F-18 FDG PET/CT Imaging of a Hidradenocarcinoma of Head and Neck

The utility of [¹⁸F] FDG PET/CT in staging hidradenocarcinoma

Hidradenocarcinoma is a rare and aggressive malignant cutaneous adnexal tumor that originates from the intradermal ducts of eccrine sweat glands. Herein, we report a case of hidradenocarcinoma that had transformed from a previously excised benign hidradenoma. [18F] FDG PET/CT revealed an FDG-avid mass in the left calf, and extensive metastatic disease, including soft tissue, pulmonary, osseous, and extensive nodal metastases. This case underscores the potential for malignant transformation of hidradenoma and highlights the utility of [18F] FDG PET/CT in staging hidradenocarcinoma.

Case report: High-grade hidradenocarcinoma of the chest wall with insights from 18F-FDG PET/CT imaging and a review of the literature

Hidradenocarcinoma (HAC) is a rare neoplasm that typically occurs in the head and neck region but seldom affects the chest wall. Histopathology and immunohistochemistry remain essential for diagnosing HAC, although their clinical utility in determining metastasis can be limited. Given the pathological rarity and histopathological heterogeneity of HAC, we report a case demonstrating the utility of positron emission tomography/computed tomography (PET/CT) combined with immunohistochemical examination for the accurate diagnosis and staging of HAC. An 84-year-old woman presented to our hospital with a right chest wall and axillary mass. A pathological examination was performed, which revealed a malignancy of epithelial origin. The immunohistochemical examination confirmed a high-grade hidradenocarcinoma. Subsequently, PET/CT examination showed significant hypermetabolism in the right chest wall and its ipsilateral axillary and subclavian lymph nodes. Combined with pathological findings, these results confirmed metastatic hidradenocarcinoma, leading to a TNM classification of T2N3M (stage IV). A literature review revealed that HAC rarely occurs in the chest wall but tends to metastasize. However, the prognosis is favorable, especially with early diagnosis and surgical intervention. 18F-FDG PET/CT examination is a valuable staging tool in the comprehensive assessment of systemic tumor metastasis. Combining PET/CT with pathological examination enhances diagnostic and staging accuracy, enabling timely treatment and improving outcomes.

Significantly Higher 68 Ga-FAPI Than 18 F-FDG Uptake by Hidradenocarcinoma of Head and Neck on PET/CT

ABSTRACT

Hidradenocarcinoma is quite rare in clinical practice. Herein, we describe the 68 Ga-FAPI and 18 F-FDG PET/CT findings of hidradenocarcinoma of the head and neck in a 75-year-old man. In the present case, the primary tumor and secondary lesions showed intense accumulation of 68 Ga-FAPI but only slight 18 F-FDG uptake. This case demonstrates that 68 Ga-FAPI PET/CT might be used as a helpful tool for evaluating hidradenocarcinoma.

Comparison of 68 Ga-FAPI and 18 F-FDG PET/CT in Finger Hidradenocarcinoma

ABSTRACT

We report a case of hidradenocarcinoma, which showed only slight 18 F-FDG uptake. However, the rare sweat gland tumor demonstrated intense tracer uptake on 68 Ga-FAPI PET/CT. This case demonstrates the potential value of 68 Ga-FAPI PET/CT for the evaluation of hidradenocarcinoma.

Malignant Nodular Hidradenoma of the Left Knee: A Malignant Mystery With an Overview of Literature

Malignant nodular hidradenoma is a rare eccrine sweat gland neoplasm characterized by recurrence, metastasis, and a locally aggressive course. In our case report, a 74-year-old man presented with a seemingly benign swelling which was persistent for the last 30 years, which was excised at an outside institute. Since the patient presented to the hospital during the peak of the pandemic, considering the age of the patient, the pandemic situation, the logistics of radiotherapy during such a situation, preserving the knee joint function in view of close proximity of the tumour to the joint, it was decided to keep the patient on follow up and continue expectant management. After a follow-up period of 24 months, no locoregional recurrence or metastasis has been observed. The patient is on annual follow-up with clinical examination and PET-CECT imaging.

Poroid Hidradenocarcinoma of the Ankle: Case Report of a Rare Malignant Cutaneous Adnexal Neoplasm

Soft-tissue masses on the anterior ankle result from a broad range of underlying processes, often presenting a diagnostic challenge. Appropriate treatment of these tumors can be determined by using a combination of patient history, interpretation of pathologic findings, physical examination, and radiographic appearance. We present a case of an exceptionally rare malignant cutaneous adnexal tumor, highlighting the importance of adherence to fundamental biopsy principles for diagnosing and managing musculoskeletal lesions.

Malignant Transformation of Nodular Hidradenoma in the Lower Leg

Nodular hidradenoma (NH) is a benign adnexal tumor that arises from either eccrine or apocrine sweat glands. NH can originate from any cutaneous site, but the most common sites are the head and anterior surface of the trunk, with very rare cases in the extremities. Long-standing NH has been reported to undergo malignant transformation to malignant NH (MNH); however, its occurrence in the lower leg is extremely rare with only one other case reported to date. In this report, we present a rare case of MNH occurring in the lower leg which was resected with the intent to make a diagnosis. At the final follow-up after 11 months, no local recurrence or metastasis has been observed.

18F-FDG PET/CT Imaging of Hidradenocarcinoma Arising From Preexisting Hidradenoma of the Knee

Malignant tumors of the sweat glands are exceedingly rare and aggressive tumors. We present here a case of a 60-year-old man with a malignant hidradenocarcinoma that developed in a background of preexisting benign hidradenoma on the lateral aspect of the knee that was initially resected, but rapidly recurred with associated inguinal lymphadenopathy. F-FDG PET/CT was performed as part of preoperative staging, which demonstrated abnormal inguinal lymph nodes and metastatic disease to the lungs. FDG PET/CT can play an invaluable role in the initial staging and follow-up of this rare malignancy.

Mohs micrographic surgery for the treatment of hidradenocarcinoma: the Mayo Clinic experience from 1993 to 2013

BACKGROUND

Hidradenocarcinoma (HAC) is a rare malignant adnexal neoplasm with reported metastatic potential and undefined optimal treatment.

OBJECTIVE

To review clinical characteristics and outcomes of patients with HAC treated with Mohs micrographic surgery (MMS).

MATERIALS AND METHODS

The authors performed a retrospective chart review of patients with HAC treated by MMS at Mayo Clinic from 1993 to 2013, recording patient demographics, tumor characteristics, MMS stages to clearance, follow-up, recurrence, metastasis, and mortality.

RESULTS

Ten patients underwent MMS for HAC more than 20 years. The average age was 62.8 years, with 6 females and 4 males. Occipital scalp was the most common location (40%), followed by extremities (30%) and face (20%). In 5 of 7 cases (71%), "cyst" was the working clinical diagnosis. The average preoperative lesion area was 3.18 cm, with an average of 1.5 MMS stages required for clearance. Mean postoperative follow-up was 7 years (range, 5-205 months). No tumors treated with MMS recurred, metastasized, or led to disease-related mortality.

CONCLUSION

Mohs micrographic surgery seems to be a useful treatment modality for HAC. This is the largest reported series of HAC treated with MMS with long-term follow-up.