Successful Treatment of a Locally Recurrent and Metastatic Malignant Phyllodes Tumor with Accelerated Radiotherapy and Nab-Paclitaxel, Cisplatin, and Liposomal Doxorubicin Chemotherapy

Precise diagnosis of breast phyllodes tumors using Raman spectroscopy: Biochemical fingerprint, tumor metabolism and possible mechanism

BACKGROUND

Breast fibroadenomas and phyllodes tumors are both fibroepithelial tumors with comparable histological characteristics. However, rapid and precise differential diagnosis is a tough point in clinical pathology. Given the tendency of phyllodes tumors to recur, the difficulty in differential diagnosis with fibroadenomas leads to the difficulty in optimal management for these patients.

METHOD

In this study, we used Raman spectroscopy to differentiate phyllodes tumors from breast fibroadenomas based on the biochemical and metabolic composition and develop a classification model. The model was validated by 5-fold cross-validation in the training set and tested in an independent test set. The potential metabolic differences between the two types of tumors observed in Raman spectroscopy were confirmed by targeted metabolomic analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

A total of 204 patients with formalin-fixed paraffin-embedded (FFPE) tissue samples, including 100 fibroadenomas and 104 phyllodes tumors were recruited from April 2014 to August 2021. All patients were randomly divided into the training cohort (n = 153) and the test cohort (n = 51). The Raman classification model could differentiate phyllodes tumor versus fibroadenoma with cross-validation accuracy, sensitivity, precision, and area under curve (AUC) of 85.58 % ± 1.77 %, 83.82 % ± 1.01 %, 87.65 % ± 4.22 %, and 93.18 % ± 1.98 %, respectively. When tested in the independent test set, it performed well with the test accuracy, sensitivity, specificity, and AUC of 83.50 %, 86.54 %, 80.39 %, and 90.71 %. Furthermore, the AUC was significantly higher for the Raman model than that for ultrasound (P = 0.0017) and frozen section diagnosis (P < 0.0001). When it came to much more difficult diagnosis between fibroadenoma and benign or small-size phyllodes tumor for pathological examination, the Raman model was capable of differentiating with AUC up to 97.45 % and 95.61 %, respectively. On the other hand, targeted metabolomic analysis, based on fresh-frozen tissue samples, confirmed the differential metabolites (including thymine, dihydrothymine, trans-4-hydroxy-l-proline, etc.) identified from Raman spectra between phyllodes tumor and fibroadenoma.

SIGNIFICANCE AND NOVELTY

In this study, we obtained the molecular information map of breast phyllodes tumors provided by Raman spectroscopy for the first time. We identified a novel Raman fingerprint signature with the potential to precisely characterize and distinguish phyllodes tumors from fibroadenoma as a quick and accurate diagnostic tool. Raman spectroscopy is expected to further guide the precise diagnosis and optimal treatment of breast fibroepithelial tumors in the future.

Metastatic and Malignant Phyllodes Tumors of the Breast: An Update for Current Management

Metastatic, malignant phyllodes tumor (PT) of the breast is a rare and aggressive neoplasm. Currently, there is no agreed upon consensus as to best management practices. A systematic review of literature was conducted investigating surgical, chemotherapeutic, and radiotherapeutic management for metastatic PT. Databases employed to identify articles included Embase, PubMed, and SAGE Journals. Diagnosis of metastatic PT has been of significant difficulty to radiologists as it is often confused with fibroadenomas. Surgically, metastatectomy has been correlated with increased overall survival (of 25.9 versus 9.9 months; P = .01). Radiotherapy has often been associated with palliation and pain control in metastatic, malignant neoplasia. However, one study showed that in malignant PT, radiation was associated with significantly lower rates of local recurrence (OR: 0.048 versus 0.209). Anthracycline containing chemotherapy regimens has been associated with improved overall survival (22.4 months versus 13.2 months; P = .040). Further research must be conducted into this rare malignancy to elucidate accurate diagnosis and care for patients with advanced metastatic or malignant phyllodes tumors.

Case Report: A 13-year-old adolescent diagnosed as malignant phyllodes tumor combined with rhabdomyosarcoma differentiation

Phyllodes tumor (PT) is an infrequent type of breast neoplasm, constituting a mere 0.5%-1.5% of the entirety of breast tumors. The malignant phyllodes tumor (MPT) comprises only 15% of all phyllodes tumors, and its transformation into rhabdomyosarcoma (RMS) is exceedingly rare in clinical practice. Given its insensitivity to chemotherapy and radiotherapy, treatment options for MPT patients are limited, leaving complete surgical resection as the only option. Therefore, it is imperative to investigate the effective utilization of the heterogeneous differentiation characteristics of MPT to expand treatment alternatives for these patients. In this case report, we represent a 13-year-old adolescent diagnosed with giant breast MPT with RMS differentiation and pulmonary metastasis. The initial step in the treatment process involved radical surgical resection, followed by the administration of four cycles of VDC/IC chemotherapy, which is widely recognized as the standard chemotherapy for RMS. Regrettably, the delay in initiating chemotherapy resulted in minimal observable changes in the size of the pulmonary metastatic nodule. Additionally, a comprehensive literature review on the characterization of MPT with heterogeneous differentiation was conducted to enhance comprehension of the diagnosis and treatment of this uncommon disease in clinical practice. Meanwhile, this case also reminds the doctors that when we diagnose a patient as MPT, it is crucial to consider its heterogenous nature and promptly initiate adjuvant treatment. By targeting the differentiation element of MPT, it becomes feasible to overcome the previously perceived limitation of surgical intervention as the sole treatment option.

New Staging System and Prognostic Model for Malignant Phyllodes Tumor Patients without Distant Metastasis: A Development and Validation Study

PURPOSE

To build a new staging system and new prognostic models for MPTB.

METHODS

We performed a comprehensive analysis of the data from the SEER database.

RESULTS

We discussed the characteristics of MPTB by comparing 1085 MPTB cases with 382,718 invasive ductal carcinoma cases. We established a new stage- and age-stratification system for MPTB patients. Furthermore, we built two prognostic models for MPTB patients. The validity of these models was confirmed through multifaceted and multidata verification.

CONCLUSIONS

Our study provided a staging system and prognostic models for MPTB patients, which can not only help to predict patient outcomes, but also enhance the understanding of the prognostic factors associated with MPTB.

Malignant phyllodes tumor of the breast with metastases to the lungs: A case report and literature review

Phyllodes tumors (PTs) are rare fibroepithelial neoplasms of the breasts. Approximately 10%-15% of PTs are malignant, and 9%-27% of patients with malignant PTs, develop metastatic disease. The lungs are the most common target organ for distant metastasis of PT. We report a case of 44-year-old female with a malignant PT. It had recurred locally 3 times, and 3 relapses occurred 13 months after the first diagnosis, presenting multiple metastases to the lungs by CT scan. The patient underwent radiation therapy, and palliative chemotherapy with doxorubicin was initiated. Two courses of doxorubicin therapy were administered, but the patient expired 16 months after PT diagnosis. We present a rare case of malignant PT with local recurrences, lung metastases, and poor patient outcome. Although malignant breast PTs have an unfavorable prognosis, adjuvant radiotherapy combined with margin-negative resection may be associated with decreased local recurrence and distant metastasis rates. Future research should include randomized clinical trials or well-designed prospective matched studies to clarify the effectiveness of treatments of PTs.

A case of malignant phyllodes tumor that responded to pazopanib and developed pneumothorax

Here, we present a 59-year-old female with recurrent malignant phyllodes tumor with multiple lung and lymph node metastases who developed a pneumothorax after the administration of pazopanib. The patient received pazopanib as the second-line chemotherapy. After 2.5 months of the therapy, computed tomography (CT) showed a decrease in the sizes and cavitation of lung lesions; however, a left pneumothorax was newly observed. It was difficult to distinguish the pneumothorax by upright chest X-ray. Typical symptom or physical finding of pneumothorax, such as dyspnea, chest pain or decreased breath sound was not observed. As the pneumothorax was small and asymptomatic, the administration of pazopanib was discontinued and follow-up chest X-ray and CT were performed. After 1 week, CT showed an improvement in the pneumothorax. Chemotherapy was switched to eribulin; however, a rapid increase in sizes of lung lesions was observed after the first administration of eribulin, pazopanib was reintroduced. Careful follow-up by chest X-ray and CT was performed and the pneumothorax has not recurred.

Malignant Phyllodes Tumor of the Breast: Case Report

Introduction: Phyllodes tumors (PT) are rare and account for 0.3% to 0.5% of all breast tumors. PT may be classified as benign, borderline or malignant. The aim of this study was to report a case of malignant PT of the breast. Case report: A 27-year-old woman presented with a mass in the left breast with histopathological features of malignancy (results of US of the breast: an oval, lobulated hypoechogenic lesion, measuring 7.7 cm – BI-RADS® 4C). A segmental resection (SR) of the breast was performed and histopathology study of the surgical specimen confirmed a malignant PT. Adjuvant radiotherapy was used for supplemental treatment. One year later, the patient had a local recurrence of the primary tumor and underwent a new SR of the left breast. There was no indication of breast reirradiation. At about 31 months after diagnosis (September 2019 – April 2022), the patient is well and adherent to periodical clinical follow-up. Conclusion: This study presents a case of malignant PT that occurred in a young patient and had a more aggressive course.