treatment biopsies were analyzed by TaqMan Low Density Array quantitative real-time polymerase chain reaction to measure immune marker gene expression. Relative to the non-DPCP-treated lesion, the DPCP-treated lesion demonstrated increased pro-inflammatory genetic markers and T-cell activation. This case represents the first reported instance of in-transit metastases of cSCC successfully treated with DPCP and an ICI. It highlights the potential safety and efficacy of DPCP with systemic immunotherapy for the management of in-transit metastases of cSCC in patients for whom surgery and radiation may be contraindicated.

Parotid oncocytoma is a rare salivary gland tumour. Management does not require surgical intervention if diagnosed on a preoperative biopsy. A 64-year-old man presented with a parotid mass diagnosed as mcSCC on fine-needle aspiration cytology (FNAC). Surgical histopathology following parotidectomy demonstrated an oncocytoma of the parotid gland. Parotid oncocytomas are rare; therefore, diagnosis can be difficult. An MRI, CT, and US-guided biopsy are required for diagnosis. Ultrasound-guided core biopsy (UGSB) is more sensitive and specific when compared to FNAC for diagnosing malignant tumours. Diagnoses of benign salivary gland tumours on biopsy remain challenging. The aim of this article is to highlight the difficulty of diagnosing salivary gland tumours. We further aim to outline the contributing features that lead to this misdiagnosis and suggest steps to circumvent it in the future. This report describes the challenges in diagnosing salivary gland tumours and outlines the contributing features of this misdiagnosis. We add to the literature an additional case of a parotid oncocytoma.

UNASSIGNED: Primary and metastatic carcinoma of the small intestine are rare. While most of these malignancies are adenocarcinomas, squamous cell carcinoma (SCC) of the gastrointestinal tract is uncommon. We present a case report of a rare occurrence of skin SCC metastasizing to the ileum, highlighting diagnostic challenges and clinical implications.
METHODS: An 83-year-old female had a history of cutaneous SCC excision in the right temporal region two years prior to the current emergency department visit, followed by metastatic recurrence in a right intra-parotid lymph node treated with radiotherapy. The patient exhibited septic shock and an acute abdomen, and an abdominal computed tomography scan revealed signs of intestinal perforation. Emergency exploratory laparotomy confirmed purulent peritonitis and perforation of the terminal ileum. Subsequently, a 20 cm intestinal resection was performed. Histopathological examination of the resected specimen revealed a 4 cm perforated SCC of the small intestine (pT4 pN0 L0 V1 Pn0 R0).
UNASSIGNED: Metastases of the small intestine are rare. The primary sites for these metastases are typically the uterus, cervix, colon, lung, breast, or melanoma. SCC of the small intestine is particularly rare and poses challenges in diagnosis owing to non-specific symptoms. The prognosis for SCC of the small intestine is generally poor, and the potentially aggressive behavior of some skin SCC emphasizes the need for increased awareness and vigilance in managing such cases.
CONCLUSIONS: This case report underscores the importance of considering metastatic disease in the small bowel of patients with a history of skin SCC who present with new-onset abdominal symptoms.

This report describes a case involving the diagnosis and treatment of squamous cell carcinoma (SCC) of the duodenum, which was found to be a metastatic lesion originating from recurrent head and neck cancer (HNC) in a 74-year-old female patient. The patient had a past medical history of gastroesophageal reflux disease (GERD), tonsillar SCC, and recurrent HNC. She presented with symptoms of burning, tingling, and numbness of the throat and left side of the tongue. Upon examination with an esophagogastroduodenoscopy, an ulcerated hard area mass was detected in the third portion of the duodenum. Biopsy results confirmed the mass to be a metastatic poorly differentiated SCC. The incidence of head and neck squamous cell carcinoma (HNSCC) metastasis to the duodenum is rare, likely due to the unique anatomic location and the lack of lymphatic drainage in the area. The patient was treated with a combination of paclitaxel, carboplatin, and pembrolizumab. This case underscores the significance of considering unusual sites of metastasis in HNSCC patients and utilizing advanced imaging modalities and immunotherapy to detect and treat these locations effectively.

This study reports two cases of squamous cell carcinoma of the thyroid (SCCT) presenting as the thyroid goiter, involving one case of primary squamous cell carcinoma originating from the thyroid (PSCCT) and the other case of secondary SCCT of the thyroid. A retrospective analysis of the clinical and pathological findings was done in this study report. In case 1, the thyroid ultrasound showed multi-hypoechoic well-defined nodules, labeled as 3 using Thyroid Imaging Reporting and Data System, measuring 34.1 mm × 28.9 mm × 30.3 mm and 26.5 mm × 22.2 mm × 23.9 mm in the left in the right lobar thyroid, respectively. The patient underwent surgery and was histologically diagnosed with PSCCT. In case 2, the thyroid ultrasound showed a 25.2 mm × 22.2 mm × 18.8 mm hypoechoic nodule in the right lobar thyroid. The patient underwent a frozen biopsy, the results of which increased suspicion of squamous cell carcinoma. A frozen biopsy was followed by an endoscopic evaluation that detected an ulcerative mass measuring 3.0 cm within the mucosa of esophagus. Due to a scarcity of cases, SCCT is a great challenge for the pathologists and the managing team to come up with the best treatment strategy for the patients.

Here, we discuss the case of a 72-year-old male with a known history of COPD who presented with one month of binocular diplopia and headache. The initial clinical investigation discovered destructive intraosseous lesions within the sellar and para-sellar (SPS) regions, suggesting primary versus metastatic intracranial lesions. Further examination revealed a mass in the right lung, with subsequent biopsy confirming squamous cell carcinoma (SCC) of the lung as the primary site of malignancy. The SPS regions of the basicranium, while well-documented to be associated with various primary neoplasms, rarely serve as sites of metastasis. Throughout this article, we will review the pathophysiology of squamous cell lung cancer, current understandings of SPS metastasis, and considerations of metastatic lung SCC management.

UNASSIGNED: Advanced nonmelanoma skin cancer (NMSC) is a sometimes unrecognized public health burden. The development of immune checkpoint inhibitors (ICIs), such as those affecting programmed cell death protein-1 (PD-1), have dramatically changed the management of advanced NMSC. Dermatologists need to be knowledgeable about these therapies given their key role in diagnosing, treating, and comanaging NMSC. The purpose of this study was to assess the knowledge base and identify knowledge gaps that dermatologists may have regarding ICIs and assess advanced NMSC referral patterns.
UNASSIGNED: A 10-question survey was emailed to United States-based dermatologists in July 2021 assessing knowledge of ICI therapy and referral patterns for metastatic cutaneous squamous cell carcinoma (mcSCC) or locally advanced basal cell carcinoma (laBCC) management.
UNASSIGNED: At their current knowledge level, respondents averaged 40.6 out of 100 (95% CI [35.1, 46.0]) when asked how comfortable they feel counseling a patient on the risks and benefits of an ICI. Seventy-one percent reported that having more information about treatment for mcSCC or laBCC would be helpful in their practice. Being in practice for less than 10 years was not significantly associated with desiring more information about treatment. The respondents reported that the highest number of annual average referrals out for mcSCC or laBCC were made to Mohs surgeons. Fifty-four percent of respondents received referrals for mcSCC or laBCC, and of the providers receiving referrals, 40 percent of them came from general dermatology.
UNASSIGNED: These results demonstrate that a knowledge gap exists for dermatologists in treating mcSCC and laBCC with immunotherapy. There is a need among all dermatologists, regardless of years in practice, to receive this information.

We aimed to analyze risk factors associated with poor survival outcomes for metastatic cutaneous head-and-neck SCC to the parotid.
All patients undergoing surgery for metastatic cutaneous SCC to the parotid with curative intent between 2011 and 2018, were reviewed. Demographic and clinical characteristics were evaluated. Histopathological data including tumor size and histology, tumor grade, TNM stage, resection margins, lymphovascular invasion, and perineural invasion, were analyzed. Overall survival (OS), disease-specific survival (DSS), and freedom from locoregional recurrence (LRR) were assessed.
Ninety patients were included (mean age, 77 years; 75 men [83.3%]). A total parotidectomy was performed in 48 patients (53.3%), and 42 (46.7%) underwent a superficial parotidectomy. Seventy patients (77.8%) underwent adjuvant RT. The median follow-up was 31 months (20-39 months). Tumor volume ≥ 50 cm3 and a shorter RT duration (<20 days) were associated with reduced OS (p = 0.002 and p = 0.01, p = 0.02 and p = 0.009, respectively), and DSS (p = 0.004 and p = 0.02, p = 0.04 and p = 0.02, respectively) on univariable and multivariable analysis, respectively. Only a shorter RT duration was associated with worse freedom from LRR on univariable and multivariable analysis, (p = 0.04 and p < 0.001, respectively). However, with death as a competing risk, a shorter duration of RT was not significantly associated with freedom from LRR.
A shorter duration of adjuvant RT, and excised tumor volume ≥50 cm3 were predictive factors of reduced OS and DSS, and a shorter duration of RT was also associated with reduced freedom from LRR in patients with metastatic SCC to the parotid gland.
4 Laryngoscope, 133:1163-1168, 2023.

Management of advanced cSCC is challenging, and many available systemic medications have modest efficacy. Cemiplimab has demonstrated efficacy in the treatment of advanced cSCC in clinical trials, but real-world data are still limited. With the objective of evaluating the efficacy of cemiplimab in a real-world clinical setting, we conducted a prospective observational study of 13 patients with advanced cSCC. Six patients (46%) had locally advanced disease, while 7 (54%) had metastatic disease. A total of 8 patients (62%) responded to cemiplimab. Five (38%) showed a partial response, while 3 (23%) showed a complete response. Four patients with an initial partial response presented subsequent disease progression during follow-up. Six patients (46%) developed AEs, most of which were mild (G1). PFS was 5.9 months, with a median follow-up was 9 months. In conclusion, cemiplimab demonstrated its utility in the treatment of advanced cSCC, with acceptable response rates, a remarkable number of complete responses, and a very good safety profile.

Management of advanced cSCC is challenging, and many available systemic medications have modest efficacy. Cemiplimab has demonstrated efficacy in the treatment of advanced cSCC in clinical trials, but real-world data are still limited. With the objective of evaluating the efficacy of cemiplimab in a real-world clinical setting, we conducted a prospective observational study of 13 patients with advanced cSCC. Six patients (46%) had locally advanced disease, while 7 (54%) had metastatic disease. A total of 8 patients (62%) responded to cemiplimab. Five (38%) showed a partial response, while 3 (23%) showed a complete response. Four patients with an initial partial response presented subsequent disease progression during follow-up. Six patients (46%) developed AEs, most of which were mild (G1). PFS was 5.9 months, with a median follow-up was 9 months. In conclusion, cemiplimab demonstrated its utility in the treatment of advanced cSCC, with acceptable response rates, a remarkable number of complete responses, and a very good safety profile.