18 F-FDG PET/CT imaging of small intestinal metastasis from pulmonary sarcomatoid carcinoma: Brief report and review of the literature

18F-FDG PET/CT imaging in pulmonary sarcomatoid carcinoma

Background

Pulmonary sarcomatoid carcinoma (PSC) is a rare highly aggressive and poorly differentiated non-small cell carcinoma, and little is known about the information on the usefulness of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). We investigated the clinical and 18F-FDG PET/CT features of PSC.

Methods

We retrospectively analyzed 25 consecutive PSC patients who had undergone 18F-FDG PET/CT. Demographic data, PET/CT findings before treatment, pathological features, and prognosis in these patients were investigated to define correlates between maximal standard uptake value (SUVmax) and clinicopathological parameters.

Results

From March 2017 to January 2023, twenty-five eligible patients with PSC were identified. There were 23 (92%) men, aged 68.5 ± 8.5 (range 56-90) years. Eighteen (72%) patients had a frequent smoking history. The mean size of PSCs was 59.3 ± 18.6 (range 29-97) mm, and 23 (92%) PSCs were Stage IV tumors. 20 (80%) lesions were located in the upper lung and 19 (76%) cases belonged to the peripheral type. Necrotic foci appeared in 21(84%) tumors. 11 (44%) PSCs invaded the pleura. All PSCs were FDG avid, and the mean of SUVmax was 11.8 ± 5.3 (range 4.8-25.5). Metastases were found on PET/CT in 24(96%) patients. The SUVmax of the lesions ≥ 5cm was higher than that of the lesions < 5cm (p=0.004), and the SUVmax of lesions with TTF-1 expression was higher than those of lesions without TTF-1 expression (p=0.009). All of the 25 primary lesions were considered malignant and confirmative, probable, and possible diagnosis of PSC was made in 2 (8%), 4 (16%), and 5(20%) patients, respectively on PET/CT. PSC was not considered in 14 (56%) patients, in PET/CT. The survival of patients with surgery didn't demonstrate a significantly good prognosis as compared with those without surgery (p=0.675).

Conclusion

All PSCs had obvious FDG avidity. Although imaging diagnosis is still difficult, combined clinical and imaging features more than 40% of primary lesions were considered for the possibility of PSC in our group. Early histopathological diagnosis is necessary to help develop a reasonable regimen.

Successful resection of colonic metastasis of lung cancer after colonic stent placement: A case report and review of the literature

BACKGROUND

Lung cancer is the leading cause of cancer deaths worldwide. Although lung cancer can metastasize to various organs such as the liver, lymph nodes, adrenal gland, bone, and brain, metastases to the digestive organs, especially the colon, are rare.

CASE SUMMARY

An 83-year-old man diagnosed with lung cancer received radiation and chemoimmunotherapy, resulting in a complete clinical response. One year after the initial lung cancer diagnosis, the patient presented with obstructive ileus caused by a tumor in the descending colon. An elective left hemicolectomy was successfully performed after the endoscopic placement of a self-expandable metallic stent (SEMS). Pathologically, the tumor of the descending colon was diagnosed as lung cancer metastasis. The postoperative course was uneventful, and the patient is in good condition 13 mo after surgery, with no signs of recurrence. The previous 23 cases of surgical resection of colonic metastasis from lung cancer were reviewed using PubMed to characterize their clinicopathological features and outcomes.

CONCLUSION

SEMS is useful for obstructive colonic metastasis as a bridge to surgery to avoid emergency operations.

Intraluminal Small Bowel Metastasis From Primary Lung Cancer

Lung cancer is the leading cause of cancer-related death worldwide, with frequent metastases to the brain, liver, adrenal glands, and bone. The incidence of intraluminal small bowel metastases of the lung is extremely rare and poorly documented within the literature. Few case studies have been published since the late 1980s and early 1990s. However, little is known about this rare form of metastasis. Small bowel metastatic disease has atypical symptoms that mimic a variety of other diseases; as a result, signs and symptoms may be overlooked until the disease has progressed to a late stage. Signs of small bowel obstruction, symptomatic anemia, abdominal pain, and peritonitis are commonly reported signs and symptoms. Various modalities can be utilized for the workup of suspected small bowel metastasis, including positron emission tomography, computed tomography, and various forms of endoscopy. The prognosis for lung cancer patients with intestinal metastases is poor, with many only surviving months to a few years after diagnosis. Therefore, it is critical to consider small bowel masses as a differential diagnosis in a patient with primary lung cancer who demonstrates clinical signs consistent with symptomatic anemia secondary to gastrointestinal (GI) bleeding, peritonitis, or small bowel obstruction. We report an unusual case of intraluminal and fungating small bowel masses in a patient who had previously undergone lung resections and chemo-immunotherapy. She was diagnosed with non-small undifferentiated carcinoma with tumor necrosis over 12 years before disease recurrence in the bilateral lungs, right adrenal gland, bone, and small bowel. The discovery of the small bowel metastases occurred while undergoing treatment for advanced-stage disease. At this time, she completed chemo-immunotherapy and remained on maintenance immunotherapy. The patient also underwent a partial right adrenalectomy and radiotherapy to the right adrenal gland. Given that she was experiencing symptomatic anemia and further workup indicated that the GI masses were causing her anemia, she underwent palliative small bowel resection of the masses. The pathology results demonstrated that the masses originated from her primary lung cancer, confirming metastatic disease to the small bowel.

Pulmonary Sarcomatoid Carcinoma With Epiglottis and Ileum Metastasis Detected by 18F-FDG PET/CT

ABSTRACT

Pulmonary sarcomatoid carcinoma is a rare subtype of non-small cell lung cancer with poor prognosis. It often metastasizes to lymph nodes, bone, adrenal gland, liver, and brain. Herein, we present a case of a pulmonary sarcomatoid carcinoma patient with epiglottis and ileum metastasis detected by 18F-FDG PET/CT. Lymphoma or multiple primary cancers with or without regional node metastasis were suspected. Ultimately, histopathology after biopsy revealed pulmonary sarcomatoid carcinoma with epiglottic and ileum metastases. Our case highlights the unique advantages of 18F-FDG PET/CT in searching for the unsuspected metastasis.

Prognostic value of PET parameters in patients with pleomorphic lung cancer: Results from a single institution

OBJECTIVES

Pleomorphic lung carcinoma (PLC) is a rare histotype of non-small cell lung cancer (NSCLC) characterized by aggressive clinical course, poor response to therapy and poor prognosis. Therefore, aim of our study is to analyze with 18F-FDG PET/CT a subset of patients affected by PLC to evaluate their metabolic characteristics in terms of SUVmax, MTV and TLG, in order to correlate them with overall survival (OS) and disease-free survival (DFS).

MATERIAL AND METHODS

We retrospectively analyzed 49 consecutive patients with histologically defined PLC occurred to our Institution between 2003 and 2014. All patients underwent F18-FDG PET-CT before surgery and primary tumor was automatically segmented using an isocontour threshold method. SUV threshold for tumor segmentation was defined as the 41 % of lesion SUVmax. Total volume of the segmented VOI (MTV, centimeters cubed) and average SUV (SUVavg, grams per milliliter) in the segmented VOI were measured.

RESULTS

In our population men were significantly more affected than women (42:7). According to Youden criteria, SUVmax, MTV41 and TLG41 best cut-off values to predict 2-year mortality were, 18.95, 27.89 and 290.45, respectively, with TLG41 showing best specificity (85 %) and positive predictive value (82.4 %). As concerning 2-year recurrence, SUVmax, MTV41 and TLG41 best cut-off values were 10.08, 27.89 and 134.85, with SUVmax showing best sensitivity (96.7 %) and negative predictive value (85.7 %). ROC curves confirmed that SUVmax, MTV41 and TLG41 were equally accurate to predict 2-year mortality and 2-year recurrence in our population.

CONCLUSION

Metabolic biomarkers such as SUVmax, MTV and TLG can be used as a prognostic index for disease progression, recurrence and death in patients with PLC, independently from other clinical/pathological prognostic elements.