Low-Malignant Schwannoma of the Cervix in Pregnancy: A Case Report and Literature Systematic Review

Primary cervical melanocytic schwannomas, arising from the sympathetic chain, are very rare pigmented neural sheath tumors that, both grossly and clinically, are often misdiagnosed with other more frequent lesions of the uterine cervix. Literature review accounts for seventeen published cases of schwannomas of the cervix, ten of which are malignant and seven benign. Pathological examination with immunostaining techniques is essential for the correct diagnosis of these tumors. We report a case of primary cervical schwannoma in a 32-year-old female who was referred to our department at 13 weeks of gestation with a diagnosis of malignant melanoma of the cervix. Pathological review detailed a neoplasm with a myxoid spindle cell component and a minority of small epithelioid cells, with a low-malignant potential proliferation index: morphological and immunocytochemical findings were compatible with the diagnosis of nerve sheath tumor, type schwannoma. The patient underwent a vaginal trachelectomy and a prophylactic Shirodkar’s cerclage. Pregnancy was carried on without any negative event. The patient delivered by a caesarean section a healthy female newborn. Placental histology was negative. After 6 years from the first diagnosis, the patient is healthy and disease free.

Incidence of malignancy after pediatric kidney transplantation: a single-center experience over the past three decades in Japan

Background Malignancy after kidney transplantation (KT) is one of the most serious post-transplant complications. This study aimed to investigate the incidence, type, and outcomes of malignancy after pediatric KT. Methods We performed a retrospective cohort study on pediatric kidney transplant recipients aged 18 years or younger who received their first transplant between 1975 and 2009. Results Among the 375 children who underwent KT, 212 were male (56.5%) and 163 were female (43.5%) (median age at KT, 9.6 years [interquartile range {IQR}] 5.8–12.9 years). The incidence of malignancy was 5.6% (n = 21). The cumulative incidences of cancer were 0.8%, 2.5%, 2.8%, 4.2%, 5.5%, and 15.6% at 1, 5, 10, 15, 20, and 30 years post-transplantation, respectively. Of 375 patients, 12 (3.2%) had solid cancer and nine (2.4%) had lymphoproliferative malignancy. The median age at the first malignancy was 21.3 years (IQR 11.5–33.3 years). The median times from transplant to diagnosis were 22.3 years (IQR 12.3–26.6 years) for solid cancer and 2.2 years (IQR 0.6–2.8) for lymphoproliferative malignancies. During follow-up, five recipients died due to malignancy. The causes of death were hepatocellular carcinoma in one patient, squamous cell carcinoma in the transplanted kidney in one patient, malignant schwannoma in one patient, and Epstein-Barr virus-related lymphoma in two patients. The mortality rate was 0.79 per 1000 person-years (95% confidence interval 0.38, 1.85). Conclusions Early diagnosis and treatment of malignancies in transplant recipients is an important challenge. Therefore, enhanced surveillance and continued vigilance for malignancy following KT are necessary.

RECURRENCE OF MALIGNANT PERIPHERAL NERVE SHEATH TUMOR

Peripheral nerve sheath tumor (PNST) is known as a benign tumor called Schwannomas, developed from the Schwann cells that produce myelin and collagen, and can occur in a wide variety of locations. In some cases, it can take a malignant turn and grow as a pelvic mass known as malignant peripheral nerve sheath tumor (MPNST), malignant schwannoma, malignant neurofibroma, malignant mesenchynoma and neurogenic sarcoma. Our case report presents a female patient presenting dysuria and pelvic pain. The clinical examination revealed a palpable mass in the lower abdomen. The computer tomography (CT) scan of the abdomen and pelvic region showed a tumor mass that was in contact with the nearby organs, but not infiltrating them. After the surgery, histopathology confirmed the MPNST proliferation. A month after, the patient returned for a follow-up and presenting pelvic pain. The CT scan of the abdomen and pelvic region showed a tumoral mass compressing the nearby organs, but not infiltrating them. The patient was referred to oncology board for palliative treatment. The particularity of this case report is the short period of time recurrence of the MPNST, rather than metastases. The most important treatment for MPNSTs remains surgery, trying to achieve negative margins. However, there have been reported two cases of unresectable MPSNT with partial remission to chemo- and radiotherapy.

Retrospective analysis of intraoperative radiation therapy with low-kilovoltage x-rays (IORT-LK) in soft tissue sarcomas (STS).

e23575 Background: STS include a heterogeneous group of malignancies that arises from or into connective tissues and limbs are the preferential primary sites. An adequate local control with multimodality therapy can be obtained in most cases. An additional approach, that is, the IORT-LK is able to deliver high dose to risky areas for recurrence, minimizing the toxicity to structures around the target. Such an importance is even greater in abdominal sarcomas, because there is some difficulty in removing the whole neoplasia with clear margins. IORT-LK has the advantage of higher Relative Biological Effectiveness (RBE), a mathematical model that measures the potential for tumour double-strand break (radiation effectiveness), that is close to Proton beam and higher than electron beam. Nevertheless, IORT-LK is not free of complications. It has been reported peripheral neuropathy and enteritis, in cases of limb and abdominal STS, respectively. Methods: In this retrospective study from a single Brazilian institution (Hospital Alemão Oswaldo Cruz), we reported 6 patients with histologically confirmed STS, that underwent IORT-LK (Intrabeam - Carl Zeiss). There are 3 male and 3 female patients, with a median age 48 years, and mean of 39 years. The histological subtypes are as follows: fibromyxoid sarcoma, high grade pleomorphic sarcoma, desmoid tumor, chondrosarcoma, dedifferentiated liposarcoma and malignant schwannoma - one subtype for each patient. The primary sites are: inferior limb (3), superior limb (1) and abdomen (2). Results: IORT-LK was administered in doses that ranged from 14 to 15 Gy to the involved area. Two patients, each one with a limb STS, received also neoadjuvant chemotherapy. With a mean follow-up of 30 months, there is no local recurrence among the 6 patients reported. The first patient received the IORT-LK in April, 2017 and the last one in July, 2019. All of them had clinical observation up-to-dated on January, 2020. No serious complications were observed, but one patient had a moderate local infection. Conclusions: The therapy was well tolerated. We must emphasize that dose previously used by Brussiers was slightly superior than ours but with electrons and not Low-Kylovoltage. In his pilot study it was used 17 Gy for treatment of abdominal sarcomas. In sum, we believe that IORT-LK has higher RBE than previous available equipment and can improve local control of STS, mainly those that arise on the extremities. Future studies must be carried out to confirm our initial impression.

Malignant trigeminal nerve Schwannoma diagnosed via biopsy of the infraorbital nerve in a dog

A 12-year old, female neutered English Pointer presented with right-sided temporalis muscle atrophy and facial irritation over 2 weeks. Neurolocalisation was consistent with a right trigeminal neuropathy. MRI revealed a severely enlarged trigeminal nerve with involvement of the infraorbital nerve, which was palpable as a firm swelling over the maxilla. Incisional biopsy of the infraorbital nerve was performed and histopathological diagnosis was a malignant Schwannoma. Palliative chemotherapy was initiated. Two months following diagnosis the owner reported that the dog was doing well. This is the first report of a trigeminal nerve sheath tumour diagnosed via biopsy of the infraorbital nerve in a dog. Consideration should be given to evaluating the infraorbital nerve on clinical examination as well as MRI in cases of trigeminal neuropathy.

Malignant tumor of the peripheral nerve sheaths in the parotid gland - a case report

Neoplasms of the parotid glands constitute about 6% of head and neck tumours, the most common of which are: adenoma multiforme and Warthin’s tumor. Schwannoma is benign, encapsulated tumor of the nerve cells (lemocytes, Schwann cells), most often it occurs in the trunk, head, extremely rarely observed in the parotid gland. 9% Schwannomas derives from the facial nerve sheath, constituting from 0.5% -1.2% of all salivary gland tumors. The literature describes 80 cases of intraparotid Schwannoma. Malignant Schwannoma (MPNST) account for 5% to 10% of all soft tissue sarcomas. High-grade MPNST tumors are aggressive, with a tendency to relapse and metastasis. We present a case report of a 84-year-old female patient presented to the Head and Neck Oncology Clinic of the Medical University of Lodz, due to the painful tumor of the left parotid region. The tumor appeared six months before hospitalization. During the physical examination, there was a polycyclic tumor with reduced mobility, the skin on the tumor was slightly red, lymph nodes uninvolved, facial nerve function preserved. BACC revealed tumour tissue composed of sheets and spindle-shaped cells. The patient was qualified for surgical treatment. Under the general anesthesia the superficial lobe of the parotid gland along with the tumor was removed. After the procedure, no facial nerve palsy was found. The patient did well post-operatively and was discharged home on the 8th day after surgery. Immunohistochemical staining showed the tumour cells to be diffusely and strongly immunoreactive for S-100 protein and Ki67 40-50%. Strong and diffuse staining for S-100 protein were consistent with the malignant peripheral nerve sheath tumour (MPNST). The patient was referred for radiotherapy, due to the postoperative outcome and advanced age, no adjuvant treatment was proposed. The patient has been in observation for 1 year. No relapse was found in the follow-up studies.